The URL can be used to link to this page

Home My WebLink AboutDrainage ReportDRAINAGE REPORT FOR PEBBLE CREEK Phase 9I College Station, Texas FEBRUARY, 2010 MBESI# 1065 -0013 1008 Woodcreek Drive, Suite 103 • College Station, Texas 77845 (979) 693-3838 • Fax: (979) 693 -2554 McCLURE & BROWNE ENGINEERING /SURVEYING, INC. Pebble Creek, Phase 9I Stormwater Management Technical Design Summary Report MBESI #1065 -0013 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: Pebble Creek Development 4500 Pebble Creek Parkway College Station, TX 77845 979 - 690 -0992 Submittal Date: February, 2010 Section 2 — General Information: Pebble Creek 9I is a phase of the Pebble Creek master planned community to be constructed in south College Station. The total area of the development is approximately 14.32 acres with a total of 27 lots. The plan is based on the Preliminary Plat submitted February 8, 2010. Section 3 — Project Location: Pebble Creek 9I is located in south College Station near the intersection of St. Andrew's Drive and Birkdale Drive. The entire project site is located within the city limits of College Station. The entire site is located within the Alum Creek Drainage Basin. A portion of the site is shown to be within the 100 -year floodplain. (Fema Firm Map # 48041CO205 D, Feb. 9, 2000). Based on Table B -1, Appendix B of the Unified Stormwater Design Guidelines, Alum Creek from S.H. 6 downstream is not required to have detention for flood control. Section 4 — Hydrologic Characteristics: The project site is mostly dense trees and underbrush with the heaviest concentrations of vegetation being near the creeks. There is a well defined drainage swale that separates Phase 9G from 9H. This drainage swale conveys stormwater south to Alum Creek. There are no existing drainage easements or ROW on the property. With this development drainage easements will be provided along the paths of conveyance to the existing creek. Stormwater Management Technical Design Summary Report Page 1 of 2 Pebble Creek, Phase 9I Section 5 — Stormwater Management: As stated in Section 3, no detention will be provided for this project. Stormwater will be conveyed by curb and gutter to recessed inlets. The stormwater will be discharged directly into the existing drainage swale or Tributary AC -1 of Alum Creek. Proper end treatments and riprap stabilization will be used to prevent erosion. Section 6 — Coordination and Permitting_ No coordination or permitting is required for this development. Section 7 — Reference: Report Exhibit A Exhibit B Exhibit C -1 Exhibit C -2 Exhibit C -3 Exhibit C -4 Exhibit C -5 Technical Design Summary Report Fema Floodplain Map Excerpt Drainage Area Map (Storm Drain) Rational Formula Drainage Area Calculations Inlet Computations Pipe Size Calculations Hydraulic Grade Line — 10 -Year Storm Hydraulic Grade Line — 100 -Year Storm Stormwater Management Technical Design Summary Report Pebble Creek, Phase 9I JEFF • r c: i9• r t o . •. 11 ; �) � 70 0 RY L. ROBERTSON 94745 Page 2 of 2 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 proposed project phases. This paragraph should also include reference to STORMWATER DESIGN GUIDELINES Page 1 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2008 SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY applications that are in process with either City: plat(s), site plans, zoning requests, 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 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 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 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: "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." STORMWATER DESIGN GUIDELINES Page 2 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2008 Part 2 — Project Administration Start (Page 2.1) Engineering and Design Professionals Information Engineering Firm Name and Address: McClure & Browne Engineering /Surveying, Inc. 1008 Woodcreek Dr., Ste. 103 College Station, Tx 77845 Jurisdiction City: Bryan X College Station Date of Submittal: Feb. 2010 Lead Engineer's Name and Contact Info.(phone, e-mail, fax): Jeffery Robertson, PE, PH: 693 -3838, FX: 693 -2554, jeffr @mcclurebrowne.com I Other: Supporting Engineering / Consulting Firm(s): Other contacts Developer / Owner / Applicant Information Developer / Applicant Name and Address: Pebble Creek Development 4500 Pebble Creek Pkwy., C.S., Tx 77845 Phone and e-mail: PH: 690 -0992 wendy_s @pebblecreek.org Property Owner(s) if not Developer / Applicant (& address): Phone and e-mail: Project Identification Development Name: Pebble Creek Subdivision Is subject property a site project, a single -phase subdivision, or part of a multi -phase subdivision? Multi -Phase If multi - phase, subject property is phase 91 of . Legal description of subject property (phase) or Project Area: (see Section II, Paragraph B -3a) See Final Plat 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. All phases are final platted. Phase 9C is currently under construction. General Location of Project Area, or subject property (phase): Part of Pebble Creek Subdivision in South College Station. Phase 91 is near the intersection of St. Andrew's Dr. and Congressional Drive. In City Limits? Bryan: acres. Extraterritorial Jurisdiction (acreage): Bryan: College Station: College Station: 14.32 acres. Acreage Outside ETJ: SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 3 