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Home My WebLink AboutDrainage Report DRAINAGE REPORT FOR INDIAN LAKES SUBDIVISION PHASE 19 March 2015 PREPARED FOR: SMILING MALLARD DEVELOPMENT, LTD. 3608 EAST 29TH STREET BRYAN, TEXAS 77802 979-846-4384 MBESI No. 10620046 I • __1\ 81 ID° McCLURE & BROWNE ENGINEERING/SURVEYING, INC. 1008 Woodcreek Dr.,Suite 103• College Station,Tx.77845• (979)693-3838 Engineer Reg.No.F-458 Survey Reg.No. 101033-00 4 1 1 1 i i 1 1 1 i 1 1 1 1 1 1 Indian Lakes Subdivision, Phase 19 Stormwater Management Technical Design Summary Report MBESI No. 10620046 PART 1 —Executive Summary Report Section 1 —Contact Information Project Designer: McClure and Browne Engineering and Surveying, Inc. 1008 Woodcreek Drive, Suite 103 College Station, TX 77845 979-693-3838 Project Developer: Smiling Mallard Development, Ltd. 3608 East 29th Street Bryan, Texas 77802 Section 2—General Information and Project Location This development is the 19th phase of a multi-phase subdivision. Phase 19 consists of 16 lots. The phase is located in the Indian Lakes Village which is down Arrington Rd. approximately 2 miles from the Arrington Rd. William D. Fitch Pkwy intersection. Phase 19 lies in the northeast portion of the subdivision near the intersection of Mesa Verde Drive and Kachina Cove. The entire subdivision has been analyzed in the initial drainage report submitted in September, 2000. The development is located within the ETJ of College Station. w The project site is in the Peach Creek watershed. According to the Flood Insurance Rate Maps for Brazos County, Texas and incorporated area, Map Number 48041C0350E effective May 16, 2012; no portion of this property is located in a 100-year flood hazard area. Culvert pipe and ditch sizing calculations are shown with this submittal. A small portion of this phase drains to the north into a tributary in the Deer Park Subdivision. This area is identified as Drainage Area#1 on Exhibit B. -There is no planned detention of this drainage since it is small in nature and discharges directly into an existing creek channel. The existing and proposed conditions are as follows: tau itArto Drainage Report Indian Lakes, Phase 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Drainage Area 1 Analysis Storm Event Post Development Flow Pre Development Flow Difference 2-year 6.7 cfs 5.4 cfs 1.30 cfs 5-year 8.19 cfs 6.55 cfs 1.64 cfs 10-year 9.20 cfs 7.36 cfs 1.84 cfs 25-year 10.50 cfs 8.40 cfs 2.10 cfs 50-year 11.87 cfs 9.50 cfs 2.37 cfs 100-year 12.15 cfs 9.72 cfs 2.43 cfs The culverts and ditches peak runoffs were found using the Rational Method. A runoff coefficient (c) of 0.50 was used for residential areas since all the lots have an area greater than 1 acre. The ditches along the proposed roadways are uniform throughout the project. The ditch profiles along all proposed roadways were determined using the largest ditch drainage area found for Phase 19. The culverts and ditches were analyzed using an Excel Spreadsheet which utilizes Manning's Equation for the analysis. ESection 3 —Reference Exhibit A Technical Design Summary Exhibit B Drainage Area Map Exhibit C-1 Rational Method Calculations Exhibit C-2 Culvert Sizing Calculations Exhibit C-3 Ditch Capacity Calculations C Drainage Report Indian Lakes, Phase 19 1 i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 , I E , II 1 B . I , E EXHIBIT S - 1 , 1 , E ,' E .,, Drainage Report Indian Lakes, Phase 19 r 1 1 1 1 1 1 1 i 1 1 1 1 1 1 1 1 EXHIBIT A Technical Design Summary Drainage Report Indian Lakes, Phase 19 t 11 t 1 SECTION IX _ APPENDIX D - TECHNICAL DESIGN SUMMARY The Cities of Bryan and College Station both require storm drainage design to follow these Unified Stormwater Design Guidelines. Paragraph C2 of Section III (Administration) requires submittal of a drainage report in support of the drainage plan (stormwater management plan) proposed in connection with land development projects, both site projects and subdivisions. That report may be submitted as a traditional prose report, complete with applicable maps, graphs, tables and drawings, or it may take the form of a "Technical Design Summary". The format and content for such a summary report shall be in substantial conformance with the description in this Appendix to those Guidelines. In either format the report must answer the questions (affirmative or negative) and provide, at minimum, the information prescribed in the "Technical Design Summary" in this Appendix. The Stormwater Management Technical Design Summary Report shall include several parts as listed below. The information called for in each part must be provided as applicable. In addition to the requirements for the Executive Summary, this Appendix includes several pages detailing the requirements for a Technical Design Summary Report as forms to be completed. These are provided so that they may be copied and completed or scanned and digitized. In addition, electronic versions of the report forms may be obtained from the City. Requirements for the means (medium) of submittal are the same as for a conventional report as detailed in Section HI of these Guidelines. Note: Part 1 — Executive Summary must accompany any drainage report required to be provided in connection with any land development project, regardless of the format chosen for said report. Note: Parts 2 through 6 are to be provided via the forms provided in this Appendix. Brief statements should be included in the forms as requested, but additional information should be attached as necessary. Part 1 — Executive Summary Report Part 2— Project Administration Part 3— Project Characteristics Part 4— Drainage Concept and Design Parameters Part 5— Plans and Specifications Part 6— Conclusions and Attestation STORMWATER MANAGEMENT TECHNICAL DESIGN SUMMARY REPORT Part 1 — Executive Summary This is to be a brief prose report that must address each of the seven areas listed below. Ideally it will include one or more paragraphs about each item. 1. Name, address, and contact information of the engineer submitting the report, and of the land owner and developer (or applicant if not the owner or developer). The date of submittal should also be included. 2. Identification of the size and general nature of the proposed project, including any proposed project phases. This paragraph should also include reference to applications that are in process with either City: plat(s), site plans, zoning requests, STORMWATER DESIGN GUIDELINES Page 1 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY or clearing/grading permits, as well as reference to any application numbers or codes assigned by the City to such request. , 3. The location of the project should be described. This should identify the Named Regulatory Watershed(s) in which it is located, how the entire g ry project area is situated therein, whether the property straddles a watershed or basin divide, the approximate acreage in each basin, and whether its position in the Watershed dictates use of detention design. The approximate proportion of the property in the IPP city limits and within the ETJ is to be identified, including whether the property straddles city jurisdictional lines. If any portion of the property is in floodplains as described in Flood Insurance Rate Maps published by FEMA that should be disclosed. 41104 4. The hydrologic characteristics of the property are to be described in broad terms: existing land cover; how and where stormwater drains to and from neighboring properties; ponds or wetland areas that tend to detain or store stormwater; existing creeks, channels, and swales crossing or serving the property; all existing drainage easements (or ROW) on the property, or on neighboring properties if they service runoff to or from the property. 5. The general plan for managing stormwater in the entire project area must be outlined to include the approximate size, and extent of use, of any of the following features: storm drains coupled with streets; detention / retention facilities; buried conveyance conduit independent of streets; swales or channels; bridges or culverts; outfalls to principal watercourses or their tributaries; and treatment(s) of existing watercourses. Also, any plans for reclaiming land within floodplain areas must be a� outlined. 6. Coordination and permitting of stormwater matters must be addressed. This is to include any specialized coordination that has occurred or is planned with other entities (local, state, or federal). This may include agencies such as Brazos County government, the Brazos River Authority, the Texas A&M University System, the Texas Department of Transportation, the Texas Commission for Environmental fib Quality, the US Army Corps of Engineers, the US Environmental Protection Agency, et al. Mention must be made of any permits, agreements, or understandings that pertain to the project. 7. Reference is to be made to the full drainage report (or the Technical Design Summary Report) which the executive summary represents. The principal elements of the main report (and its length), including any maps, drawings or construction documents, should be itemized. An example statement might be: ow "One -page drainage report dated , one set of construction drawings ( sheets) dated , and a -page specifications document dated comprise the drainage report for this project." r. 0 0 .r STORMWATER DESIGN GUIDELINES Page 2 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 0 SECTION IX _ APPENDIX D - TECHNICAL DESIGN SUMMARY Part 2 — Project Administration Start (Page 2.1) Engineering and Design Professionals Information Engineering Firm Name and Address: Jurisdiction City: Bryan McClure & Browne Engineering/Surveying, Inc. 1008 Woodcreek Drive, Suite 103 X College Station --- College Station, Texas 77845 Date of Submittal: (979)693-3838 Lead Engineer's Name and Contact Info.(phone, e-mail, fax): Other: Jeffery L. Robertson, P.E. Supporting Engineering/Consulting Firm(s): Other contacts: Developer/ Owner/Applicant Information Developer/Applicant Name and Address: Phone and e-mail: Smiling Mallard Development, Ltd. (979) 846-4384 -. 3608 East 29th Street Bryan, Texas 77802 Property Owner(s) if not Developer/ Applicant(& address): Phone and e-mail: Project Identification Development Name: Indian Lakes, Phase 19 Is subject property a site project, a single-phase subdivision, or part of a multi-phase subdivision? Multi-phase Subdivision If multi-phase, subject property is phase 19 of Legal description of subject property (phase) or Project Area: (see Section II, Paragraph B-3a) Indian Lakes, Phase 19 If subject property (phase) is second or later phase of a project, describe general status of all earlier phases. For most recent earlier phase Include submittal and review dates. The project is the 19th phase of a multi phase subdivision. At this time the first phase has vow been built. Phase 1 was submitted in September, 2000 and consisted of 58 lots. The most recent phase submitted was Ph. 25. General Location of Project Area, or subject property (phase): Project site is located near the intersection of Mesa Verde Drive and Sundance Drive in College Station, Texas. In City Limits? Extraterritorial Jurisdiction (acreage): Bryan: acres. Bryan: College Station: 34.48 College Station: acres. Acreage Outside ETJ: STORMWATER DESIGN GUIDELINES Page 3 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 2 — Project Administration Continued (page 2.2) Project Identification (continued) Roadways abutting or within Project Area or Abutting tracts, platted land, or built subject property: developments: Mesa Verde Drive Indian Lakes, Phase 16 & Undeveloped Land O0 Named Regulatory Watercourse(s) &Watershed(s): Tributary Basin(s): Phase 19 is located in the Peach Creek Watershed. The nearest tributary is Peach Creek S. Tributary 7.2 (See FEMA Map 48041C0350E) . .10 Plat Information For Project or Subject Property(or Phase) 110 Preliminary Plat File#: Final Plat File#: Date: Name: Pending Approval Status and Vol/Pg: Pending Approval If two plats, second name: File#: Status: Date: le Zoning Information For Project or Subject Property(or Phase) OP Zoning Type: Existing or Proposed? Case Code: Case Date Status: Zoning Type: Existing or Proposed? Case Code: Case Date Status: MP Stormwater Management Planning For Project or Subject Property(or Phase) Planning Conference(s) & Date(s): Participants: t Preliminary Report Required? Submittal Date Review Date ma Review Comments Addressed? Yes No In Writing? When? MP Compliance With Preliminary Drainage Report. Briefly describe (or attach documentation ma explaining) any deviation(s) from provisions of Preliminary Drainage Report, if any. am ■r 110 .w STORMWATER DESIGN GUIDELINES Page 4 of 26 APPENDIX. D:TECH. DESIGN SUMMARY ea Effective February 2007 As Revised February 2009 AIS SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 2 — Project Administration Continued (page 2.3) Coordination For Project or Subject Property(or Phase) Note: For any Coordination of stormwater matters indicated below, attach documentation describing and substantiating any agreements, understandings, contracts, or approvals. Coordination Dept. Contact: Date: Subject: With Other Departments of Jurisdiction City(Bryan or College Station) Coordination With Summarize need(s) &actions taken (include contacts&dates): Non-jurisdiction City Needed? Yes No X . . Coordination with Summarize need(s) & actions taken (include contacts &dates): Brazos County Needed? Yes No X Coordination with Summarize need(s) &actions taken (include contacts &dates): 005. TxDOT Needed? 