The URL can be used to link to this page

Home My WebLink AboutDrainage Reports - 01/07/1998Final Anr%rrw. 4d RV01t �•Ckati. { PARCEL "A" OUTFALL SEWER EROSION CONTROL and ADDENDUM TO "FINAL REPORT FOSSIL CREEK STABILITY STUDY TRILBY ROAD TO LEMAY AVENUE" v 1 1 1 1 1 1 1 PARCEL "A" OUTFALL SEWER EROSION CONTROL and ADDENDUM TO °FINAL REPORT FOSSIL CREEK STABILITY STUDY TRILBY ROAD TO LEMAY AVENUE" Prepared for: Huntington Hills LLC of Colorado A Colorado Corporation 650 South Cherry Street, Suite 435 Denver, Colorado 80222 Prepared by: JR Engineering, Ltd. 2620 East Prospect Road, Suite 190 Fort Collins, Colorado 80525 (970)491-9888 October 27, 1997 Job Number 9018.12 ' T� Engineering, Ltd. JJ 2620 East Prospect Rd. Suite 190 ' Fort Collins, Colorado 80525 (970) 491-9888 • FAX (970) 491-9984 www.jreng.com October 27, 1997 ' Mr. Matt Fater City of Fort Collins Stormwater Utility ' 235 Mathews Street Fort Collins, Colorado 80524 ' RE: Parcel "A" Outfall Sewer Erosion Control and Addendum to "FINAL REPORT FOSSIL CREEK STABILITY STUDY TRILBY ROAD TO LEMAY AVENUE" Fort Collins, Colorado 1 Dear Matt: 1 1 n 1 JR Engineering, Ltd. is pleased to submit the attached Parcel "A" Outfall Sewer Erosion Control and Addendum to "FINAL REPORT FOSSIL CREEK STABILITY STUDY TRILBY ROAD TO LEMAY AVENUE", originally prepared by Lidstone & Anderson, Inc., October 9, 1992, (LA Report), for your files. The analysis was performed in accordance with the specifications set forth in the City of Fort Collins' "Storm Drainage Design and Criteria Manual", the information presented in the aforementioned LA Report, and discussions with the City and Brad Anderson of Lidstone & Anderson, Inc. If you have any questions regarding the procedures, methodology, or results presented herein, please do not hesitate to contact me at your convenience. Sincerely, JR Engineering, Lt ' David Klockeman, P.E Project Manager ' Attachment 4935 North 30th Street Colorado Springs, Colorado 80919 (719) 593-2593 • FAX (719) 528-6613 6020 Greenwood Plaza Blvd. 704 Fortino Blvd. West Englewood, Colorado 80111 Pueblo, Colorado 81008 (303) 740-9393 • FAX (303) 721-9019 (719) 583-2575 • FAX (719) 583-8119 PARCEL "A" OUTFALL SEWER EROSION CONTROL and ADDENDUM TO "FINAL REPORT FOSSIL CREEK STABILITY STUDY TRILBY ROAD TO LEMAY AVENUE" Prepared for: Huntington Hills LLC of Colorado A Colorado Corporation 650 South Cherry Street, Suite 435 Denver, Colorado 80222 Prepared by: JR Engineering, Ltd. 2620 East Prospect Road, Suite 190 Fort Collins, Colorado 80525 (970)491-9888 October 27, 1997 Job Number 9018.12 I ' I. EROSION CONTROL Erosion and sedimentation will be controlled on -site by the use of silt fence and straw bale barriers which will be installed prior to commencing any earthwork operations. The measures are designed ' to limit the overall sediment yield increase due to construction as required by the City of Fort Collins. A construction schedule is contained in the Appendix which shows the proposed construction starting in November 1997. DUST ABATEMENT ' During the performance of the work required by these specifications or any operations appurtenant thereto, whether on right-of-way provided by the City or elsewhere, the Contractor shall furnish all labor, equipment, materials, and means required. The Contractor shall carry out proper efficient ' measures wherever and as necessary to reduce dust nuisance, and to prevent dust nuisance, and to prevent dust which has originated from his operations from damaging crops, orchards, cultivated ' fields, and dwellings, or causing a nuisance to persons. The Contractor shall be liable for any damage resulting from dust originating from his operations under these specifications. ' MAINTENANCE All temporary and permanent erosion and sediment control practices must be maintained and repaired as needed to assure continued performance of their intended function. Maintenance is the responsibility of the Owner. PERMANENT STABILIZATION Disturbed areas and soil stockpiles shall be seeded and mulched within 30 days of disturbance. ' Areas to be seeded and bank stabilized with North American Green SC 150 or equivalent shall also be completed within 30 days of disturbance. Vegetation shall not be considered established until a ground cover is achieved which is demonstrated to be mature enough to control soil erosion to the satisfaction of the City Inspector and to survive severe weather conditions. [1 1 1 CERTIFICATION "This plan for the Erosion Control design for the Parcel "A" Outfall Sewer was prepared by me (or under my direct supervision) in accordance with the provisions of the City of Fort Collins Storm Drainage Design Criteria and Construction Standards, for the owners thereof. I understand that the