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 2 — Project Administration Continued (page 2.2) Project Identification (continued) Roadways abutting or within Project Area or subject property: St. Andrew's Drive Congressional Drive Abutting tracts, platted land, or built developments: Phase 8 and 9 of Pebble Creek Undeveloped land to the south and west. Named Regulatory Watercourse(s) & Watershed(s): Trib. AC -1 of Alum Creek Tributary Basin(s): Plat Information For Project or Subject Property (or Phase) Preliminary Plat File #:. Under Review Final Plat File #: Date: Name: Pebble Creek 91 ,I /p If two plats, second name: File #: Status: Date: Zoning Information For Project or Subject Property (or Phase) Zoning Type: R -1 Existing or Proposed? Case Code: Case Date Status: Existing Zoning Type: Existing or Proposed? Case Code: Case Date Status: Stormwater Management Planning For Project or Subject Property (or Phase) Planning Conference(s) & Date(s): Participants: Preliminary Report Required? Submittal Date Review Date Review Comments Addressed? Yes No In Writing? When? Compliance With Preliminary Drainage Report. Briefly describe (or attach documentation explaining) any deviation(s) from provisions of Preliminary Drainage Report, if any. SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Effective February 2007 Page 4 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 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 With Other Departments of Jurisdiction City (Bryan or College Station) Dept. Contact: Date: Subject: Coordination With Non jurisdiction City Needed? Yes No X Summarize need(s) & actions taken (include contacts & dates): Coordination with Brazos County Needed? Yes No X Summarize need(s) & actions taken (include contacts & dates): Coordination with TxDOT Needed? Yes No X Summarize need(s) & actions taken (include contacts & dates): Coordination with TAMUS Needed? Yes No X Summarize need(s) & actions taken (include contacts & dates): Permits For Project or Subject Property (or Phase) 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. Entity Permitted or Approved ? Status of Actions (include dates) US Army Crops of Engineers No X Yes US Environmental Protection Agency No X Yes Texas Commission on Environmental Quality NoX Yes Brazos River Authority NoX Yes SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 5 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 3 — Property Characteristics Start (Page 3.1) Nature and Scope of Proposed Work Existing: Land proposed for development currently used, including extent of impervious cover? Land is currently mesquite and oak covered pasture land. Site Development Project (select all applicable) Redevelopment of one platted lot, or two or more adjoining platted lots. Building on a single platted lot of undeveloped land. Building on two or more platted adjoining lots of undeveloped land. Building on a single lot, or adjoining lots, where proposed plat will not form a new street (but may include ROW dedication to existing streets). Other (explain): Subdivision Development Project Construction of streets and utilities to serve one or more platted Tots. Construction of streets and utilities to serve one or more proposed lots on lands represented by pending plats. Describe Nature and Size of Proposed Site protects: building use(s), approximate floor space, impervious cover ratio. Subdivisions: number of lots by general type of use, linear feet of streets and drainage easements or ROW. 27 Lots 1,998 LF of Streets Project 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 Is any part of subject property abutting a Named Regulatory Watercourse (Section II, Paragraph B1) or a tributary thereof? No Yes X Is any part of subject property in floodplain area of a FEMA - regulated watercourse? No Yes X Rate Map 48041 CO205C Encroachment(s) into Floodplain areas planned? No X Encroachment purpose(s): Building site(s) Road crossing(s) Utility crossing(s) Other (explain): Yes 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. SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 6 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 ep at Or 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? Yes X Reference the study (& date) here, and attach copy if not already in City files. Is the stormwater earlier study? management plan for the property in substantial Yes No If not, explain how conformance with the it differs. No If subject property plan for the is not part of multi -phase project, describe stormwater management 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? Describe them (include approximate size, volume, outfall, model, etc). X No Yes Any known drainage or flooding problems in areas near subject property? Identify: No Yes _X _ Based (see Table on location of B -1 in Appendix Detention is required. study property in a watershed, is Type 1 Detention (flood control) needed? B) Need must be evaluated. X Detention not required. If the need for Type 1 Detention must be evaluated: What decision has been reached? By whom? How was determination made? SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 7 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 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? describe splits below. In Part 4 describe design concept X No Yes If yes, for handling this. Watershed or Basin Larger acreage Lesser acreage Above - Project Areas(Section II, Paragraph B3 -a) Does Project Area (project or phase) receive runoff from upland areas? Size(s) of area(s) in acres: 1) _2.34 2) 3) No X Yes 4) Flow Characteristics (each instance) (overland sheet, shallow concentrated, recognizable Watercourse or tributary); concentrated section(s), small creek (non - regulatory), regulatory Overland Sheet flow from upstream lots. Flow determination: Outline hydrologic methods and assumptions: Does storm runoff drain from public easements or ROW No X Yes If yes, describe facilities in easement onto or across subject property? or ROW: the property. Stormwater from Congressional Court flows onto Are changes in runoff characteristics subject to change in future? Explain Conveyance Pathways (Section II, Paragraph C2) Must runoff from study property drain across lower properties before reaching a Regulatory Watercourse or tributary? X No Yes Describe length and characteristics of each conveyance pathway(s). Include ownership of property(ies). SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 8 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 3 — Property Characteristics Continued (Page 3.4) Hydrologic Attributes of Subject Property (or Phase) (continued) Conveyance Pathways (continued) Do drainage easements exist for part of pathway(s)? No any If yes, for what part of length? % Created by? plat, or instrument. If instrument(s), describe their provisions. Yes Pathway Areas Where runoff must cross lower properties, describe characteristics of abutting lower property(ies). (Existing watercourses? Easement or Consent aquired ?) Nearby Drainage Facilities Describe any built or improved drainage facilities existing near the property (culverts, bridges, lined channels, buried conduit, swales, detention ponds, etc). Culvert @ St. Andrews Drive. Do any of design? these have hydrologic or hydraulic influence on _X No Yes If yes, explain: proposed stormwater _ SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 9 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Start (Page 4.1) Stormwater Management Concept 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. The upland flow is from residential Tots so no design features will be required. Discharge(s) To Lower Property(ies) (Section II, Paragraph El) Does project include drainage features (existing or future) proposed to become public via platting? No X Yes Separate Instrument? No Yes Per Guidelines reference above, how will runoff be discharged to neighboring property(ies)? Establishing Easements (Scenario 1) Release (Scenario 2) of the two Scenarios Pre - development Combination Scenario 1: If easements are proposed, describe where needed, and provide status of actions on each. (Attached Exhibit # ) Scenario 2: Provide general description of how release(s) will be managed etc.). (Attached to pre - development Exhibit # ) conditions (detention, sheet flow, partially concentrated, Combination: If combination is proposed, explain how discharge will differ from pre - each area (or point) of release. development conditions at the property line for If Scenario 2, or Combination are to be used, has proposed design No Yes Explain been coordinated with and provide owner(s) of receiving property(ies)? documentation. SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Effective February 2007 Page 10 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 MR OM ■s ■r Part 4 — Drainage Concept and Design Parameters Continued (Page 4.2) Stormwater Management Concept (continued) Within Project Area Of Multi -Phase Project Will project result in shifting runoff between Basins or between Watersheds? X No Identify gaining Basins or Watersheds and acres shifting: What design and mitigation is used to compensate for increased runoff from gaining basin or watershed? Yes How will runoff from Project Area be mitigated to pre- development conditions? Select any or all of 1, 2, and /or 3, and explain below. 1. With facility(ies) involving other development projects. 2 Establishing features to serve overall Project Area. 3. On phase (or site) project basis within Project Area. 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) project: 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)? Are other Best Management Practices for reducing stormwater pollutants proposed? No Yes Summarize type of BMP and extent of use: If design of any runoff - handling facilities deviate from provisions of B -CS Technical 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 SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 11 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 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 Yes Identify type and _X _ general size and In which phase(s). 