00- Yes No Coordination with Summarize need(s) & actions taken (include contacts &dates): TAMUS Needed? Yes No X Permits For Project or Subject Property (or Phase) 000 As to stormwater management, are permits required for the proposed work from any of the entities listed below? If so, summarize status of efforts toward that objective in spaces below.04. _ Entity Permitted or Status of Actions (include dates) a Approved . _ US Army Crops of Engineers No X Yes US Environmental Protection Agency No X Yes Texas Commission on A Stormwater Pollution Prevention Plan must be Environmental Quality implemented prior to the start of construction No Yes x according to TPDES General Permit No. TXR150000. Brazos River Authority No X Yes STORMWATER DESIGN GUIDELINES Page 5 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY 140 Part 3 - Property Characteristics Start (Page 3.1) ma Nature and Scope of Proposed Work Existing: Land proposed for development currently used, including extent of impervious cover? 40 Existing undeveloped land (Dense tree cover) . Existing impervious cover is wd, approximately 0 sf. Redevelopment of one platted lot, or two or more adjoining platted lots. Site Development Building on a single platted lot of undeveloped land. Project Building on two or more platted adjoining lots of undeveloped land. 40 (select all Building on a single lot, or adjoining lots, where proposed plat will not form applicable) a new street(but may include ROW dedication to existing streets). Other(explain): Subdivision X Construction of streets and utilities to serve one or more platted lots. Development Construction of streets and utilities to serve one or more proposed lots on 40 Project lands represented by pending plats. Site projects: building use(s), approximate floor space, impervious cover ratio. Describe Subdivisions: number of lots by general type of use, linear feet of streets and ow Nature and drainage easements or ROW. Size of This phase of the subdivision includes 16 lots. The development Proposed consists of approximately 3,177 LF of streets with 16' POE on each Project side of the streets ROW. 110 ow Is any work planned on land that is not platted If yes, explain: or on land for which platting is not pending? X No Yes FEMA Floodplains 0 Is any part of subject property abutting a Named Regulatory WatercourseNo x Yes w (Section II, Paragraph B1) or a tributary thereof? Is any part of subject property in floodplainNo Yes X Rate Map 4s041c0350E A area of a FEMA-regulated watercourse? me Encroachment(s) into Floodplain Encroachment purpose(s): Building site(s) Road crossing(s) areas planned? Utility crossing(s) Other(explain): No X ww Yes Mt If floodplain areas not shown on Rate Maps, has work been done toward amending the FEMA- approved Flood Study to define allowable encroachments in proposed areas? Explain. a 40 a STORMWATER DESIGN GUIDELINES Page 6 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 a Mit SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 3 — Property Characteristics Continued (Page 3.2) ow Hydrologic Attributes of Subject Property (or Phase) Has an earlier hydrologic analysis been done for larger area including subject property? Yes Reference the study(&date) here, and attach copy if not already in City files. Indian Lakes Subdivision; September, 2000 X Is the stormwater management plan for the property in substantial conformance with the earlier study? Yes X No If not, explain how it differs. If subject property is not part of multi-phase project, describe stormwater management No plan for the property in Part 4. ' If property is part of multi-phase project, provide overview of stormwater management plan for Project Area here. In Part 4 describe how plan for subject property will comply therewith. Do existing topographic features on subject property store or detain runoff? X No Yes Describe them (include approximate size, volume, outfall, model, etc). Any known drainage or flooding problems in areas near subject property? X No Yes Identify: Based on location of study property in a watershed, is Type 1 Detention (flood control) needed? (see Table B-1 in Appendix B) Detention is required. X Need must be evaluated. Detention not required. What decision has been reached? By whom? 14 Detention study during Phase 1. If the need for How was determination made? Type 1 Detention must be evaluated: Detention was required and is provided for the entire Indian Lakes Subdivision. However, Phase 19 does not require any additional detention. 11 STORMWATER DESIGN GUIDELINES Page 7 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 3 — Property Characteristics Continued (Page 3.3) Hydrologic Attributes of Subject Property (or Phase) (continued) NO Does subject property straddle a Watershed or Basin divide? x No Yes If yes, describe splits below. In Part 4 describe design concept for handling this. +rr Watershed or Basin Larger acreage Lesser acreage 1111 11 Above-Project Areas(Section II, Paragraph B3-a) Does Project Area (project or phase) receive runoff from upland areas? x No Yes MP Size(s) of area(s) in acres: 1) 2) 3) 4) Flow Characteristics (each instance) (overland sheet, shallow concentrated, recognizable concentrated section(s), small creek (non-regulatory), regulatory Watercourse or tributary); MP Overland flow to proposed ditch lines on Phase 19 streets. leat ea Flow determination: Outline hydrologic methods and assumptions: The Rational Method was used for flow calculations and the post development WO land was treated as large acre residential tracts. Does storm runoff drain from public easements or ROW onto or across subject property? x No Yes If yes, describe facilities in easement or ROW: eat OD Are changes in runoff characteristics subject to change in future? Explain No, upstream land is already developed. Conveyance Pathways (Section II, Paragraph C2) NIP Must runoff from study property drain across lower properties before reaching a Regulatory Watercourse or tributary? No x Yes 40 Describe length and characteristics of each conveyance pathway(s). Include ownership of property(ies). IP O. Runoff from Ph. 19 will leave the phase and be discharged into existing tributaries of Peach Creek. The property is a future phase of the Indian Lakes Subdivision. VI 1111 S STORMWATER DESIGN GUIDELINES Page 8 of 26 APPENDIX. D:TECH. DESIGN SUMMARY ow Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 3 — Property Characteristics Continued (Page 3.4) Hydrologic Attributes of Subject Property(or Phase) (continued) Conveyance Pathways (continued) Do drainage If yes, for what part of length? % Created by? plat, or easements instrument. If instrument(s), describe their provisions. exist for any part of leo pathway(s)? X No Yes tie Where runoff must cross lower properties, describe characteristics of abutting lower property(ies). (Existing watercourses? Easement or Consent aquired?) Pathway Areas Describe any built or improved drainage facilities existing near the property (culverts, bridges, lined channels, buried conduit, swales, detention ponds, etc). Nearby Drainage Do any of these have hydrologic or hydraulic influence on proposed stormwater Facilities design? X No Yes If yes, explain: taw 010 00. STORMWATER DESIGN GUIDELINES Page 9 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 or SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY 440 Part 4— Drainage Concept and Design Parameters Start (Page 4.1) Stormwater Management Concept 414 Discharge(s) From Upland Area(s) If runoff is to be received from upland areas, what design drainage features will be used to accommodate it and insure it is not blocked by future development? Describe for each area, flow section, or discharge point. AIR Discharge(s)To Lower Property(ies) (Section II, Paragraph El) Does project include drainage features (existing or future) proposed to become public via 411 platting? X No Yes Separate Instrument? X No Yes Per Guidelines reference above, how will runoff be discharged to neighboring Establishing Easements (Scenario 1) y(ies)? Pre-development Release (Scenario 2)propertAIR Combination of the two Scenarios rrrr Scenario 1_ If easements are proposed, describe where needed, and provide status of actions on each. (Attached Exhibit# ) AIA Scenario 2: Provide general description of how release(s)will be managed to pre-development conditions (detention, sheet flow, partially concentrated, etc.). (Attached Exhibit# ) A#i 1111 rr so Combination: If combination is proposed, explain how discharge will differ from pre- development conditions at the property line for each area (or point) of release. a 0 If Scenario 2, or Combination are to be used, has proposed design been coordinated with owner(s) of receiving property(ies)? No Yes Explain and provide 1111 documentation. as wrt STORMWATER DESIGN GUIDELINES Page 10 of 26 APPENDIX. D:TECH. DESIGN SUMMARY vr Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.2) Stormwater Management Concept(continued) Within Project Area Of Multi-Phase Project Identify gaining Basins or Watersheds and acres shifting: Will project result in shifting runoff between Basins or between What design and mitigation is used to compensate for increased runoff Watersheds? from gaining basin or watershed? X No Yes How will runoff from Project 1. With facility(ies) involving other development projects. Area be mitigated to pre- 2. Establishing features to serve overall Project Area. development conditions? Select any or all of 1, 2, 3. X On phase (or site) project basis within Project Area. and/or 3, and explain below. 1. Shared facility (type& location of facility; design drainage area served; relationship to size of Project Area): (Attached Exhibit# ) 2. For Overall Project Area (type& location of facilities): (Attached Exhibit# ) 3. By phase (or site) prosect: Describe planned mitigation measures for phases (or sites) in subsequent questions of this Part. Are aquatic echosystems proposed? No Yes In which phase(s) or project(s)? a m � CAre other Best Management Practices for reducing stormwater pollutants proposed? No Yes Summarize type of BMP and extent of use: rn '� o � Z If design of any runoff-handling facilities deviate from provisions of B-CS Technical a X Specifications, check type facility(ies) and explain in later questions. Detention elements Conduit elements Channel features Swales Ditches Inlets Valley gutters Outfalls Culvert features Bridges Other II STORMWATER DESIGN GUIDELINES Page 11 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.3) Stormwater Management Concept(continued) Within Project Area Of Multi-Phase Project(continued) op Will Project Area include bridge(s) or culvert(s)? No X Yes Identify type and general size and In which phase(s). Culvert #1 - 24" RCP Pipe on Chaco Canyon Drive 41* Culvert #2 - 18" RCP Pipe on Halona Court If detention/retention serves (will serve) overall Project Area, describe how it relates to subject phase or site project(physical location, conveyance pathway(s), construction sequence): Olt Within Or Serving Subject Property(Phase, or Site) log If property part of larger Project Area, is design in substantial conformance with earlier analysis and report for larger area? Yes No, then summarize the difference(s): , vat Identify whether each of the types of drainage features listed below are included, extent of use, vas and general characteristics. AIA Typical shape? Surfaces? cam• V-Shape Grass err w Steepest side slopes: Usual front slopes: Usual back slopes: nAAI > 4:1 4:1 4:1 N 0 x Flow line slopes: least o.68% Typical distance from travelway: 11' my a Varies (Attached Exhibit# ) o typicalgreatest 2.93 e �, z erg 2 Are longitudinal culvert ends in compliance with B-CS Standard Specifications? X Yes No, then explain: A� rr At intersections or otherwise, do valley gutters cross arterial or collector streets? No Yes If yes explain: w - L U N ;, Are valley gutters proposed to cross any street away from an intersection? a i z No Yes Explain: (number of locations?) rr► tri -2 m x 000 AAI STORMWATER DESIGN GUIDELINES Page 12 of 26 APPENDIX. D:TECH. DESIGN SUMMARY err Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY IPart 4— Drainage Concept and Design Parameters Continued (Page 4.4) Stormwater Management Concept(continued) IWithin Or Serving Subject Property(Phase, or Site) (continued) Gutter line slopes: Least Usual Greatest I Are inlets recessed on arterial and collector streets? Yes No If"no", identify where and why. I Will inlets capture 10-year design stormflow to prevent flooding of intersections(arterial with arterial or collector)? Yes No If no, explain where and why not. r. a [ a) c - • Will inlet size and placement prevent exceeding allowable water spread for 10-year :? design storm throughout site (or phase)? Yes No If no, explain. .. m w c Sag curves: Are inlets placed at low points? Yes No Are inlets and m . conduit sized to prevent 100-year stormflow from ponding at greater than 24 inches? L g Yes No Explain "no" answers. U) m a) E 1/) 2 Will 100-yr stormflow be contained in combination of ROW and buried conduit on Q whole length of all streets? Yes No If no, describe where and why. [ _ Do designs for curb, gutter, and inlets comply with B-CS Technical Specifications? Yes No If not, describe difference(s) and attach justification. 