Loading...
HomeMy WebLinkAboutResponse to staff commentsMay 3, 2010 Ms. Lauren Hovde Staff Planner Planning & Development Services City of College Station P.O. Box 9960 College Station, Texas 77842 Re.: Dear Ms. George: Below is the summary of the revisions made per staff's comments. PLANNING: ENGINEERING: COMMENT #1: ACTION: J COMMENT #2: McCLURE & BROWNE, ENGINEERING /SURVEYING, INC. 1008 Woodcreek Dr., Suite 103 College Station, Tx. 77845 • (979) 693 -3838 Engineer Reg. No. F -458 1314 10th Street, Suite 210 • Huntsville, Tx. 77320 • (936) 294 -9749 Survey Reg. No. 101033 -00 PEBBLE CREEK PH 91 (FP) — Final Plat/Engineering Plans Staff Review Response MBESI #: 1065 -0013 Please add a note stating the responsible entity for Common Area maintenance. See revised plat. Please add the zoning, average lot size, and acres of right -of -way dedication as a note on the Final Plat document. See revised plat. The acreage is slightly different from the preliminary plat. The numbers shown on the Final Plat are accurate with the actual final configuration of the lots and right -of -way. COMMENT #3: The Planning and Zoning Commission note has been removed. See revised plat. COMMENT #1: ACTION: COMMENT #2: ACTION: ACTION: ACTION: COMMENT #3: ACTION: Add a note to the plat regarding boring of utilities in floodway areas as was noted on Preliminary Plat. See revised plat. Revise Note 2 on Plat to indicate some of the property is located in floodplain area. See revised plat. Some of the PUEs in the common area are called out, but lines do not show up. See revised plat. 1 Lauren Hovde May 3, 2010 Pag / e2of3 " COMMENT #4: ACTION: COMMENT #5: ACTION: COMMENT #6: ACTION: COMMENT #7: ACTION: COMMENT #8: ACTION: COMMENT #9: ACTION: COMMENT #10: ACTION: COMMENT #11: ACTION: COMMENT #12: ACTION: COMMENT #13: ACTION: COMMENT #14: ACTION: COMMENT #15: ACTION: COMMENT #16: Show existing 20' PUE and PDE (4421/24) and confirm it extends to bounds of platted property. The easement has been added to the plat in accordance with the description in (4421/24). Add stop sign to Crosswater Drive at Congressional Court. See revised sheet 2. Relocate end of street signs to end of Birkdale Drive. See revised plans. Additional erosion control measures needed during construction at end of Birkdale. Why do the erosion control measures not include construction of storm sewer to outfalls? Silt fencing stops short of all the outfalls. See revised plans. The silt fence has been extended on Birkdale and to the top of the headwalls for the storm drain outlets. Some easement calls appear on Sheet 3, but lines don't show. See revised plans. It appears that the lighting plan requires additional PUE dedication. I discussed this issue with Eric Horton. He informed me that the electric line along Birkdale will be installed within the ROW. All of the other lines are covered by easements. Please check all sheets. Conflicts called out with notes, but no conflict shown and some conflict notes point inside pipe profile. See revised plans. What is gray line and SE2.1 notation indicate? See revised plans. What is slope of bank at culvert outlet at intersection of St. Andrews and Birkdale? In combination with outfall velocity what is appropriate surface treatment? See surface treatments added to this area on sheet 5. All sewer services need to be installed to within 3.5 feet of top of ground. (Our standard detail is not clear.) SS -1.7 looks correct, but the other services are not depicted the same way. A note has been added to the plan view of the sewer sheets that all services are within 3.5' of proposed /existing grade. The profile view has been updated to match 1.7. Confirm blowoff installed to top of proposed grade. See revised plans. Provide standard water and sanitary details. See revised plans. Please clarify response to previous Comment #18. We don't allow deflection in the joints of pipe. Isn't this the same thing? F: \1065 - Davis Young \0013 - Pebble Creek - Phase 9I \Correspondence \COCS - Response Letter - 050310.doc .