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): Within Or Serving Subject Property (Phase, or Site) If property part of larger Projerf Area, is design in substantial conformance with earlier analysis and report for larger area? X Yes No, then summarize the difference(s): Identify whether each of the types of drainage features listed below are included, extent of use, and general characteristics. Typical shape? Surfaces? ditches use Yes Steepest side slopes: Usual front s opes: Usual back slopes: Flow line slopes: least Typica distance from travelway: (Attached Exhibit # ) typical greatest Are longitudinal culvert ends in compliance with B -CS Standard Specifications? Yes No, then explain: At intersections or otherwise, do valley gutters cross arterial or collector streets? No Yes If yes explain: pets with cu )utter Wised Jo X _X Are valley gutters proposed to cross any street away from an intersection? No Yes Explain: (number of locations ?) _X — SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Effective February 2007 Page 12 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.4) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Are streets with curb and gutter used? (continued) Gutter line slopes: Least Usual Greatest _3.39% . _0.60% Are inlets recessed on arterial and collector streets? X Yes No If "no ", identify where and why. Will inlets capture 10 -year design stormflow to prevent flooding of intersections (arterial with arterial or collector)? X Yes No If no, explain where and why not. Will inlet size and placement prevent exceeding allowable water spread for 10 -year design storm throughout site (or phase)? Yes No If no, explain. _X _ Sag curves: Are inlets placed at low points? X Yes No Are inlets and conduit sized to prevent 100 -year stormflow from ponding at greater than 24 inches? X Yes No Explain "no" answers. Will 100 -yr stormflow be contained in combination of ROW and buried conduit on whole length of all streets? X Yes No If no, describe where and why. Do designs for curb, gutter, and inlets comply with B -CS Technical Specifications? X Yes No If not, describe difference(s) and attach justification. — — Is storm drain system used? No >< Yes Are any 12 -inch laterals used? X No Yes Identify length(s) and where used. Pipe runs between system access points (feet): Typical 100' _Longest 260' Are junction boxes used at each bend? X Yes No If not, explain where and why. Are downstream soffits at or below upstream soffits? Yes X No If not, explain where and why: Least amount that hydraulic grade line is below gutter line (system- wide): 1.06' SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 13 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.5) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Storm drain system (continued) (on separate sheet provide same info. for more instances) (s)Ileiin0 Describe watercourse(s), or system(s) receiving system discharge(s) below (include design discharge velocity, and angle between converging flow lines). 1) Watercourse (or system), velocity, and angle? Storm Drain 1, 3.5 fps, 30 deg. 2) Watercourse (or system), velocity, and angle? Storm Drain 2, 5.8 fps, 30 deg. 3) Watercourse (or system), velocity, and angle? Storm Drain 3, 4.3 fps, 90 deg. For each outfall above, what measures are taken to prevent erosion or scour of receiving and all facilities at juncture? 1) Rock Rip -Rap 2) Rock Rip -Rap 3) Rock Rip -Rap Are swales used to drain streets? X No Yes 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): Flow line slopes (minimum and maximum): Outfall characteristics for each (velocity, convergent angle, & end treatment). Will 100 -year design storm runoff be contained within easement(s) or platted drainage ROW in all instances? Yes No If "no" explain: SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 14 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 w,1 s.o Ow SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 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? X No Yes If so, provide the following: a) Is 25 -year flow contained with 6 inches of freeboard throughout ? Yes No 0 Are top of banks separated from road shoulders 2 feet or more? Yes No E Are all ditch sections trapezoidal and at least 1.5 feet deep? Yes No a) as 0 w a) a) U c o o Z cn XI 0 c c as c a ca c as U L c .- a) c o o f6 E o c c — a� E a� as = N c o '> 0 • L E o - U m L C as o n. o a) N m c � o m For any "no" answers provide location(s) and explain: 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: Space for 100 -year storm flow? ROW Easement Width Swale Surface type, minimum and maximum slopes: Conduit Type and size, minimum and maximum slopes, design storm: Inlets Describe how conduit is loaded (from streets /storm drains, inlets by type): Access Describe how maintenance access is provided (to swale, into conduit): Instance 2 Describe general location, approximate length: Is 100 -year design flow contained in conduit/swale combination? Yes No If "no" explain: Space for 100 -year storm flow? ROW Easement Width Swale Surface type, minimum and maximum slopes: Conduit Type and size, minimum and maximum slopes, design storm: Inlets Describe how conduit is loaded (from streets /storm drains, inlets by type): Access Describe how maintenance access is provided (to swale, into conduit): Page 15 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.7) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Will swales without buried conduit receive runoff from public ROW or easements? X No Yes. Explain If "yes" provide the following information for each instance: Instance 1 Describe general location, approximate length, surfacing: Is 100 -year design flow contained in swale? Yes No Is swale wholly within drainage ROW? Yes No Explain "no" answers: Access Describe how maintenance access is provide: Instance 2 Describe general location, approximate length, surfacing: Is 100 -year design flow contained in swale? Yes No Is swale wholly within drainage ROW? Yes No Explain "no" answers: Access Describe how maintenance access is provided: Instance 3, 4, etc. If swales are used in more than two instances, attach sheet