16 M. Are any 12-inch laterals used? No Yes Identify length(s) and where used. f► Pipe runs between system Typical Longest I • access points (feet): aa)) Are junction boxes used at each bend? Yes No If not, explain where >. and why. .. U) c 0 tom La z a E x111 ip tii Are downstream soffits at or below upstream soffits? Least amount that hydraulic Yes No If not, explain where and why: grade line is below gutter line — (system-wide): er ISTORMWATER DESIGN GUIDELINES Page 13 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 II SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY ON Part 4— Drainage Concept and Design Parameters Continued (Page 4.5) VOW Stormwater Management Concept(continued) en Within Or Serving Subject Property(Phase, or Site) (continued) Wet Describe watercourse(s), or system(s) receiving system discharge(s) below U (include design discharge velocity, and angle between converging flow lines). et 1) Watercourse (or system), velocity, and angle? o a E 2) Watercourse (or system), velocity, and angle? o o c o 0 V) E Za 3)Watercourse (or system), velocity, and angle? in cll 70 © S 2 0 rrr 13 a E m For each outfall above, what measures are taken to prevent erosion or scour of .n (receiving and all facilities at juncture? 1) ■r is ra 2) 3) Are swale(s) situated along property lines between properties? No Yes Number of instances: For each instance answer the following questions. „„, Surface treatments (including low-flow flumes if any): cs• a> m } Flow line slopes (minimum and maximum): 11110 13 0 OPo Z Outfall characteristics for each (velocity, convergent angle, & end treatment). U) aux Ta 3 U Will 100-year design storm runoff be contained within easement(s) or platted drainage rrr ROW in all instances? Yes No If"no" explain: 11110 r�r 10 NO S STORMWATER DESIGN GUIDELINES Page 14 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February, 2007 As Revised February 2009 S SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.6) Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) Ili Are roadside ditches used? No X Yes If so, provide the following: Is 25-year flow contained with 6 inches of freeboard throughout? X Yes No y Are top of banks separated from road shoulders 2 feet or more? X Yes No Are all ditch sections trapezoidal and at least 1.5 feet deep? Yes X No N For any"no" answers provide location(s) and explain: I t All Ditches are V-shaped and at least 2 ' deep o o' I If conduit is beneath a swale, provide the following information (each instance). Instance 1 Describe general location, approximate length: >- Is 100-year design flow contained in conduit/swale combination? Yes No - If "no" explain: a) U 1 o as Space for 100 year storm flow? ROW Z Easement Width .c Swale Surface type, minimum Conduit Type and size, minimum and maximum X To and maximum slopes: slopes, design storm: c Io u -o w m Inlets Describe how conduit is loaded (from streets/storm drains, inlets by type): c a c c co N r U a o Access Describe how maintenance access is provided (to swale, into conduit): 0 IP o 1-4 a)• 0 = c — .E .; Instance 2 Describe general location, approximate length: I E — • N c 70 Is 100-year design flow contained in conduit/swale combination? Yes No 0 o If "no" explain: ay E Space for 100-year storm flow? ROW Easement Width o c O w Swale Surface type, minimum Conduit Type and size, minimum and maximum .r 0 Iand maximum slopes: slopes, design storm: c al o a) 2 Inlets Describe how conduit is loaded (from streets/storm drains, inlets by type): To c P. Q Access Describe how maintenance access is provided (to swale, into conduit): ISTORMWATER DESIGN GUIDELINES Page 15 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 I 01 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.7) Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) OW If"yes" provide the following information for each instance: sez Instance 1 Describe general location, approximate length, surfacing: IIP mil ca o w 410 vi Is-100-year design flow contained in swale? Yes No Is swale wholly C } within drainage ROW? Yes No Explain "no" answers: vr. L a) OM oAccess Describe how maintenance access is provide: o ti 5 z ax 00 0 Instance 2 Describe general location, approximate length, surfacing: a> 7 CO cOR m 2 Is 100-year design flow contained in swale? Yes No Is swale wholly a o within drainage ROW? Yes No Explain "no" answers: TTS O — • a Access Describe how maintenance access is provided: U Q Ins- tance 3,4, etc. If swales are used in more than two instances, attach sheet providing all above information for each instance. "New" channels: Will any area(s) of concentrated flow be channelized (deepened, widened, or straightened) or otherwise altered? No Yes If only slightly OP shaped, see"Swales" in this Part. If creating side banks, provide information below. m .E Will design replicate natural channel? Yes No If"no", for each instance o Q describe section shape& area, flow line slope (min. &max.), surfaces, and 100-year o w design flow, and amount of freeboard: 1� Instance 1: w� c a� } E S m o Instance 2: E o Z m S x Instance 3: co me, U S S STORMWATER DESIGN GUIDELINES Page 16 of 26 APPENDIX. D:TECH. DESIGN SUMMARY �r Effective February 2007 As Revised February 2009 S SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.8) Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) Existing channels (small creeks): Are these used? No Yes If"yes" provide the information below. Will small creeks and their floodplains remain undisturbed? Yes No How many disturbance instances? Identify each planned location: For each location, describe length and general type of proposed improvement (including floodplain changes): For each location, describe section shape &area, flow line slope (min. & max.), 1 L surfaces, and 100-year design flow. a 0 c - c Watercourses (and tributaries): Aside from fringe changes, are Regulatory I ° Watercourses proposed to be altered? No Yes Explain below. c Submit full report describing proposed changes to Regulatory Watercourses. Address E existing and proposed section size and shape, surfaces, alignment, flow line changes, olength affected, and capacity, and provide full documentation of analysis procedures aand data. Is full report submitted? Yes No If"no" explain: E TaI c UAll Proposed Channel Work: For all proposed channel work, provide information requested in next three boxes. I If design is to replicate natural channel, identify location and length here, and describe design in Special Design section of this Part of Report. Will 100-year flow be contained with one foot of freeboard? Yes No If not, identify location and explain: I I Are ROW/easements sized to contain channel and required maintenance space? Yes No If not, identify location(s) and explain: it STORMWATER DESIGN GUIDELINES Page 17 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 I SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.9) Stormwater Management Concept(continued) on Within Or Serving Subject Property(Phase, or Site) (continued) How many facilities for subject property project? For each provide info. below. "i` For each dry-type facilitiy: Facility 1 Facility 2 Acres served & design volume + 10% .16 100-yr volume: free flow& plugged Design discharge (10 yr&25 yr) Spillway crest at 100-yr WSE? yes no yes no tio Berms 6 inches above plugged WSE? yes no yes no at Explain any"no" answers: sot a> OR For each facility what is 25-yr design Q, and design of outlet structure? Facility 1: z Facility 2: x Do outlets and spillways discharge into a public facility in easement or ROW? 410 Facility 1: Yes No Facility 2: Yes No If"no" explain: wok a) O 00 0 L a_ For each, what is velocity of 25-yr design discharge at outlet? & at spillway? +� Facility 1: & Facility 2: Olt & Are energy dissipation measures used? No Yes Describe type and L.L location: c 0 OW a> 0 .gt: For each, is spillway surface treatment other than concrete? Yes or no, and describe: Facility 1: 40 Facility 2: For each, what measures are taken to prevent erosion or scour at receiving facility? Facility 1: U. Facility 2: If berms are used give heights, slopes and surface treatments of sides. RI Facility 1: Facility 2: UI U. UI STORMWATER DESIGN GUIDELINES Page 18 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.10) Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) Do structures comply with B-CS Specifications? Yes or no, and explain if"no": Facility 1; U) a) 2 5 Facility 2: c cam. o c .c. o ai - oFor additional facilities provide all same information on a separate sheet. Are parking areas to be used for detention? No Yes What is maximum depth due to required design storm? Roadside Ditches: Will culverts serve access driveways at roadside ditches? No X Yes If"yes", provide information in next two boxes. Will 25-yr. flow pass without flowing over driveway in all cases? X Yes No Without causing flowing or standing water on public roadway? X Yes No m. Designs &materials comply with B-CS Technical Specifications? X Yes No ,,, Explain any"no" answers: I I oAre culverts parallel to public roadway alignment? Yes X No Explain: U N N } N .Q x Creeks at Private Drives: Do private driveways, drives, or streets cross drainage To ways that serve Above-Project areas or are in public easements/ROW? o X m z No Yes If"yes" provide information below. ' How many instances? Describe location and provide information below. [ •Li) I a) Location 1: 0 ;" Location 2: Q Location 3: For each location enter value for: 1 2 3 Design year passing without toping travelway? Water depth on travelway at 25-year flow? Water depth on travelway at 100-year flow? IFor more instances describe location and same information on separate sheet. STORMWATER DESIGN GUIDELINES Page 19 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 I SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.11) Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) Named Regulatory Watercourses (&Tributaries): Are culverts proposed on these facilities? x No Yes, then provide full report documenting assumptions, criteria, analysis, computer programs, and study findings that support proposed design(s). Is report provided? Yes No If"no", explain: so0 Arterial or Major Collector Streets: Will culverts serve these types of roadways? No x Yes How many instances? 2 For each identify the m location and provide the information below. 00 } a Instance1: 24" RCP at Mesa Verde Drive and Chaco Canyon Drive mm N Instance 2: 18" RCP at Chaco Canyon Drive and Halona Court X 1110 0 Instance 3: o ,r� o .i Yes or No for the 100-year design flow: 1 2 3 Headwater WSE 1 foot below lowest curb top? Yes Yes OR c a Spread of headwater within ROW or easement? Yes Yes .ru Is velocity limited per conditions (Table C-11)? Yes Yes Explain any"no" answer(s): c • g N U O -o o 42 Minor Collector or Local Streets: Will culverts serve these types of streets? mx No Yes How many instances? for each identify the at location and provide the information below: 0- Instance 1: .�,. N c Instance 2: Ma as o Instance 3: a� u) 2 c For each instance enter value, or"yes"/"no"for: 1 2 3 Oft U N N c Design yr. headwater WSE 1 ft. below curb top? a, 100-yr. max. depth at street crown 2 feet or less? �. E Product of velocity(fps) &depth at crown (ft) = ? S — o Is velocity limited per conditions (Table C-11)? 