• ■ Lauren Hovde May 3, 2010 Page 3 of 3 ACTION: The joints are different than fittings. The fittings (bends, tees, anchor couplings, valves, etc.) are constructed with mechanical joints that allow up to a 2.5 degree deflection. This method of deflection has been used in our plans for many years. COMMENT #17: Response to previous Comment #22 refers to revised exhibits, but these were not attached. ACTION: See attached exhibits. Sincerely, L ery . Robortson, PE e- President Engineering cc: Davis Young, Pebble Creek Development via fax # 979 - 690 -6081 F: \1065 - Davis Young \0013 - Pebble Creek - Phase 9I \Correspondence \COCS - Response Letter - 050310.doc Re.: April 19, 2010 Ms. Bridgette George Planning & Development Services City of College Station P.O. Box 9960 College Station, Texas 77842 PEBBLE CREEK PH 91 (FP) — Engineering Plans Staff Review Response MBESI #: 1065 -0013 Dear Ms. George: Below is the summary of the revisions made per staff's comments. ENGINEERING: COMMENT #1: Construction plans need to reflect infrastructure extension to limits of approved Preliminary Plat. ACTION: See revised plans. Provide a cost estimate, NOI and "Letter Acknowledging City Standards" See attached for cost estimate and Letter Acknowledging City Standards. The NOI was submitted previously with the contractor section left blank. Once the contractor is selected a completed NOI will be submitted. COMMENT #2: ACTION: COMMENT #3: ACTION: COMMENT #4: ACTION: COMMENT #5: ACTION: COMMENT #6: ACTION: COMMENT #7: ACTION: McCLURE & BROWNE, ENGINEERING /SURVEYING, INC. 1008 Woodcreek Dr., Suite 103 College Station, Tx. 77845 (979) 693 -3838 Engineer Reg. No. F -458 1314 10th Street, Suite 210 • Huntsville, Tx. 77320 (936) 294 -9749 Survey Reg. No. 101033 -00 Provide signage and Tight plan. See revised plans. Provide lot grading plan for Tots with cross - drainage. See revised plans. Note: Roadway fill shall be in accordance with BCS Technical Specifications. See revised plans. It appears a slope easement is required in common area at Birkdale /St. Andrews intersection. There is a utility and drainage easement covering the sloped area around this intersection. Both of these types of easements allow for maintenance of public infrastructure. We believe a slope easement is not needed in this area. How will the City get access to the outfall behind Tots 97 and 98 for maintenance? The fences for lots 97 and 98 can be stopped short of the property line to allow an accessway. Bridgette George April 19, 2010 Page 2 of 3 COMMENT #8: ACTION: COMMENT #9: ACTION: COMMENT #10: ACTION: COMMENT #11: ACTION: COMMENT #12: ACTION: COMMENT #13: ACTION: COMMENT #14: ACTION: COMMENT #15: ACTION: COMMENT #16: ACTION: COMMENT #17: ACTION: COMMENT #18: ACTION: COMMENT #19: ACTION: COMMENT #20: ACTION: COMMENT #21: ACTION: Appears additional PUE width is required on storm pipe between Inlets 7 and 8. See revised plans. Indicate limits of structural fill for storm pipe. See revised plans. Label minimum separation distances between utilities in question. See revised plans. What is 100 -year flowpath at end of Congressional Court? The outfall pipe for this cul -de -sac has been sized to accommodate the 100 -year flow. PUE required on sanitary sewer extension east of Birkdale Drive. See revised plans. Show storm sewer conflict near MH1.1 (Sheet 10). See revised plans. Maximum stack depths are 3.5 feet below top of ground. See revised plans. Relocate manhole to property line between Lot 101 and 102, so private service does not cross 102. See revised plans. Show waterline conflict on SE -2. See revised plans. Verify service taps are installed to within 3.5' of top of ground on existing sewer line at rear of lots on Congressional. See revised plans. What is means of vertical deflection at Sta 201 +31, WA -1? The vertical deflection is at a fitting. There are several fittings at this location (tee, valve, and anchor coupling). Each fitting can allow up to a 2.5 degree deflection per manufactures recommendations. Two valves are also required on tees for hydrants, Sta 205 +00 WA -1. See revised plans. FYI, detail W1 -02 needs to be updated to show this requirement. 