providing all above information for each instance. Channel improvements proposed? X No Yes Explain "New" channels: Will any area(s) of concentrated flow be channelized (deepened, widened, or straightened) or otherwise altered? No Yes If only slightly shaped, see "Swales" in this Part. If creating side banks, provide information below. Will design replicate natural channel? Yes No If "no ", for each instance describe section shape & area, flow line slope (min. & max.), surfaces, and 100 -year design flow, and amount of freeboard: Instance 1: Instance 2: Instance 3: SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Effective February 2007 Page 16 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.8) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Channel Improvements (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.), surfaces, and 100 -year design flow. Watercourses (and tributaries): Aside from fringe changes, are Regulatory Explain below. Watercourses proposed to be altered? No Yes Submit full report describing proposed changes to Regulatory existing and proposed section size and shape, surfaces, alignment, length affected, and capacity, and provide full documentation of and data. Is full report submitted? Yes No Watercourses. Address flow line changes, analysis procedures If "no" explain: All Proposed Channel Work: For all proposed channel work, provide information requested in next three boxes. 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: Are ROW / easements sized to contain channel and required Yes No If not, identify location(s) and explain: maintenance space? SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 17 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.9) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) How many facilities for subject property project? For each provide info. below. For each dry-type facilitiy: Faci ity 1 Faci ity 2 Acres served & design volume + 10% 100 -yr volume: free flow & plugged Design discharge (10 yr & 25 yr) Spillway crest at 100 -yr WSE? Berms 6 inches above plugged WSE? Explain any "no" answers: yes no yes no yes no yes no For each facility what is 25 -yr design Q, and design of outlet structure? Facility 1: Facility 2: Do outlets and spillways discharge into a public facility in easement or ROW? Facility 1: Yes No Facility 2: Yes No If "no" explain: For each, what is velocity of 25 -yr design discharge at outlet? & at spillway? Facility 1: & Facility 2: & Are energy dissipation measures used? No Yes Describe type and location: For each, is spillway surface treatment other than concrete? Yes or no, and describe: Facility 1: Facility 2: For each, what measures are taken to prevent erosion or scour at receiving facility? Facility 1: Facility 2: If berms are used give heights, slopes and surface treatments of sides. Facility 1: Facility 2: SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 18 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 RIP NW OW Part 4 — Drainage Concept and Design Parameters Continued (Page 4.10) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Detention Facilities (continued) Do structures comply with B -CS Specifications? Yes or no, and explain if "no ": Facility 1; Facility 2: For 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? Are culverts used at private crossings? X No Yes Roadside Ditches: Will culverts serve access driveways at roadside ditches? No Yes If "yes", provide information in next two boxes. Will 25 -yr. flow pass without flowing over driveway in all cases? Yes No Without causing flowing or standing water on public roadway? Yes No Designs & materials comply with B -CS Technical Specifications? Yes No Explain any "no" answers: Are culverts parallel to public roadway alignment? Yes No Explain: Creeks at Private Drives: Do private driveways, drives, or streets cross drainage ways that serve Above - Project areas or are in public easements/ ROW? No Yes If "yes" provide information below. How many instances? Describe location and provide information below. Location 1: Location 2: 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? For more instances describe location and same information on separate sheet. SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 19 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.11) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) (for more instances of any type describe location and same information on separate sheet) Named Regulatory Watercourses (& Tributaries): Are culverts proposed on these assumptions, support proposed ", explain: facilities? No Yes, then provide full report documenting that If "no criteria, analysis, computer programs, and study findings design(s). Is report provided? Yes No Arterial or Major Collector Streets: Will culverts serve these types of roadways? For each identify the No Yes How many instances? location and provide the information below. Instance 1: Instance 2: Instance 3: Yes or No for the 100 -year design flow: 1 2 3 Headwater WSE 1 foot below lowest curb top? Spread of headwater within ROW or easement? Is velocity limited per conditions (Table C -11)? Explain any "no" answer(s): Minor Collector or Local Streets: Will culverts serve these types for of streets? each identify the No Yes How many instances? location and provide the information below: Instance 1: Instance 2: Instance 3: For each instance enter value, or "yes" / "no" for: 1 2 3 Design yr. headwater WSE 1 ft. below curb top? 100 -yr, max. depth at street crown 2 feet or less? Product of velocity (fps) & depth at crown (ft) _ ? Is velocity limited per conditions (Table C -11)? Limit of down stream analysis (feet)? Explain any "no" answers: SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 20 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.12) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) Culverts (continued) All Proposed Culverts: For all proposed culvert facilities (except driveway /roadside boxes. ditch intersects) provide information requested in next eight Do culverts and travelways intersect at 90 degrees? 