0116 Limit of down stream analysis (feet)? Explain any"no" answers: 40 Www S STORMWATER DESIGN GUIDELINES Page 20 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY IPart 4— Drainage Concept and Design Parameters Continued (Page 4.12) Stormwater Management Concept(continued) IWithin Or Serving Subject Property(Phase, or Site) (continued) All Proposed Culverts: For all proposed culvert facilities (except driveway/roadside ditch intersects) provide information requested in next eight boxes. I Do culverts and travelways intersect at 90 degrees? x Yes No If not, identify location(s) and intersect angle(s), and justify the design(s): I _ Does drainage way alignment change within or near limits of culvert and surfaced I approaches thereto? x No Yes If"yes" identify location(s), describe change(s), and justification: IAre flumes or conduit to discharge into culvert barrel(s)? x No Yes If yes, identify location(s) and provide justification: I Are flumes or conduit to discharge into or near surfaced approaches to culvert ends? I c x No Yes If"yes" identify location(s), describe outfall design treatment(s): c .2 0 o E . Is scour/erosion protection provided to ensure long term stability of culvert structural 0 components, and surfacing at culvert ends? x Yes No If"no" Identify locations and provide justification(s): Will 100-yr flow and spread of backwater be fully contained in street ROW, and/or drainage easements/ROW? x Yes No if not, why not? [ Do appreciable hydraulic effects of any culvert extend downstream or upstream to Fneighboring land(s) not encompassed in subject property? x No Yes If "yes" describe location(s) and mitigation measures: I _ Are all culvert designs and materials in compliance with B-CS Tech. Specifications? X Yes No If not, explain in Special Design Section of this Part. fr. ISTORMWATER DESIGN GUIDELINES Page 21 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 r SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.13) Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) Is a bridge included in plans for subject property project? No Yes If"yes" provide the following information. ink Name(s) and functional classification of the roadway(s)? MO What drainage way(s) is to be crossed? U) a) a) AML W A full report supporting all aspects of the proposed bridge(s) (structural, geotechnical, hydrologic, and hydraulic factors) must accompany this summary report. Is the report provided? Yes No If"no" explain: U Is a Stormwater Provide a general description of planned techniques: Pollution Prevention Hay Bale Barriers and Rock Dams will serve as the U Ta Plan (SW3P) main protection against stormwater pollution. The 00 d established for Contractor shall use any other means necessary project construction? throughout construction. __No X Yes err Special Designs—Non-Traditional Methods Are any non-traditional methods (aquatic echosystems, wetland-type detention, natural stream replication, BMPs for water quality, etc.) proposed for any aspect of subject property project? W; X No Yes If"yes" list general type and location below. 1.11 rr IP wr Provide full report about the proposed special design(s) including rationale for use and expected benefits. Report must substantiate that stormwater management objectives will not qui be compromised, and that maintenance cost will not exceed those of traditional design solution(s). Is report provided? Yes No If"no" explain: lovo mu ■!1 STORMWATER DESIGN GUIDELINES Page 22 of 26 APPENDIX. D:TECH. DESIGN SUMMARY ,rr� Effective February 2007 As Revised February 2009 • SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.14) Pisa Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) Special Designs—Deviation From B-CS Technical Specifications If any design(s) or material(s) of traditional runoff-handling facilities deviate from provisions of B-CS Technical Specifications, check type facility(ies) and explain by specific detail element. Detention elements Drain system elements Channel features Culvert features Swales Ditches Inlets Outfalls Valley gutters Bridges(explain in bridge report) In table below briefly identify specific element,justification for deviation(s). Specific Detail Element Justification for Deviation (attach additional sheets if needed) 1) 2) 3) ' 4 5) I _ Have elements been coordinated with the City Engineer or her/his designee? For each item above provide"yes" or"no", action date, and staff name: 1) 2) 3) 4) 5) Design Parameters Hydrology rrr Is a map(s) showing all Design Drainage Areas provided? X Yes No Briefly summarize the range of applications made of the Rational Formula: ... For the Rational Formula we assumed residential areas had a runoff coefficient of 0.5 for large residential or estate lots. What is the size and location of largest Design Drainage Area to which the Rational Formula has been applied? 4.00 acres Location (or identifier): Ditch Line Culvert #1 STORMWATER DESIGN GUIDELINES Page 23 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY ✓ Part 4— Drainage Concept and Design Parameters Continued (Page 4.15) Design Parameters (continued) O1 Hydrology(continued) In making determinations for time of concentration, was segment analysis used? X No Yes In approximately what percent of Design Drainage Areas? As to intensity-duration-frequency and rain depth criteria for determining runoff flows, were any criteria other than those provided in these Guidelines used? X No Yes If"yes" identify type of data, source(s), and where applied: um Oka OP k For each of the stormwater management features listed below identify the storm return frequencies (year) analyzed (or checked), and that used as the basis for design. au Feature Analysis Year(s) Design Year Storm drain system for arterial and collector streets Storm drain system for local streets .�r Open channels Swale/buried conduit combination in lieu of channel Swales um Roadside ditches and culverts serving them 2,5,10,25,50, 10 0 25 & 100 Detention facilities: spillway crest and its outfall Detention facilities: outlet and conveyance structure(s) Detention facilities: volume when outlet plugged U Culverts serving private drives or streets Culverts serving public roadways Bridges: provide in bridge report. Hydraulics What is the range of design flow velocities as outlined below? I• Design flow velocities; 25 year Gutters Conduit Culverts Swales Channels No Highest(feet per second) 9.88 Lowest(feet per second) 8.38 UM Streets and Storm Drain Systems Provide the summary information outlined below: Roughness coefficients used: For street gutters: NA UI For conduit type(s) RCP 0.014 Coefficients: e l STORMWATER DESIGN GUIDELINES Page 24 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 OR rrc SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.16) Design Parameters(continued) Hydraulics (continued) +.. Street and Storm Drain Systems (continued) For the following, are assumptions other than allowable per Guidelines? Inlet coefficients? No Yes Head and friction losses No Yes ing Explain any"yes" answer: POIM In conduit is velocity generally increased in the downstream direction? Yes No Are elevation drops provided at inlets, manholes, and junction boxes? Yes No Explain any"no" answers: Are hydraulic grade lines calculated and shown for design storm? Yes No For 100-year flow conditions? Yes No Explain any"no" answers: sua What tailwater conditions were assumed at outfall point(s) of the storm drain system? Identify each location and explain: Open Channels If a HEC analysis is utilized, does it follow Sec VI.F.5.a? Yes No Outside of straight sections, is flow regime within limits of sub-critical flow? x Yes No If"no" list locations and explain: *1190 Culverts If plan sheets do not provide the following for each culvert, describe it here. For each design discharge, will operation be outlet(barrel) control or inlet control? All culverts will be inlet controlled. Entrance, friction and exit losses: A 0.5 entrance and exit loss coefficients are used for sloped end treatments and square edged headwalls with wingwalls. PIM Bridges Provide all in bridge report 4161,* STORMWATER DESIGN GUIDELINES Page 25 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY OF Part 4— Drainage Concept and Design Parameters Continued (Page 4.17) Design Parameters(continued) mo Computer Software What computer software has been used in the analysis and assessment of stormwater management needs and/or the development of facility designs proposed for subject property project? List them below, being sure to identify the software name and version, the date of the version, any applicable patches and the publisher Open Office Calculator Spreadsheet ifita N imito Part 5— Plans and Specifications Requirements for submittal of construction drawings and specifications do not differ due to use of a rak Technical Design Summary Report. See Section III, Paragraph C3. OP Part 6 — Conclusions and Attestation Conclusions MP Add any concluding information here: The Indian Lakes Subdivision, Phase 19 will have no adverse impact to downstream properties and conforms to the overall subdivision report. OP rim tie MOW Attestation G` Provide attestation to the accuracy and completeness of the foregoing 6 Parts of this Technical Design Summary Drainage Report by signing and sealing below. "This report(plan) for the drainage design of the development named in Part B was prepared by me (or under my supervision) in accordance with provisions of the Bryan/College Station Unified Drainage Design Guidelines for the owners of the property. All licenses and permits required by any and all state and federal regulatory agencies for the proposed drainage improvements have been issued or fall under applicable general permits." 3 (Affix Seal) w�r•� n °• .��ar Licer a ofessional Engineer /JEFFE ,Y 7.-.':0E3rRISC;\ 91.{-/45- , r 3 State of Texas PE No. (` - , S 7 ,1 3 ....... ll� STORMWATER DESIGN GUIDELINES Page 26 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 EXHIBIT B Drainage Area Map Drainage Report Indian Lakes, Phase 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i 1 1 1 1 1 1 EXHIBIT C- 1 1 Rational Method Calculations 1 II!;! Drainage Report Indian Lakes, Phase 19 p 1 1 1 1 1 1 1 1 1 1 1 1 14) N In N 00 1,0 w M I) N V N N O ▪ N r r 0041 = V V 7 V 7 C N. co V N- 0 09O y c0 0 o cc). r M N r O) U r N r 0 0 In 0 0 091= r- rrrr C - 0 CO (0 0 0 AZO N 1°' °°- (°' in' T - co U r N r r O (0 (0 (0 (0 W N CO 0 9ZI= O a) 0) 0) O C 0 (0 M 0 (0 04� 0 N N M N M .- 0') G0 (5) 0) N... U r CO (o (D (o (.9 0H= 0) 6 CO CO 0 C - 0) N- r 0) 0) - N M r (n gb w CO CO co (O C p I- N- N- 911 - 511 I- N- N- N- N.: as _ C V CO N V � ZO c6 (.6 U o) 0 M M M M M co co co CO CO i) y Z I= (0 6 (0 (0 6 R (� " O O O O 0 al a13Sn E00000 to CO .c d 0) CONMu) 31'oleo £ m cd CO N X o -I V". (CI scorn uJ 7 l�l1OO13A yrrrrr E c -i'11f d (0 co (0 co co p (n co n 6 U- MOld a311nO iv 00000 HLJN31 0) (6r; 66 4 MOld'd11110 NN 47. 11Vd co co CO co m 6N.: coa) r MOld ONv1213A0 a) a) a) a) a) H15N31 rCO r°' 'rt MO1d GNV12:13A0 N- N CO I,- (f) 0 r 0 0 CO VO 1tf1O1 r r o 0) 0 0 0 0 0 IN3111I3AVdDo6666 IC) co M (o CO O 1d11N3O1S3a o N r r O N C N N O O O O O M O3dO13A3ONn ▪ 0 O 0 0 N MM (oMM_ N r r V3Id 1\1101 U• N V N N• N Q V38V 30VNIb21O 2 4 w 1 i 1 1 1 1 1 1 1 1 1 I I EXHIBIT C-2 Culvert Sizing Calculations I I I L I II Drainage Report Indian Lakes, Phase 19 IP 1 1 I I I I 1 1 1 I I D a r x H w CO � LO 0- L0 / y I, 6 l0 W N r O N V• I� O I Q "O O O '- I I 0 I I N a « , '- a) a) a) a) a) 0 PP a I I c Oo , o 0 c c c c c o I I H y I I R p] o I co co co co co 0 W N N N N N y _0 r 00 co R 0')I I C) U (n p 0 0- CO r` N CO J N N N CO M I ' U O = N �' V w c0 00 c0 C 00 m N N N N N I v ° a Q O :'O c OO 0) N UJ r In al 0) 0 � I c0 rd' W 0) I• ► wc J. �C Orrrr I I `6 . 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V' f� V tD I I O N LO UD m r r II pI I N U) 0 0 Ul N ) P4 I I c E > > > > > o F cOO000 HO) N m M I E aO O` j LU O co. r co. (v Cn V 0 U w N N N N N I I ) a) I I 2 U d O 0 I O M 0') CO J (D O (.5 (15 CO 1 I U rn- N �' c w . 0000 .0 . NNNNN I I 0 o I 01 0 � .O t0 O O O m -6 ' 0 _ 0 S t- (T N m m l".1m..,. II 0. 2 my V OOrr ,- C J 1 I c t Uo I m w a\o ° w o 3 n O J p O H W z O M m O O Or M (hM V V U r 7 z W Z J U g N H N s s N < 0 V V s 0 O D 0 r r r r r 0 ... U J > Q N U U U o,_0 m r-`U O (DU700 0w -577Nm.co. N J H CC co Q rrrr .- U Z 0 i (= < (T7 Oac') w mN (D _ a V) --."0H00000 X W e W J CV U L L D N N D 0 Nm o .6r.o LN- cm , v L ,!>_,16. nu) commwmmmmm = UJ V N N N N N 7-. R JO CO "CH-. ' o J h _ H L w e r) O l5 z : . ,, , (D M D rn v n U "N NN L F- S4- 0 w S J N + J O Z r r r r '-r5., D L 11x1 O - „... 00 ./-n c m v W ii2 ,,, i-u ,-,0 > ',----V' N V' t0 tD + II = o W iI Z W N 7' Li =E, In m O O V Oo 0 0 0 0 0 Z m L p 0 L U 0 UD LU O O m N r N M M E Z a r U N- dI r .-- r r co U O a OLi ° d _ D V N R U 3 1_01 co (h m O e0 .O 0 .5 0 4- .Ui m UP ONcsi U n w N I = @ 0 r (7 N V N QC h w .Ui m O) r W C s.v -° o �o y o f M U .D_ LD ] .N O N 11 a m r d o O r II 00 O U 0 ' w t c p c m 0 C O a o 01 m N U a°U = ? it It 0 of a 0 m O I c r O U PIP 7 U O 6 U 1 1 1 1 1 1 1 1 1 1 1 i 1 1 1 EXHIBIT C-3 Ditch Capacity Calculations w Drainage Report Indian Lakes, Phase 19 t 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 v C '0 2 0 iR ! C w E '-g j ; h au) C5 cu 0 > ~ Wck, 'Ji m m e. //\ L 4 �� • d , ce '/\� oar I\/ \` • • o CO C Nv 1 CD W m s CO -.--, -4 II J w . ,1_ I °' CO• N CO 4k II L.N 1 0 m � 0 o 'L (L) 111 z `�M� 0 i. rI 'v N\ O N o 21 v II o of mi 0 IA I0 GI co m M Wo c/3Q ` '' O Z CO• U I� 'i/ II LV p Z 2 Q A v W t/ a W v II U /, pr o 0 °\ U v ,,A- Car ?< c p 0 c�6' X W I t 1 1 1 I . 