8 -inch water line depicted in plan view, 6 -inch in profile, WA -2. See revised plans. Specify TCEQ crossing requirement for WA -2 crossing SE -2. Texas Administrative Code, Title 30, Part 1, Chapter 290, Subchapter D, Rule 290.44 (e)(4)(B)(iv)(II) All sections of wastewater main or lateral within nine feet horizontally of the waterline shall be encased in an 18 -foot (or longer) section of pipe. Flexible encasing pipe shall have a minimum pipe stiffness of 115 psi at 5.0% deflection. The encasing pipe shall be centered on the waterline and shall be at least two nominal pipe F: \1065 - Davis Young \0013 - Pebble Creek - Phase 9I \Correspondence \COCS - Response Letter - 041910b.doc Bridgette George April 19, 2010 Page 3 of 3 COMMENT #22: V ACTION: COMMENT #23: ACTION: COMMENT #24: ACTION: COMMENT #25: ACTION: COMMENT #26: ACTION: COMMENT #27: ACTION: COMMENT #28: ACTION: Si / , erely, diameters larger than the wastewater main or lateral. The space around the carrier pipe shall be supported at five -foot (or less) intervals with spacers or be filled to the springline with washed sand. Each end of the casing shall be sealed with watertight non - shrink cement grout or a manufactured watertight seal. An absolute minimum separation distance of six inches between the encasement pipe and the waterline shall be provided. The wastewater line shall be located below the waterline. Sewer report: Notes and conclusions refer to values in red, but tables are in black and white. Is Exhibit H that is called out in conclusions actually Exhibit G? The 8" section of sewer line is not listed in the Sewer Analysis. See revised exhibits attached to this letter. Drainage Report: Please provide hydraulic gradeline profiles. See attached exhibits. Drainage Report: Verify depth of flow of for design storm does not exceed top of curb for both standard 6" curb and layback curb. Provide depth of flow at inlets. Gutter flow depth is shown on Exhibit C -2. Note that for Drainage Area 10A the 100 year event was used for design. The gutter flow for the 100 year storm is 0.42' which is above the curb but contained within the ROW The 10 year gutter flow for the Drainage Area is 0.37' which is below the top of curb. Drainage Report: Verify storm water stays within ROW for 100 -year storm on local streets and leaves 12 -foot clear lane on collector. See Exhibit C -2. Drainage Report: Report and Technical Design Summary are not sealed. See revised documents. Drainage Report: Explain discrepancy between roughness coefficients used in your report and those provided in design guidelines. See attached sheets. Drainage Report: Explain "no" response to "Encroachment into floodplain planned ? ", when several of the lots have floodplain and /or floodway within their boundaries? Some of the lots are in the floodplain. It is not planned to do any fill within the floodplain. Additionally, notes on the final plat limit the activity that can occur in the floodplain. COMMENT #29: Drainage Report: Confirm FIS Floodplain elevations were utilized for tailwater conditions. ACTION: Floodplain elevations were used from a previous HEC -RAS study of the area for the future extension of Birkdale Drive. These elevations are slightly higher than the FIS elevations. ertson, PE nt Engineering cc: Davis Young, Pebble Creek Development via fax # 979 - 690 -6081 F: \1065 - Davis Young \0013 - Pebble Creek - Phase 9I \Correspondence \COCS - Response Letter - 041910b.doc