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 approaches thereto? No Yes If "yes" identify location(s), culvert and surfaced describe change(s), and justification: Are flumes or conduit to discharge into culvert barrel(s)? No Yes If yes, identify location(s) and provide justification: . Are flumes or conduit to discharge into or near surfaced approaches No Yes If "yes" identify location(s), describe outfall to culvert ends? design treatment(s): Is scour /erosion protection provided to ensure long term stability of culvert structural components, and surfacing at culvert ends? Yes No If "no" Identify locations and provide justification(s): Will 100 -yr flow and spread of backwater be fully contained in drainage easements/ ROW? Yes No if not, why street ROW, and /or not? Do appreciable hydraulic effects of any culvert extend downstream or upstream to neighboring land(s) not encompassed in subject property? No Yes If "yes" describe location(s) and mitigation measures: Are all culvert designs and materials in compliance with B -CS Yes No If not, explain in Special Design Section Tech. Specifications? of this Part. SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 21 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.13) Stormwater Management Concept (continued) Within Or Serving Subject Property (Phase, or Site) (continued) a> a m Is a bridge included in plans If "yes" provide the following for subject property project? X No Yes information. Name(s) and functional classification of the roadway(s)? What drainage way(s) is to be crossed? A full report supporting all aspects of the proposed bridge(s) hydrologic, and hydraulic factors) must accompany this summary provided? Yes No If "no" explain: (structural, geotechnical, report. Is the report > .i c3 Q, m Is a Stormwater Pollution Prevention Plan (SW3P) established for project construction? No X Yes Provide a general description of planned techniques: Silt Fence Inlet Protection Construction Exit Special Designs — Non - Traditional Methods Are any non - traditional methods replication, BMPs for water quality, X No Yes If "yes" list (aquatic echosystems, wetland -type detention, natural stream etc.) proposed for any aspect of subject property project? general type and location below. Provide full report about the proposed expected benefits. Report must be compromised, and that maintenance solution(s). Is report provided? special design(s) including rationale substantiate that stormwater management cost will not exceed those of Yes No If "no" explain: for use and objectives will not traditional design SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 22 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 s Part 4 — Drainage Concept and Design Parameters Continued (Page 4.14) 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 B -CS Technical Specifications, check type facility(ies) and explain by Detention elements Drain system elements from provisions of specific detail element. Channel features Inlets Outfalls Culvert features Swales Ditches 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) 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 Is a map(s) showing all Design Drainage Areas provided? X Yes No Briefly summarize the range of applications made of the Rational Formula: Determination of flow rates for inlets and pipes along the roadway. What is the size and location of largest Design Drainage Area to which the Rational Formula has been applied? 1.76 _ acres Location (or identifier): Drainage Area 4 SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 23 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 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? X No Yes In approximately what percent of Design Drainage Areas? % _ As to intensity- duration- frequency and rain depth criteria for determining runoff flo :, were any criteria other than those provided in these Guidelines used? No Y-: If "yes" _X identify type of data, source(s), and where applied: For each of the stormwater management features listed lo id t t storm return frequencies (year) analyzed (or checked), and at used a- th is for design. Feature /�. alysis Year(s) Design Year Storm drain system for arterial and collector r. ��/ a 0 yr 10, 100 Storm drain system for local streets C 1 0 yr 10, 100 Open channels 1 1 N/A N/A Swale /buried conduit combinatio ; - • • . -I N/A N/A Swales N/A N/A Roadside ditches an culv art ► the N/A N/A Detention facilities: spit and its outfall N/A N/A Detention facilities: outlet a : conveyance structure(s) N/A N/A Detention facilities: volu when outlet plugged N/A N/A Culverts serving privat drives or streets N/A N/A Culverts serving pu% is roadways N/A N/A Bridges: provid= in bridge report. N/A N/A Hydraulics What is th: range