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 111 1 1 DRAINAGE REPORT FOR INDIAN LAKES SUBDIVISION PHASE 19 December 2014 PREPARED FOR: SMILING MALLARD DEVELOPMENT, LTD. 3608 EAST 29TH STREET BRYAN, TEXAS 77802 iro 979-846-4384 I , IMBESI No. 10620046 I pp McCLURE & BROWNE ENGINEERING/SURVEYING, INC. 01 1008 Woodcreek Dr.,Suite 103•College Station,Tx.77845•(979)693-3838 Engineer Reg.No.F-458 _ Survey Reg.No. 101033-00 1 1 1 1 1 1 1 i 1 1 1 1 1 1 1 1 1 1 Indian Lakes Subdivision, Phase 19 Stormwater Management Technical Design Summary Report MBESI No. 10620046 PART 1 —Executive Summary Report fiwo Section 1 —Contact Information Project Designer: McClure and Browne Engineering and Surveying, Inc. 1008 Woodcreek Drive, Suite 103 College Station, TX 77845 979-693-3838 Project Developer: Smiling Mallard Development, Ltd. 3608 East 29th Street Bryan, Texas 77802 Section 2—General Information and Project Location This development is the 19th phase of a multi-phase subdivision. Phase 19 consists of 16 lots. The phase is located in the Indian Lakes Village which is down Arrington Rd. approximately 2 miles from the Arrington Rd. William D. Fitch Pkwy intersection. Phase 19 lies in the northeast portion of the subdivision near the intersection of Mesa Verde Drive and Sundance Drive. The entire subdivision has been analyzed in the initial drainage report submitted in September, 2000. The development is located within the ETJ of College Station. The project site is in the Peach Creek watershed. According to the Flood Insurance Rate Maps for Brazos County, Texas and incorporated area, Map Number 48041C0350E effective May 16, 2012; no portion of this property is located in a 100-year flood hazard area. Culvert pipe and ditch sizing calculations are shown with this submittal. The culverts and ditches peak runoffs were found using the Rational Method. A runoff coefficient (c) of 0.50 was used for residential areas since all the lots have an area greater than 1 acre. The ditches along the proposed roadways are uniform throughout the project. The ditch profiles along all proposed roadways were determined using the largest ditch drainage area found for Phase 19. The culverts and ditches were analyzed using an Excel Spreadsheet which utilizes Manning's Equation for the analysis. tish Section 3 —Reference Exhibit A Technical Design Summary Exhibit B Drainage Area Map Exhibit C-1 Rational Method Calculations Exhibit C-2 Culvert Sizing Calculations Exhibit C-3 Ditch Capacity Calculations vm Drainage Report Indian Lakes, Phase 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 flfM tikom bow EXHIBITS 466 O Drainage Report Indian Lakes, Phase 19 i i i i i i i 911. rx dna EXHIBIT A Technical Design Summary 6116* ere Sire Woe Drainage Report Indian Lakes, Phase 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY The Cities of Bryan and College Station both require storm drainage design to follow these Unified Stormwater Design Guidelines. Paragraph C2 of Section III (Administration) requires submittal of a drainage report in support of the drainage plan (stormwater management plan) proposed in connection with land development projects, both site projects and subdivisions. That report may be submitted as a traditional prose report, complete with applicable maps, graphs, tables and drawings, or it may take the form of a "Technical Design Summary". The format and content for such a summary report shall be in substantial conformance with the description in this Appendix to those Guidelines. In either format the report must answer the questions (affirmative or negative) and provide, at minimum, the information prescribed in the "Technical Design Summary" in this Appendix. The Stormwater Management Technical Design Summary Report shall include several parts as listed below. The information called for in each part must be provided as applicable. In addition to the requirements for the Executive Summary, this Appendix includes several pages detailing the requirements for a Technical Design Summary Report as forms to be completed. These are provided so that they may be copied and completed or scanned and digitized. In addition, electronic versions of the report forms may be obtained from the City. Requirements for the means (medium) of submittal are the same as for a conventional report as detailed in Section III of these Guidelines. Note: Part 1 — Executive Summary must accompany any drainage report required to be provided in connection with any land development project, regardless of the format chosen for said report. Note: Parts 2 through 6 are to be provided via the forms provided in this Appendix. Brief statements should be included in the forms as requested, but additional information should be attached as necessary. Part 1 — Executive Summary Report Part 2— Project Administration Part 3— Project Characteristics Part 4— Drainage Concept and Design Parameters Part 5— Plans and Specifications Part 6—Conclusions and Attestation STORMWATER MANAGEMENT TECHNICAL DESIGN SUMMARY REPORT Part 1 — Executive Summary This is to be a brief prose report that must address each of the seven areas listed below. Ideally it will include one or more paragraphs about each item. 1. Name, address, and contact information of the engineer submitting the report, and of the land owner and developer (or applicant if not the owner or developer). The date of submittal should also be included. 2. Identification of the size and general nature of the proposed project, including any ,AW proposed project phases. This paragraph should also include reference to applications that are in process with either City: plat(s), site plans, zoning requests, STORMWATER DESIGN GUIDELINES Page 1 of 26 APPENDIX. D:TECH. DESIGN SUMMARY etw Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY or clearing/grading permits, as well as reference to any application numbers or codes assigned by the City to such request. 3. The location of the project should be described. This should identify the Named Regulatory Watershed(s) in which it is located, how the entire project area is situated therein, whether the property straddles a watershed or basin divide, the approximate acreage in each basin, and whether its position in the Watershed dictates use of detention design. The approximate proportion of the property in the gp city limits and within the ETJ is to be identified, including whether the property straddles city jurisdictional lines. If any portion of the property is in floodplains as described in Flood Insurance Rate Maps published by FEMA that should be disclosed. 4. The hydrologic characteristics of the property are to be described in broad terms: existing land cover; how and where stormwater drains to and from neighboring properties; ponds or wetland areas that tend to detain or store stormwater; existing creeks, channels, and swales crossing or serving the property; all existing drainage easements (or ROW) on the property, or on neighboring properties if they service runoff to or from the property. 5. The general plan for managing stormwater in the entire project area must be outlined to include the approximate size, and extent of use, of any of the following features: storm drains coupled with streets; detention / retention facilities; buried conveyance conduit independent of streets; swales or channels; bridges or culverts; outfalls to principal watercourses or their tributaries; and treatment(s) of existing watercourses. Also, any plans for reclaiming land within floodplain areas must be to outlined. 6. Coordination and permitting of stormwater matters must be addressed. This is to include any specialized coordination that has occurred or is planned with other OP entities (local, state, or federal). This may include agencies such as Brazos County government, the Brazos River Authority, the Texas A&M University System, the Texas Department of Transportation, the Texas Commission for Environmental Quality, the US Army Corps of Engineers, the US Environmental Protection Agency, et al. Mention must be made of any permits, agreements, or understandings that pertain to the project. 7. Reference is to be made to the full drainage report (or the Technical Design Summary Report) which the executive summary represents. The principal elements of the main report (and its length), including any maps, drawings or construction documents, should be itemized. An example statement might be: we "One -page drainage report dated , one set of — construction drawings ( sheets) dated , and a -page specifications document dated comprise the drainage report for this project." Wit OR OW ■r le STORMWATER DESIGN GUIDELINES Page 2 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 4W SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 2 — Project Administration Start (Page 2.1) Engineering and Design Professionals Information Engineering Firm Name and Address: Jurisdiction City: Bryan McClure & Browne Engineering/Surveying, Inc. 1008 Woodcreek Drive, Suite 103 X College Station College Station, Texas 77845 Date of Submittal: (979) 693-3838 464. Lead Engineer's Name and Contact Info.(phone, e-mail,fax): Other: Jeffery L. Robertson, P.E. .w Supporting Engineering/Consulting Firm(s): Other contacts: ftw Developer/Owner/Applicant Information Developer/Applicant Name and Address: Phone and e-mail: 41m" Smiling Mallard Development, Ltd. (979) 846-4384 3608 East 29th Street w Bryan, Texas 77802 Property Owner(s) if not Developer/ Applicant(&address): Phone and e-mail: it Project Identification Development Name: Indian Lakes, Phase 19 Is subject property a site project, a single-phase subdivision, or part of a multi-phase subdivision? Multi-phase Subdivision If multi-phase, subject property is phase 19 of Legal description of subject property(phase)or Project Area: (see Section II, Paragraph B-3a) 00 Indian Lakes, Phase 19 bow If subject property(phase) is second or later phase of a project, describe general status of all earlier phases. For most recent earlier phase Include submittal and review dates. so The project is the 19th phase of a multi phase subdivision. At this time the first phase has 60 been built. Phase 1 was submitted in September, 2000 and consisted of 58 lots. The most recent phase submitted was Ph. 25. General Location of Project Area, or subject property(phase): Project site is located near the intersection of Mesa Verde Drive and Sundance Drive in College Station, Texas. In City Limits? Extraterritorial Jurisdiction (acreage): a. Bryan: acres. Bryan: College Station: 34.48 osift College Station: acres. Acreage Outside ETJ: mw em STORMWATER DESIGN GUIDELINES Page 3 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 OP SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 2 — Project Administration Continued (page 2.2) Project Identification (continued) Roadways abutting or within Project Area or Abutting tracts, platted land, or built subject property: developments: Mesa Verde Drive Indian Lakes, Phase 16 & Undeveloped Land I Named Regulatory Watercourse(s)&Watershed(s): Tributary Basin(s): The nearest tributary is Peach Creek S. Phase 19 is located in the Peach Creek Watershed. Tributary 7.2 (See FEMA Map 48041C0350E) . Plat Information For Project or Subject Property(or Phase) Preliminary Plat File#: Final Plat File#: Date: Name: Pending Approval Status and Vol/Pg: Pending Approval If two plats, sec. . - Ftt Status: e ._ -• Zoning Information For Project or Subject Property(or Phase) Zoning Type: Existing or Proposed? Case Code: Case Date Status: Zoning Type: Existing or Proposed? Case Code: Case Date Status: Stormwater Management Planning For Project or Subject Property(or Phase) nning Conference(s) & Date(s): Participants: 4W Preliminary Report Require.' Submittal Date -eview Date Review Comments Addressed? Yes No In Wr ' g? When? Compliance With Preliminary Drainage R- :•rt. a efly describe (or attach documentation explaining)any deviation(s)from provisions of P' inary Drainage Report, if any. rrr STORMWATER DESIGN GUIDELINES Page 4 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX at, APPENDIX D — TECHNICAL DESIGN SUMMARY Part 2 — Project Administration Continued (page 2.3) L _ Coordination For Project or Subject Property(or Phase) Note: For any Coordination of stormwater matters indicated below, attach documentation describing and substantiating any agreements, understandings, contracts, or approvals. Dept. Contact: Date: Subject:_ Coordina is I With Other Departmentson of Ju -Jurisddiction City(Bryan or _ "" College Station in Coordination With mmarize need(s)&actions taken (include contacts &dates): Non-jurisdiction City Needed? Yes No X Coordination with Summarize need(s : actions taken (include contacts : sates): r Brazos County Needed? Yes No X Coordination with Summarize need(s)&actions take. in de contacts&dates): TxDOT Needed? Yes No X 5 Coordination with Summarize ne=. s)&actions taken (include contacts &da : TAMUS Needed? , iii Yes No X Permits For Project or Subject Property(or Phase) As to stormwater management, are permits required for the proposed work from any of the entities 1 r listed below? If so, summarize status of efforts toward that objective in spaces below. ism Permitted or Entity Approved ? Status of Actions (include dates) US Army Crops of j Engineers No X Yes 1 US Environmental Protection Agency No X Yes I Texas Commission on Environmental Quality A Stormwater Pollution Prevention Plan must be implemented prior to the start of construction according to TPDES General Permit No. TXR150000. No Yes x Brazos River Authority No X Yes I t 1 STORMWATER DESIGN GUIDELINES Page 5 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX fro APPENDIX D - TECHNICAL DESIGN SUMMARY Part 3 — Property Characteristics Start (Page 3.1) Nature and Scope of Proposed Work .W Existing: Land proposed for development currently used, including extent of impervious cover? OR Existing undeveloped land (Dense tree cover) . Existing impervious cover is approximately 0 sf. Site -•evelosment of one platted lot, or two or more adjoining slat -- . s. Development Building on a • e platted lot of undeveloped la •. Project Building on two or more p a -- .d'.. • ots of undeveloped land. OR (select all Building on a single I. , • adjoining lots, : - srososed plat will not form applicable) a new stre- :. may include ROW dedication to e•' '•• streets). er(explain): Subdivision X Construction of streets and utilities to serve one or more platted lots. Development Construction of streets and utilities to serve one or more proposed lots on Project OR lands represented by pending plats. Site projects: building use(s), approximate floor space, impervious cover ratio. Describe Subdivisions: number of lots by general type of use, linear feet of streets and Nature and drainage easements or ROW. Size of This phase of the subdivision includes 16 lots. The development VI Proposed consists of approximately 3,177 LF of streets with 16' PUE on each Project side of the streets ROW. U Is any work planned on land that is not platted '- , -.slain: or on land for which platting is not pending? X No _ Yes FEMA Floodplains Is any part of subject property abutting a Named Regulatory Watercourse No X Yes (Section II, Paragraph B1)ora tributary thereof? Is any part of subject property in floodplain No Yes X Rate Map 48041C0350E area of a FEMA-regulated watercourse? Encroachment(s) sis Encroac _• •urpose(s): Building site(s) Roang(s) into Floodplain areas planned? Utility crossing(s) •ther(ex. ..• . 1. No X ift Yes OR •.: areas not shown on Rate Maps, has work been done toward amending the F approved Floc). •: • define allowable encroachments in proposed are- ail I>All STORMWATER DESIGN GUIDELINES Page 6 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 mo SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 3— Property Characteristics Continued (Page 3.2) Hydrologic Attributes of Subject Property(or Phase) Has an earlier hydrologic analysis been done for larger area including subject property? bwYes Reference the study(&date) here, and attach copy if not already in City files. Indian Lakes Subdivision; September, 2000 X 110f Is the stormwater management plan for the property in substantial conformance with the earlier study? Yes X No If not, explain how it differs. No sect property is not part of multi-phase project, describe stormwater manageme plan for : .roperty in Part 4. If property is part . Iti-phase project, provide overview of stormw. - management plan for Project Area here. In =:• 4 describe how plan for sub.- • operty will comply therewith. irr Do existing topographic features on subject property store or detain runoff? X No Yes ,.. Describe them (include approximate size, volume, outfall, model, etc). Ow sm Any known drainage or flooding problems in areas near subject property? X No Yes wr Identify: Based on location of study property in a watershed, is Type 1 Detention (flood control)needed? (see Table B-1 in Appendix B) Detention is required. X Need must be evaluated. Detention not required. What decision has been reached? By whom? Detention study during Phase 1. "a• If the need for How was determination made? Type 1 Detention Ow must be evaluated: Detention was required and is provided for the entire Indian Lakes Subdivision. However, Phase 19 does not require aro any additional detention. 0. 0. STORMWATER DESIGN GUIDELINES Page 7 of 26 APPENDIX. D:TECH. DESIGN SUMMARY go Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 3 — Property Characteristics Continued (Page 3.3) Hydrologic Attributes of Subject Property(or Phase) (continued) Does subject property straddle a Watershed or Basin divide? x No Yes If yes, describe splits below. In Part 4 describe design concept for handlin. this. Watershed or Basin Larger acreage Lesse - - . .e ■ U Above-Project Areas(Section II, Paragraph B3-a) ` Does Project Area (project or phase)receive runoff from upland areas? x No Yes Size(s)of area(s) in acres: 1) 2) 3) 4) lop Flow Characteristics (each instance) (overland sheet, shallow concentrated, recognizable concentrated section(s), small creek (non-regulatory), regulatory Watercourse or tributary); Overland flow to prcposed ditch lines on Phase 19 streets. 3 3 Flow determination: Outline hydrologic methods and assumptions: The Rational Method was used for flow calculations and the post development land was treated as large acre residential tracts. • Does storm runoff drain from public easements or ROW onto or across subject property? OP X No Yes If yes, describe facilities in easement or ROW: Are changes in runoff characteristics subject to change in future? Explain No, upstream land is already developed. MO Conveyance Pathways (Section II, Paragraph C2) Must runoff from study property drain across lower properties before reaching a Regulatory Watercourse or tributary? No x Yes tom Describe length and characteristics of each conveyance pathway(s). Include ownership of property(ies). Runoff from Ph. 19 will leave the phase and be discharged into existing WO tributaries of Peach Creek. The property is a future phase of the :Cndian Lakes Subdivision. S a STORMWATER DESIGN GUIDELINES Page 8 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 .SA SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 3 — Property Characteristics Continued (Page 3.4) Hydrologic Attributes of Subject Property(or Phase) (continued) Conveyance Pathways(continued) Do drainage es,for what part of length? % Created by? plat, or easements instrument. If instrument(s), describe their provisions. exist for any "`" part of pathway(s)? X No Yes Where runoff must cross lower p .•erties, describe charac ' istics of abutting lower property(ies). (Existing watercourse Easement or Co, ent squired?) , E,„ Pathway Areas r it Describe any built or impr•-ed drainage facilities existing nea e property(culverts, bridges, lined channels •uried conduit, swales, detention ponds, -tc). Nearby Drainage Do any of these have hydrologic or hydraulic influence on proposed stormwater Facilities design? X No Yes If yes, explain: ittro IOW .r.r STORMWATER DESIGN GUIDELINES Page 9 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Start (Page 4.1) Stormwater Management Concept Discharge(s) From Upland Area(s) a off is to be received from upland areas,what design drainage features will be used to accomm..: - it and insure it is not blocked by future development? Describe fo -- area, flow section, or .i -- .e point. NIP 110 I Discharge(s)To Lower Property(ies) (Section II, Paragraph E1) Does project include drainage features (existing or future) proposed to become public via platting? x No Yes Separate Instrument? X No Yes 'er Guidelines reference above, how will Establishing Easements(Scenario 1) ru off be discharged to neighboring Pre-development Release(Scenari, ) prop- (ies). Combination of the two Scenario: Scenario 1. If easements are proposed, describe where needed,and provide stat . of actions on each. (Alta• ed Exhibit# 1 Scenario 2: Provide general de ription of how release(s)wil .e managed to pre-development conditions(detention, sheet flow, p: ially concentrated, et . . (Attached Exhibit# 1 Combination: If combination is prop sed, explain how di harge will differ from pre- development conditions at the pr..erty line for each area (o .oint)of release. U e If Scenario 2, o ombination are to be used, has proposed design been coor.. ated with owner(s)of r- eiving property(ies)? No Yes Explain and pro .e documen , ion. OM STORMWATER DESIGN GUIDELINES Page 10 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 W. SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.2) Stormwater Management Concept (continued) Within Project Area Of Multi-Phase Project b.' •-. ' gaining Basins or Watersheds and acres shifting: Will project result ""' in shifting runoff between Basins or i" between What design and mitigation is us-: • pensate for increased runoff Watersheds? from gaining basin or watersh-• . x No Yes How will runoff from Project 1. With facility(ies) involving other development projects. Area be mitigated to pre- 2. Establishing features to serve overall Project Area. development conditions? Select any or all of 1, 2, 3. X On phase(or site) project basis within Project Area. and/or 3, and explain below. . _'tared facilit (type&location of facility; design drainage area served; relationship to siz- Project • -- : (Attached Exhibit# 2. For Overall Project Area (type&loc. of facili i- • Attached Exhibit# ors 411. 3. By phase (or site) project: Describe planned mitigation measures for phases (or sites) in subsequent questions of this Part. o,,, • - aquatic echosystems proposed? No Yes In which phase(s)or projec ? Nig �. a a> u, .�. r Are other Best Manag- •-nt Practices for reducing stormwate :• lutants proposed? rr. � No Yes Su '.rize type of BMP and = ent of use: '� o Z t""' •° If design of any runoff-handlin• .cilities deviate from p : isions of B-CS Technical x Specifications, check ty.- acility(ies)and explain in later q - ions. n Detention - • ents Conduit elements Cha --I features Sw. - Ditches Inlets Valley gutters •. .IIs Culvert features Bridges Other rrr 10110 STORMWATER DESIGN GUIDELINES Page 11 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.3) Stormwater Management Concept (continued) Within Project Area Of Multi-Phase Project(continued) Will Project Area include bridge(s)or culvert(s)? No x Yes Identify type and general size and In which phase(s). Culvert #1 - 24" RCP Pipe on Chaco Canyon Drive Culvert #2 - 24" RCP Pipe on Halona Court iiii •- -• '• /retention serves(will serve)overall Project Area, describe how it relates to -;- phase phase or site p •' . • ical location, conveyance pathway(s), constru -quence): I Within Or Serving Subject Property(Phase, or Site) • :_-• •art of larger Project Area, is design in substantial conform.• - I i earlier analysis " and report for . a - - -a? Yes No, then •• - .raze the difference(s): .r Identify whether each of the types of drainage features listed below are included, extent of use, 1 and general characteristics. Typical shape? Surfaces? c•-• V-Shape Grass 3 m Steepest side slopes: Usual front slopes: Usual back slopes: y 4:1 4:1 4:1 x Flow line slopes: least o.68% Typical distance from travelway: 11' tt Varies (Attached Exhibit# ) -to o typical greatest 2.93% 13 z I cts 2 Are longitudinal culvert ends in compliance with B-CS Standard Specifications? Qx Yes No,then explain: v, • -rsections or otherwise, do valley gutters cross arterial or collector stre- �• I }Yes If yes explain: 0 -o L fA C/3 A Are valley gutters proposed to cross - , -- away from an intersection? aa) =z No Yes Explain. -. •er of loca • -_9 IIS a cNI m m X Q up Ili Mr STORMWATER DESIGN GUIDELINES Page 12 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.4) Stormwater Management Concept (continued) Within Or Serving Subject Property(Phase, or Site) (continued) . tter line slopes: Least Usual Greatest pm Are i ets recessed on arterial and collector streets? Yes No "no", identify here and why. ilia !" Will inlets captu : 10-year design stormflow to prevent flooding of' tersections (arterial rr with arterial or colle. or)? Yes No If no, expl.' where and why not. m [ En Will inlet size and placemen .revent exceeding allowa� e water spread for 10-year `m design storm throughout site (e abase)? Y-: No If no, explain. rn m o Sad curves: Are inlets placed at low poin Yes No Are inlets and conduit sized to prevent 100-year storm • rom ponding at greater than 24 inches? L• o Yes No Explain "no"answe a) a) I Q Will 100-yr stormflow b- ontained in combination of ROW a • buried conduit on whole length of all str-ets? Yes No If no, des 'be where and why. I Do desig - for curb, gutter, and inlets comply with B-CS Technical Specific. 