of design flow velocities as outlined below? Design .w velocities; Gutters Conduit Culverts Swales Channels ghest (feet per second) 1.07 6.3 Lowest (feet per second) 0.20 3.1 - treets and Storm Drain Systems Provide the summary information outlined below: Roughness coefficients used: For street gutters: 0.014 For conduit type(s) RCP HDPE Coefficients: 0.014 0.014 SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D — TECHNICAL DESIGN SUMMARY Page 24 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 - Drainaae Concept and Design Parameters Continued (Page 4.15) Design Parameters (continued) Hydrology (continued) In making determloations for time of concentration, was segment analysis used? X No Yes In approximately what percent of Design Drainage Areas? % As to intensity - duration freg oency and rain depth criteria for criteria other than those provided in these Guidelines used? identify type of data, source(s), and where applied: . determining ( No runoff flows, Yes were any If "yes" 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 Storm drain system for arterial and collector streets 1 I D Storm drain system for local streets td I Open channels Swale/buried conduit combination in lieu of channel Swales Roadside ditches and culverts serving them Detention facilities: spillway crest and its outfall Detention facilities: outlet and conveyance structure(s) Detention facilities: volume when outlet plugged 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? Design flow velocities; Gutters Conduit Culverts Swales Channels Highest (feet per second) 1, 07 4, 3 Lowest (feet per second) t) . 2 3 . i Streets and Storm Drain Systems Provide the summary information outlined below: Roughness coefficients used: For street gutters: For conduit type(s) MEIN' RCS }Vt. 0.01 0.0 N D. 0iq _}t pc Coefficients: SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Page 24 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 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? X No Yes Head and friction losses X No Yes Explain any "yes" answer: In conduit is velocity generally increased in the downstream direction? Are elevation drops provided at inlets, manholes, and junction boxes? Explain any "no" answers: _ X _ Yes No X Yes No Are hydraulic grade lines calculated and shown for design storm? X Yes No For 100 -year flow conditions? X Yes No Explain any "no" answers: What tailwater conditions were assumed at outfall point(s) of the storm drain system? Identify each location and explain: Water Service Elevations from FEMA FIRM. 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 If "no" list locations and explain: flow? Yes No 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? Entrance, friction and exit losses: Bridges Provide all in bridge report SECTION IX STORMWATER DESIGN GUIDELINES Effective February 2007 APPENDIX D - TECHNICAL DESIGN SUMMARY Page 25 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Part 4 — Drainage Concept and Design Parameters Continued (Page 4.17) Design Parameters (continued) 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 Microsoft Excel Spreadsheet <(/ Part 5 — Plans and Specifications Requirements for submittal of construction dr.. . and cifications do not differ due to use of a Technical Design Summary Report. See ' io I, 'Kg" ph C3. Part 6 — Conclusions and Atte tati • n Co r�sions Add any concluding informatio V )/ Attestation Provide attestati n to the accuracy and completeness of the foregoing 6 Parts of this Technical Design Summ ry Drainage Report by signing and sealing below. "This repo plan) for the drainage design of the development named in by me (or under my supervision) in accordance with provisions of the Unified rainage Design Guidelines for the owners of the property. All requir d by any and all state and federal regulatory agencies for the impr vements have been issued or fall under applicable general permits." (Affix Seal) Part B was prepared Bryan /College Station licenses and permits proposed drainage Licensed Professional Engineer State of Texas PE No. SECTION IX APPENDIX D - TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Page 26 of 26 APPENDIX. D: TECH. DESIGN SUMMARY As Revised February 2008 Effective February 2007 op • VP Part 4 — Drainage Concept and Design Parameters Continued (Page 4.17) Design Parameters (continued) 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 Exce l Part 5 — Plans and Specifications Requirements for submittal of construction drawings and specifications do not differ due to use of a Technical Design Summary Report. See Section III, Paragraph C3. Part 6 — Conclusions and Attestation Conclusions Add any concluding information here: 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. This report (plan) for the drainage design of the development named in by me (or under my supervision) in accordance with provisions of the Unified Drainage Design Guidelines for the owners of the property. All required by any and all state and federal regulatory agencies for the improvements h. ve been issued or fall under applicable general permits 1 (Affix Seal) Part B was prepared Bryan/College Station licenses and permits proposed drainage ' � 1 * s ` i JEFFE - • -5: // 9 " I ', O.C.••. 1 E C 1` Y L. 94 Gin I is Licl i a rofes F. al Engineer q I I� (5 State of Texas PE No.' SECTION IX APPENDIX D — TECHNICAL DESIGN SUMMARY STORMWATER DESIGN GUIDELINES Page 26 of 26 APPENDIX. D: TECH. DESIGN SUMMARY Effective February 2007 As Revised February 2009 VV ROBERTSON i 745 .