'ons? es No If not, describe difference(s)and attach justification. • - any 12-inch laterals used? No Yes Identify length(s)and wher- ' use.. a Pipe runs between tern Typical Longest I I = } access points (feet): 92 Are junction boxes used at each .- d? Yes No If not, explain where u) and why. , c o 1 �° z a E x 1I V) downstream soff : .t or below upstream soffits? Leas =• ount that hydraulic n Yes N. If not, explain where and why: grade line • .elow gutter line (system-wide): I STORMWATER DESIGN GUIDELINES Page 13 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX Of APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.5) Stormwater Management Concept(continued) OM Within Or Serving Subject Property(Phase, or Site) (continued) N Describe watercourse(s), or system(s) receiving system discharge(s) below (include design discharge velocity, and angle between converging flow line . 1) atercourse (or system), velocity, and angle'? U U c 2) Watercourse system), velocity, and angle? liaU C o C o c E 3)Watercourse(or system), veloci . . angle? +. T0) 9- c O 2 0 a Q E � For each outfall abov-, what measures are taken to . event erosion or scour of 8 receiving and all ilities at juncture? CI) a? 1) 1 n3 2) m 3) • - swale(s)situated along property lines between properties? No s Num.-r of instances: For each instance answer the following questio Surface tr- ments (including low-flow flumes if any): IR �. EL) u) } Flow line slopes (minimum . -. maximum): 0 z Outfall characteristics for each (veloc' q, conver.: t angle, &end treatment). m .r CD X N U m _ Q Will 100-year desi.• storm runoff be contained within easement(s .r platted drainage "i ROW in all inst. ces? Yes No If"no"explain: 0 mit U STORMWATER DESIGN GUIDELINES Page 14 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 .. SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.6) Stormwater Management Concept (continued) Within Or Serving Subject Property(Phase, or Site) (continued) Are roadside ditches used? No X Yes If so, provide the following: rIs 25-year flow contained with 6 inches of freeboard throughout? X Yes No [ o Are top of banks separated from road shoulders 2 feet or more? X Yes No Are all ditch sections trapezoidal and at least 1.5 feet deep? Yes X No 0 For any"no"answers provide location(s)and explain: CD Il lal (13 All Ditches are V-shaped and at least 2' deep 0I conduit is beneath a swale, provide the following information (each instance). Ins -nce 1 Describe general location, approximate length: >- Is 100-ye- design flow contained in conduit/swale combination? Ye No If "no"expla' a) o IC a Space for 100-ye:r storm flow? ROW Z c Easement With Swale Surface ty.-, minimum Conduit Type and size, minim and maximum and maximum slopes: slopes, design storm: cI :. C- -0 a) m Inlets Describe how condui 's loaded (from streets/stor r drains, inlets by type): c T c CO c t U 2 O c Access Describe how maintenance . cess is p .vided (to swale, into conduit): o ami o c •E .0 Instance 2 Describe general location, .ppro ate length: E O ca [ cn • cp c Is 100-year design flow containe. in conduit/swale cal bination? Yes No O o If "no"explain: m L E • a) Space for 100-year storm 'ow? ROW Easement Width O a Swale Surface type, imum Conduit Type and size, mi um and maximum aand maximum slope - slopes, design storm: o a Inlets Describe ow conduit is loaded (from streets/storm drains, inl- by type): a) m c 0 0 I I ¢ Access aescribe how maintenance access is provided (to swale, into condu : I I STORMWATER DESIGN GUIDELINES Page 15 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.7) I Stormwater Management Concept (continued) Within Or Serving Subject Property(Phase, or Site) (continued) in "yes" provide the following information for each instance: as Inst. ce 1 Describe general location, approximate length, surfacing: (13 c p so ow o ui Is 100-year design .w contained in swale? Yes No Is swale wholly • c y within drainage ROW. Yes No Explain "no" . swers: a) 111 00Access Describe how mainte Ince access is provide. i 0 z c Instance 2 Describe general location, ap7 ximate length, surfacing: a) �• o E mIs 100-year design flow co :lined in swale? Yes No Is swale wholly m o within drainage ROW? Yes No Explain "no' .nswers: 3 fX Access Descr', how maintenance access is provided: .9 d Ins =nce 3,4, etc. If swales are used in more than two instances, attach sheet • oviding all above information for each instance. _ -w" channels: Will any area(s)of concentrated flow be channelized (deepenedum wide _. or straightened)or otherwise altered? No Yes If only s tly shaped, s- "Swales" in this Part. If creating side banks, provide informati.• •elow. p .c Will design repli : e natural channel? Yes No If"no" .r each instance nil o Q describe section sha.: &area, flow line slope (min. &max.), s •.ces, and 100-year o w design flow, and amount . reeboard: °- Instance 1: cC a) E o'o Instance 2: L 0_ E Q z 71) c x Instance 3: U STORMWATER DESIGN GUIDELINES Page 16 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 iw SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.8) Stormwater Management Concept (continued) Within Or Serving Subject Property(Phase, or Site) (continued) xisting channels (small creeks): Are these used? No Yes I "yes" provide the information below. �,. Wi small creeks and their floodplains remain undisturbed? Yes No How man disturbance instances? Identify each planned location: YIN For each location, describe length and general type of proposed improv-ment (including floc).slain changes): For each location, des. ibe section shape &area, flow line sl..e (min. & max.), surfaces, and 100-year .-sign flow. 0 Mfr. c • Watercourses (and tributaries): -ide from fri .e changes, are Regulatory gin Watercourses proposed to be altered 0,o Yes Explain below. • Submit full report describing proposed c' .n.,-s to Regulatory Watercourses. Address existing and proposed section size and sh.4.e, surfaces, alignment, flow line changes, > length affected, and capacity, and provid• f documentation of analysis procedures 2and data. Is full report submitted? =s No If"no"explain: E Tu . All Proposed Channel Work: or all proposed chan el work, provide information requested in next three boxe . If design is to replicate nat al channel, identify location a . length here, and describe design in Special Design -ection of this Part of Report. Will 100-year flo be contained with one foot of freeboard? Y- No If not, identify loc.. ion and explain: I Are RI /easements sized to contain channel and required maintenance spate? es No If not, identify location(s)and explain: 1 STORMWATER DESIGN GUIDELINES Page 17 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY or 1111. Part 4— Drainage Concept and Design Parameters Continued (Page 4.9) us Stormwater Management Concept (continued) Within Or Serving Subject Property(Phase, or Site) (continued) ow many facilities for subject property project? For each provide info. belo . F. each dry-type facilitiy: Facility 1 Facility 2 Acre served &design volume + 10% 100-yr ,olume:free flow& plugged Design di• harge (10 yr&25 yr) Spillway cre• at 100-yr WSE? yes no y-s no Berms 6 inche above plugged WSE? yes no yes no Explain any"no" . swers: For each facility what is 25- design Q, and design of out -t structure? Facility 1: IP 0 Z Facility 2: X Do outlets and spillways discharge 1'to a public fa,ility in easement or ROW? Facility 1: Yes No Facilit, 2: Yes Noon " 0 If"no"explain: a)a) 0 o o- For each, what is velocity of 25-yr desi. disch:rge at outlet? &at spillway? 0 Facility 1: & Faci' 2: & Are energy dissipation measures .ed? No Yes Describe type and wr v location: c , 0 c a) MP c a For each, is spillway su .ce treatment other than concrete? es or no, and describe: "` Facility 1: Facility 2: For each, what ► easures are taken to prevent erosion or scour at rec='ving facility? Facility 1: Facility 2: If berm are used give heights, slopes and surface treatments of sides. Facili 1: oris ,/acility 2: +■� eit w STORMWATER DESIGN GUIDELINES Page 18 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.10) Stormwater Management Concept(continued) i.. Within Or Serving Subject Property(Phase, or Site) (continued) :: tructures comply with B-CS Specifications? Yes or no, and explain if"no": Facility 1; ai n' Facility 2: c RW O +P O C U a) For additional faciliti- . ovide all same information on a sepa - - sheet. a „o, Are parkin. . -as to be used for detention? No Yes ma.'- Im depth due to required design storm? 1` Roadside Ditches: Will culverts serve access driveways at roadside ditches? No X Yes If"yes", provide information in next two boxes. Will 25-yr. flow pass without flowing over driveway in all cases? X Yes No Without causing flowing or standing water on public roadway? X Yes No Designs &materials comply with B-CS Technical Specifications? X Yes No Explain any"no" answers: .16 a■ vi• a) oAre culverts parallel to public roadway alignment? Yes X No Explain: U N N } X Creeks at Private Drives: Do private driveways, drives, or streets cross drainage i� o ways that serve Above-Project areas or are in public easements/ROW? m z X No Yes If"yes" provide information below. cn How many instances? Describe location and provide information below. ire > Location 1: 0 Location 2: Location 3: For each location enter value for: 1 2 3 w Design year passing without toping travelway? Water depth on travelway at 25-year flow? Water depth on travelway at 100-year flow? ,A. For more instances describe location and same information on separate sheet. STORMWATER DESIGN GUIDELINES Page 19 of 26 APPENDIX. D:TECH. DESIGN SUMMARY tut Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.11) Stormwater Management Concept (continued) Within Or Serving Subject Property(Phase, or Site)(continued) Named Regulatory Watercourses(&Tributaries): Are culverts proposed on these facilities? X No Yes,then provide full report documenting assumptions, criteria, analysis, computer programs, and study findings that support proposed design(s). Is report provided? Yes No If"no", explain: �, Arterial or Major Collector Streets: Will culverts serve these types of roadways? X No Yes How many instances? For each identify the CD location and provide the information below. } n Instance 1: gi Instance 2: x O Instance 3: c 0 O . Yes or No for the 100-year design flow: 1 2 3 ZE o Headwater WSE 1 foot below lowest curb top? c a) Spread of headwater within ROW or easement? w Is velocity limited per conditions(Table C-11)? • mExplain any"no"answer(s): • c ,O C6• U • O o 42 Minor Collector or Local Streets: Will culverts serve these types of streets? o n No X Yes How many instances? 2 for each identify the -o location and provide the information below: CD_ Q Instance 1: Culvert #1 on Chaco Canyon Drive co73 • c Instance 2: Culvert #2 on Halona Court CI3• o Instance 3: 2 c For each instance enter value, or"yes"/"no"for 1 2 3 U Design yr. headwater WSE 1 ft. below curb top? Yes Yes1111 < .a) 100-yr. max. depth at street crown 2 feet or less? Yes Yes E Product of velocity(fs)&depth at crown (ft)_? 0 0 Is velocity limited per conditions(Table C-11)? Yes Yes Limit of down stream analysis (feet)? 