•' llt t � s / 0NA` s- • • • • 1 i t Pi? tF mininsii eammom Iiiiiiiiiiiiii mommunumumu Oiliiiiiiiinl "3013iiiiiiiiiin iiiiiiiiiiiiiii NOM IN3MAVd IMMO V3 1VICII IMO= !Militia H MO ONV iiiiiiiiiiiin INUENUEUEUU liiiiiiiiiiili Z19 31' 11V M011 21311(1 Hl'9N31 MOId 2!311(1 1lVd M01 1 ONV1213AO 1VI1N3OIS3 V321V O3d013A3ONf1 V321V 3OVNIVbIO O z ch w V) v) a z O N Q N o I- > m Xvm W ww J a Z V w J w 0. papinoad gaav paainbag eaav I'ldaa papuod papinoad •,I •pbag •Z •3•Z aad 'dVD z 0 laiui lg 183 .ox lalul gldaa alquMMolid glda nMol3 aallnD a do's laaalS glPMAA 0 lalul lu a lllo1 aaAO Laatj eaag avuteaa yaad alt ult'ua Atol'aaAO 'Old VP2iV aovK Wua ommummoom IMIESENCEIN INCESIMEMEN N N N N N N N N Q m T T O V1 r to V1 N N N .'.' CU 0 0 tll CL) N c cct - 3, goo a ww a ,a ° °a o, a � o .0 o 0 0 2_ a a - 0 b b b b CA tA 0 6) ti � y Q y y w y h y 4 C.) aa 00 .., N M 4 V-, 'D l- 00 (T y • .■i 0000 00000 00 00 00 vD 00 00 00 M M M M M M M M d M M M O O O O O O O O O O O O O ,o -r- --1 N M N O M d M M M M N 4 N O O O O o O O O o O O O O O O on , .p M l0 %.O ■.O V0 k.O VD ‘.D VD Q1 O, %.O O M O O O O- '. O O .-ti ~ O O O O O O O O N 00 00 000 00 00 V1 [" N kr, Vi O O O 0 0 0 0 0 0 0 00 0 0 0 0 O O O O O O O O N O O O O N •-� O N l Vl N trl N 0 n kfi O M Vl N V'1 N '-- cn O z c cd et c1 O 0 o O 0 cd c0 cd cd C Qm M LO CO N 00 O O T T EXHIBIT C -3 PIPE SIZE CALCULATIONS PEBBLE CREEK SUBDIVISION PHASE 9 -1 z z HI 1A 1B 2 3 4 5 6 7 8 9 20A 20B 21 F z 1B 2 3 4 5 HW5 7 8 9 HW9 20B 21 HW21 0 Ac. 0.9 1.5 1.5 1.8 2.8 3.5 0.9 1.5 1.9 2.0 0.9 1.3 1.3 co F min 10.0 10.0 10.3 10.6 11.3 11.4 10.0 10.2 10.3 10.5 10.0 10.0 11.0 2 yr 10 10 10 10 10 10 10 10 10 10 10 10 10 cfs 7.7 12.9 12.7 15.2 22.8 28.3 7.5 13.1 16.0 17.1 7.5 10.8 10.4 cfs 10.1 16.7 16.5 19.8 22.8 28.3 9.8 17.1 16.0 17.1 9.7 14.1 13.5 z 1 1 1 1 1 1 1 1 1 1 1 1 P•4 cfs 10.1 16.7 16.5 19.8 22.8 28.3 9.8 17.1 16.0 17.1 9.7 14.1 13.5 6.00 0.63 0.61 0.88 0.36 0.55 0.21 0.66 0.18 0.20 5.57 0.45 0.41 rf 1 1 13 24 24 24 30 30 24 24 30 30 13 24 24 fps 10.9 5.3 5.3 6.3 4.6 5.8 3.1 5.4 3.3 3.5 10.5 4.5 4.3 13 97 96 251 31 170 35 39 41 44 13 260 40 min 0.02 0.31 0.31 0.67 0.11 0.49 0.19 0.12 0.21 0.21 0.02 0.97 0.15 min 10.02 10.33 10.63 11.30 11.41 11.90 10.19 10.31 10.52 10.73 10.02 10.99 11.14 *Includes 33% Flow Increase for pipe sizes <27 dia. ** See Plan & Profile for pipe slope used (Pipe slope >or= Friction slope) 2/9/2010 10650013- DRAa.xls Exhibit C -3 176 OI(INI( 01 I m ^ m o Ro ca p LL 11 H1v 1m - 1T.1( 1 1 1 1 LL N �t o _L- N ° mc 1 �1 IIuNiml7l N 0 n u� o ` � i1 m1(01 n 1 r, P(I(gI(1 - �t Lt t- - r - ( 1 10 1 1010 1 0 0 1 01 0 0 01� 0100 0 O1O I�I��I 1 m(n -011 o1il� ~IC NN N N N N N N N N14-Alo C (/) Y %344' (m+ N1NIM L111 N N NININ N N N I= 010 01010101 010 0 15 a ( (010 dO� 1 d1 (01(011 VIVOIVI 11 o 5 ( 1 1 1 0 1 ) 1 01 CV 01 (0 • Oi ( >11 1 1 1 1 1 1 1 ▪ rn - 1N1w ,1! 0 01 1°1 j 0 0 04 0 0 0 0l� L 1 _ r r 1 I � a0 1I Din � l(0(0v ( ( Z 0 N N I NIN N N Ncsi N I I COI4 —NNr ��N O V "�' N N N N N l X1 fiL 1 - (( ,912 S.1%21 -I c� C ' 4 0I(( Z O J N NININ NI N� NN IT � e + 10 I \0a I le 1 �\ - v 1 j I1((0I)10m11 N Id (V 010 0 0 0 0 I' _ II 0 I LLB L 1 I�L T r 11 _ (II0- 01110(0 1 1110) 1 0 ( N � 1 �1� 010 1 010 1 1 0 1 01 0 0 ▪ I_ H 1 i l i 11 11 � (1 m 111 r I m 1 , r1oI �� 1 jN r l - a 1 l p - O(1c0)1N1N1('��+1 ( N ;i 1 H 1 + 4 4-HQ ol�1 o?m1T v,lw 10 NIPAI N H“, 1 010 C N y1cr � , 1 V ( L N N NIN _L fi I I�� I( J,3 NII ^1�01v01 N 011111°1 1�IM LL � N IN NIN LL =N 1( (1 I4 (01 1(1 01 010 N N N N N'NN N NIN r = 10I 0 2 Q(11r1 I I= ry cI- t 1 . 1 f - 1 1 IL 1 (I NII I 11 111 I 117 N1� E Out- 234.25 (241 E In- 233.72 (24') 0ut 233.22 (30') f- 233. E In- 233.12', (30') E. Out- 232.72 (30") E - 232.68 Sta. 11 +70.00, f- 232.81 Begin 30' 4:1 ',RCP S.E.T. E Out- 241.17 (241 f - 240.82 E.. 239.94 f -.. 238,81 .......... f- 238.48 } f- .. 234,24 . E - 239.14 E In- 237.77(24 ") Out- 237.27 (30') E In- 237.10 (30 ") E Out- 237.00 (301 f— 235.54 Sta. 16 +55.99, f - 232.78 Begin 30" 4:1 RCP S.E.T. E In- 240.43'.(24') Sta. 10 ".95 Const. ", Std Juno. Box Sta. 10 +00.00 Conet 10' Rec. Inlet 510. 10 +37.64 onet 10' Rec. Inlet 5ta. +:1.18 con. 5 121 ; Re c. Inlet 1 11 2 5. Conel 5' Re 0 - /1 . let . 10 +00.00 Conet. 10' Rec. Inlet Sta. 11 +99.58 Cones. 5' Rec. Inlet Sta. 14 +92.48 Cons 10' Rec. Inlet A 5 9 Project Name, Phase McCLURE & BROWNE ENGINEERING /SURVEYING, INC. Engineer Reg. No. F-458 • Survey Reg. No. 101033-00 1008 Woo0creek Dr.. Suite 103 College Station, Tx. 77845 • (979) 693-3838 1314 106 Suite 210 Huntsville, Tx. 77320 - (936) 294 -9749 R E V I S I O N S DRAWN 67: DRL, DRW DESIGNED 87: SCF CHECKED 87: ,0R M500 13 - 0(10 - 1401, DATE: APRIL 2010 > z ca 0 c 00 z O -1 0 Z O)) 005 N E Out= 232.90 (30") W 9 U Sto. 10 +00.00 �'. 1 Out- 236.63 (30") 1 - 236.11 1 — . 235,57 _. '.. 1- 235.02 1 _. 1 In= 233.83 (30") Sta. 12 +61.61 Cont. e, Std. Junc. Box Sta. 12 +91.42] 1- 232.58 Begin 24" 4:1 RCP S.E.T. a in / / / / ." �� , � 81 L R \ , J \ I N I I / / it . \ N. \ \\I I // a / A A ut 9 Project Name, Phase McCLURE & BROWNE ENGINEERING /SURVEYING, INC. Engineer Reg. No. F-458 - Survey Reg. No. 101033-00 1008 Woodcreek Dr., Suite 103 College Station, Tx. 77845 • (979) 693-3838 1314 1015 Street, Suite 210 Huntsville, Tx. 77320 - (936) 294 -9749 R E V I S I O N S DATE: APRIL 2010 DRAWN BY: DRL DRW DESIGNED BY: SCF CHECKED BY: JLR