50' 50' Explain any"no"answers: Ip STORMWATER DESIGN GUIDELINES Page 20 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 ik SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY IPart 4— Drainage Concept and Design Parameters Continued (Page 4.12) Stormwater Management Concept (continued) I Within Or Serving Subject Property(Phase, or Site) (continued) All Proposed Culverts: For all proposed culvert facilities (except driveway/roadside ditch intersects) provide information requested in next eight boxes. I Do culverts and travelways intersect at 90 degrees? X Yes No If not, identify location(s)and intersect angle(s), and justify the design(s): Does drainage way alignment change within or near limits of culvert and surfaced approaches thereto? X No Yes If"yes" identify location(s), describe change(s), and justification: IAre flumes or conduit to discharge into culvert barrel(s)? X No Yes If yes, identify location(s)and provide justification: Are flumes or conduit to discharge into or near surfaced approaches to culvert ends? X No Yes If"yes" identify location(s), describe outfall design treatment(s): E a)a) c C O 0 Is scour/erosion protection provided to ensure long term stability of culvert structural 0 components, and surfacing at culvert ends? X Yes No If"no" Identify Ilocations and provide justification(s): I Will 100-yr flow and spread of backwater be fully contained in street ROW, and/or drainage easements/ROW? X Yes No if not,why not? I Do appreciable hydraulic effects of any culvert extend downstream or upstream to neighboring land(s) not encompassed in subject property? X No Yes If "yes"describe location(s)and mitigation measures: I Are all culvert designs and materials in compliance with B-CS Tech. Specifications? X Yes No If not, explain in Special Design Section of this Part. I STORMWATER DESIGN GUIDELINES Page 21 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 OM SECTION IX "" APPENDIX D - TECHNICAL DESIGN SUMMARY IMP Part 4— Drainage Concept and Design Parameters Continued (Page 4.13) Stormwater Management Concept (continued) Within Or Serving Subject Property(Phase, or Site) (continued) at . bridge included in plans for subject property project? No Yes mm If"ye-" .rovide the following information. Name(s)a 4 functional classification of the roadway(s)? OIR What drainage way(s)is to be , sed? r m — .411116. r A full report supporting al .spects of the proposed bridge(s tructural, geotechnical, hydrologic, and hydr.. is factors)must accompany this summa eport. Is the report U provided? es No If"no"explain: NIP Is a Stormwater Provide a general description of planned techniques: Pollution Prevention Hay Bale Barriers and Rock Dams will serve as the m Plan (SW3P) 1 z main protection against stormwater pollution. The c� established for `di project construction? Contractor shall use any other means necessary m throughout construction. _ No X Yes In vou Special Designs–Non-Traditional Methods Are any non-traditional methods (aquatic echosystems, wetland-type detention, natural stream IIIP replication, BMPs for water quality, etc.) proposed for any aspect of subject property project? X No Yes If"yes" list general type and location below. "' war mm • • - full report about the proposed special design(s) including rationale for use and expected be - ' Report must substantiate that stormwater management ••'- es will not be compromised, an. . ••-intenance cost will not exceed thos- , ..itional design solution(s). Is report provided? Yes • no" explain: XS STORMWATER DESIGN GUIDELINES Page 22 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 .r ens SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.14) Stormwater Management Concept(continued) Within Or Serving Subject Property(Phase, or Site) (continued) ^ •ecial Designs—Deviation From B-CS Technical Specifications If a design(s) or material(s) of traditional runoff-handling facilities deviate from provisions of B-CS -chnical Specifications, check type facility(ies) and explain by specific detail eleme . De = tion elements Drain system elements Channel features Culve eatures Swales Ditches Inlets * tfalls » Valley gu = s Bridges (explain in bridge report) In table below briefly i.-ntify specific element,justification for deviation(s). Specific Detail Eleme Justification for Deviation (attach add' '•nal sheets if needed) 1) Ow �,. 2) am 3) 111,11 4) 5) ow ,• Have elements been co. :inated with the City Engineer or her/his des ee? For each item above provide"yes" • no", action date, and staff name: 1) 2) Mao3) 4) Design Parameters Hydrology Is a map(s) showing all Design Drainage Areas provided? X Yes No Briefly summarize the range of applications made of the Rational Formula: For the Rational Formula we assumed residential areas had a WOO runoff coefficient of 0.5 for large residential or estate lots. What is the size and location of largest Design Drainage Area to which the Rational Formula has been applied? 4.00 acres Location (or identifier): Ditch Line Culvert #1 abg STORMWATER DESIGN GUIDELINES Page 23 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.15) Design Parameters (continued) •� Hydrology(continued) In making determinations for time of concentration, was segment analysis used? .r X No Yes In approximately what percent of Design Drainage Areas? As to intensity-duration-frequency and rain depth criteria for determining runoff flows, were any il�e criteria other than those provided in these Guidelines used? X No Yes If"yes" identify type of data, source(s), and where applied: IPP Ws For each of the stormwater management features listed below identify the storm return frequencies (year) analyzed (or checked), and that used as the basis for design. Feature Analysis Year(s) Design Year Stor s stem for arterial and collector streets Storm drain system for ets Open channels .r Swale/buried conduit co.. on in lieu of channel 10 Swa Roadside ditches and culverts serving them 2,5,10,25,50,100 25 & 100 OP De f`ies: spillway crest and its outfall Detention facilities: •. - and conveyance structure(s) Detention facilities: volume when ou - • ••ed VS Culverts serving private drives or str-- - Culverts serving pu• '. •-•ways Bri•�--. provide in bridge report. Hydraulics What is the range of design flow velocities as outlined below? Design flow velocities; 25 year Gutters Conduit Culverts Swales Channels Highest(feet per second) 10.50 Lowest(feet per second) 7.81 Streets and Storm Drain Systems Provide the summary information outlined below: Roughness coefficients used: For street gutters: NA For conduit type(s) RCP 0.014 Coefficients: WS STORMWATER DESIGN GUIDELINES Page 24 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX k APPENDIX D - TECHNICAL DESIGN SUMMARY Part 4— Drainage Concept and Design Parameters Continued (Page 4.16) Design Parameters(continued) r Hydraulics (continued) L - eet and Storm Drain Systems (continued) For th- ollowing, are assumptions other than allowable per Guidelines? Ei Inlet coe I .-nts? No Yes Head and friction losses No Yes Explain any"y- "answer: In conduit is velocity general v ' creased in the downstream dire on? Yes No Are elevation drops provided at in : s, manholes, and juncti. boxes? Yes No IExplain any"no" answers: I Are hydraulic grade lines calculated and own for .-,ign storm? Yes No For 100-year flow conditions? es No •lain any"no"answers: What tailwater conditi. s were assumed at outfall point(s)of the storm . .in system? Identify tin and - plain: each location I [ li i Open Channels If a HEC analysis is utilized, does it follow Sec VI.F.5.a? Yes No Outside of straight sections, is flow regime within limits of sub-critical flow? X Yes No If"no" list locations and explain: Culverts If plan sheets do not provide the following for each culvert, describe it here. NOIR For each design discharge, will operation be outlet(barrel)control or inlet control? 1400 All culverts will be inlet controlled. ! L Entrance,friction and exit losses: A 0.5 entrance and exit loss coefficients are used for sloped end treatments and square edged headwalls with wingwalls. Bridges Provide all in bridge report 1111mo 1 I STORMWATER DESIGN GUIDELINES Page 25 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY P Part 4— Drainage Concept and Design Parameters Continued (Page 4.17) ow Design Parameters(continued) Cornputer Software What computer software has been used in the analysis and assessment of stormwater management needs and/or the development of facility designs proposed for subject property project? List them below, being sure to identify the software name and version, the date of the OP version, any applicable patches and the publisher Open Office Calculator Spreadsheet r.YY NO 108 Part 5— Plans and Specifications OP Requirements for submittal of construction drawings and specifications do not differ due to use of a Technical Design Summary Report. See Section Ill, Paragraph C3. OP Part 6 — Conclusions and Attestation Conclusions Add any concluding information here: PP The Indian Lakes Subdivision, Phase 19 will have no adverse impact to downstream OP properties and conforms to the overall subdivision report. I Attestation Provide attestation to the accuracy and completeness of the foregoing 6 Parts of this Technical Design Summary Drainage Report by signing and sealing below. wro "This report(plan) for the drainage design of the development named in Part B was prepared OP by me (or under my supervision) in accordance with provisions of the Bryan/College Station Unified Drainage Design Guidelines for the owners of the property. All licenses and permits sm required by any and all state and federal regulatory agencies for the proposed drainage improvements have been issued or fall under applicable general permits." (Affix Seal) .,�• •��DF T .,- L. Iz8iC/¢ .•* 1*t Lice'.e.•.fessional Engineer 0* ' * 0 'JEFFERY L. ROBERTSON State of Texas PE No. g117115 1 9 4 7 4 5 • i O• lisCNS :`t„<.- 3 ‘„poNAto STORMWATER DESIGN GUIDELINES Page 26 of 26 APPENDIX. D:TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 _ 4111 1 1 1 1 1 i 1 1 EXHIBIT B Drainage Area Map i i 1 1 1 i 1 IDrainage Report Indian Lakes, Phase 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 EXHIBIT C- 1 Rational Method Calculations I II I r Drainage Report Indian Lakes, Phase 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 mo OOIDNr `nrn (D ri of o U r r CD M l() N 6) � N N Q) 001.15 N rn 6) r � r r ) N r M w r CO U)r CD CO (U U r C) CO CD M 0912rcoroo C r - Lc''), V r CD y V N- N- SVD O � r M U r co N O co l-- i CO N N SUIS C) r C - r O M V 04DOC° No C) N (D N U r r O M M N 0615C) (DCDCD 19 - CO N CO N 90 42 cc; xi O r m r w- N U 'N. CD (C) M 0 r In LC) r 91 _N c co p 00 00 ZO (DDivC (6 U rn M O CO N (6 V M LC) V O 2 VIS (DS v (6 Q (6 = L O LO CD 0,a 313SflE666T m .z £ r CC) CD CCS o1'o1e0. a m D X O J M Cr) C W � C Al-10013A E w O CD N- M 11 d co NI; LL MOld 21311f1O co M M HIE N31 (C of C N as MOld21311f1J . vena llVd�asNI- co co � MOld ONV12i3A0 f r r M CO CO O H10N31 co 0 0 MO-1J ONV113A0 ° n r CC (O O CO CD o O o v V0 1V101 O) 0 0 0 0 o p O O o 1N3IN2AVd o 0 0 0 Nn O O (D N 1VIIN301S321 N V N V321V00000 0 o O 03dO13A30Nf1 0 0 0 0 O O O N r o r O V321V1VIO1V N <} N N V321V 39VNIV210 O o 0 0 0 ZrNc+iv L 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 EXHIBIT C-2 Culvert Sizing Calculations I 1 1 1 I ' Drainage Report Indian Lakes, Phase 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 a a Z H W p .CO N CO O CO 7-1 / — \ Ic") V co 4..6 J O O N )O W N 6 T Q) O O I o I II N 15_ Ao Q wa) a) a) CD m o I I C oo u o c c c c c ,.... o I I HN. CT) N O N I Il E -'5'LO `O > N 'cr.); `cc.); N O N I I Q] O U > W co co co co N N N co N a u', N M O 1 > • a Q r^, O L CI N. O u) n . O _ I I v civ) =--- wmmmmm E N N N N N I I N y 1 n 1 oO -o a r o LO n )O N. r) C y- (/) O h• O = C lO 1- Cr) N N---01 C i —V 0 0 0 0 .- C J I 1 asL 1 Uo TO_ a) r o 1 O 0 0 0 3 z x w 0 c. Lo co co 03 4 ► O L 0 O (O r n 0 W /If Z / 0 F._. R- 0 N { Q) 0 < 0 0 CO0 (00 coo n co Y J O N CC J a e - `- '- e- Q 1 (/J O o w a O 0 0 � C) to } () I O = co FF a N ,- ,- Ru', N -, Cr' N U Q ~ Q �j p N Q CO 0) 0) O O - I- a 0 O = H O O O . .- _ re t o >< wa w > NC N. (D N O N Y > m r .DO L an CO a7 O N J N N N Com) C) 0 J O J _ ) W NNNNN000000 C -J C0 O Ci C a) UJ Z > N CO N. C) N. j �!r 0 0 > m m O N 0 g N 0 2 r - ,,i N N W }- Ill J z rw r 0 V co V > > 4F O CU CD O N . O = O 0 ,- W VO L N I' )O N ° C O E d o m CO (P O 7 O O c O O O r Z o o LO LO Ln O a) O L 0 N CO CO V )O Z a 0 Qa c c U 0 O 47 N O m fa 7 O" Q.N O V me' u-i O O a U ,- N V CO O a,, U I U CCC C .N N3 N O V 0, O) T O7 CD V Ch .N 2 O i O ,- f V 6 CO a) c O Q to 1> U d o >' 22C) ° N S O M N3 0 (n U 0 U o c aoCD CD a) L > w ?,- d > U a) c, m @ a c IT am a) N N J > N Z. � o o ' O 0 0 0 U 1 1 i 1 1 1 1 1 1 1 1 1 1 PM it 11011. Z H W p —Ln N N NICO lie • ,O N N .- 7 O O 4-0 4 .1 N W / LL Of \ i�/ y IN 'U .- O CO CO CO 0 d W c? (O o I I C O N Q,t .. p) N U) ) N 4-. I I 6 > O p C C C C C o U ea g I I H V OJ - O I gO _- O O` > . O O O N ?� V O C >> _ 6 (C u9 u9 N CI I ill m > v O U w co co co 00 co N N N C 15 I I `° I d C co (n (n y r I j Y a Q O L (D N- CO O) O I I G = du) —� Wcoco00coco ta) N N N N N I I 3, .- CD I [a I p cl 70 Q-O (h r- N O) (D 0. N Co O O = N N C] IF-,rI C • ( ..V O O O O O C J I I .= U O w a o v oo 0 O CC 3 a z Z CO 0 O Ln o CO N 10- ULvv �n (n )n H Z O J ' = = c--‘-.i NY oo _, O *k t 1 O 0 U d co _1 a > Q N co - U 000 (n )n 0 cc -U o co -o -} FQ -- N J N H Z a= 0 <N 0 > N N N- W CO m I- w c) —6 = 0 0 0 0 0 _ CC L x w a w > 0 N .' _O o N Oco -. N Y> J(C (C (C LO (C c6 ooc00000 U J U J v`n w N co N N N J = 0 CKS CC '� O = C 11.1 ---,- , . . Z m 0) r > 0 = )n co m e r: O m N C W ill J J Z 'C W s.4. 5N co co co co -N ,0 0 0 0 0 W "a- c73 L - Q) cc I- r C O_ O_ o O i':=1 n O o 0 O O O O O Z `i) m 000 )n (n o Q� U r a co O) o o Z •61. c U 0 0 0 O C N d N co co r-- N O t° 0 3 a13`3wN- N- mrn = 7, 0 d (n CO l'.... CO Oi - U LC U p m T To 3 in co co f- N (o O O 01 n o m — N C g 11 6 O r O o) O Q NN O O m E 0 > U d v 0 > . O to 2 N F, O a O N U V o O 0 C O -- Oct 0_ o c O 0 U d V 2 t N N Cr N O -0 0 F O C o N U t N N C L N > > N U U o O U 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Woo- 41401, Oft EXHIBIT C-3 Ditch Capacity Calculations 411M- ISO Mita 44.0 Sims Drainage Report Indian Lakes, Phase 19 1 1 1 i 1 1 1 1 1 1 1 1 1 1 1 1 1 c 0 2� N. E 0X C w _ 'E 0.� �o > 0 e H a Lu U , p L mob > 2^-, Oz WA \ 0 2yam / 0 01Y \o.. a t ct FL, is a, o N CO Ce 4 O) m •II II ` . v J N I c0 , ■ of , 00 N 1co O I 0 v � a) o CI'E u in E 'L 0 ` mi z •< m r�i °'._ N p) N�0 in cd C II 0 lbCC) �a� IN -4 ri Qj v Qom= • N 1 II II I 10 is N a) M . WO cal • O v W Lk \moi �� a) = t k� 00 II t X +-' / ' to O Q U 00 •f ° 1- &.,'V. v II , pr O v v 46 ,i a 0 0 6 X W fes" 1 1 1 1 i 1 1 1 1 1 i 1 1 1 1 1 1 1 , - 4.--„ n�t 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1