City of Fort Collins does not and will not assume liability for drainage and erosion control facilities designed by othggghmieu,,, Davi V. Klockeman, P.E. Colorado Registered Professional For and on Behalf of JR Eneineer M PA /Z 19- `Z7 Date I t II. ADDENDUM TO FOSSIL CREEK STABILITY STUDY ' PURPOSE ' The purpose of this portion of this report is to amend a portion of the Erosion Buffer Limit as defined in the "Final Report - Fossil Creek Stability Study, Trilby Road to Lemay Avenue", prepared by Lidstone & Anderson, Inc., dated October 9, 1992 (LA Report). The portion of the Erosion ' Buffer Limit to be amended is located within Southridge Greens Golf Course along the southwesterly side of Fossil Creek from Lemay Avenue to the Golf Course Maintenance Shop. This addendum is based on a review of the LA Report, discussions with City Stormwater Staff and Brad ' Anderson of Lidstone & Anderson, Inc.(LA), and field survey of cross-section information by JR Engineering, Ltd. (JR). ' REVISIONS TO EROSION BUFFER LIMITS The information utilized in the LA Report for this section of Fossil Creek was determined from ' aerial mapping in this area that was completed in the 1980's at 100 scale with a contour interval of 2 feet. As part of the preparation of the Parcel A Outfall Sewer plans by JR, field survey was completed through this section. Then, the Erosion Buffer Limit delineated in the LA Report was ' superimposed over the current field survey. It was noted that the Erosion Buffer Limit did not seem to match the existing topography. Therefore, discussions were initiated with City Stormwater Staff ' and Brad Anderson of LA in order to determine a course of action to properly identify the Erosion Buffer Limit. After discussion and field visits, it was determined that the proper course of action would be to field survey the creek cross sections and re-establish a portion of the Erosion Buffer Limit based on the criteria stated in the LA Report. Section 3.3.4, Buffer Limits, of the LA Report states that: ' "The buffer limit with respect to the banks situated against valley fill accommodates the maximum 40-year extent of lateral migration adjusted to the recent increase in rate of migration. This distance was estimated at 40 feet from the toe of the channel bank.... To accommodate this, the Culmann theoretical analysis and the strength characteristics of the soils establishes that bank failure will ultimately fail to an approximate angle of 33 degrees or 1.5H:1 V slope...." As a result of this information and discussions with Brad Anderson, it was determined that the section of the Erosion Buffer Limit in question would be re-established at a distance of 40 feet from ' the existing channel plus the distance to catch the existing ground at a 1.5H:1 V slope. (See attached plan for cross -sections and location of re-established Erosion Buffer Limit.) 1 3 I SUMMARY In summary, the Erosion Buffer Limit along the southwesterly side of Fossil Creek within Southridge Greens Golf Course from Lemay Avenue to the Golf Course Maintenance Shop has been re-established. This was completed by applying the criteria established in the LA Report to current field survey information after coordination with City and LA personnel. I III. REFERENCES 1. "Final Report - Fossil Creek Stability Study Trilby Road to Lemay Avenue", prepared by Lidstone & Anderson, Inc., dated October 9, 1992. 2. City of Fort Collins, "Storm Drainage Design Criteria and Construction Standards", (SDDCCS), dated May 1984, Revised January 1997 1 I I I 1] I I I 11 I I 4 I 11 APPENDIX A EROSION CONTROL COST ESTIMATE AND SCHEDULE r I r [1 I I I I I I [1 I JR Engineering, LTD 2620 E. Prospect Rd., Suite 190, Fort Collins, CO 80525 CONSTRUCTION SEQUENCE STANDARD FORM C PROJECT: PARCEL "A" OUTFALL SEWER SEQUENCE FOR 1997/1998 ONLY COMPLETED BY: DWK DATE: 10/29/97 Indicate by use of a bar line or symbols when erosion control measures will be installed. Major modifications to an approved schedule may require submitting a new schedule for approval by the City Engineer. 1997 1998 MONTH NOV I DEC I JAN I FEB MAR APR MAY JUN JUL AUG SEP Demolition Grading/Trench Excavation Wind Erosion Control: Soil Roughing Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant Other Rainfall Erosion Control Structural: Sediment Trap/Basin Inlet Filters Straw Barriers Silt Fence Barriers Sand Bags Bare Soil Preparation Contour Furrows Terracing Asphalt/Concrete Paving Other Vegetative: Permanent Seed Planting Mulching/Sealant Temporary Seed Planting Sod Installation Nettings/Mats/Blankets Other BUILDING CONSTRUCTION STRUCTURES: INSTALLED BY: CONTRACTOR MAINTAINED BY: DEVELOPER VEGETATIONIMULCHING CONTRACTOR: TO BE DETERMINED BY BID DATE SUBMITTED: APPROVED BY CITY OF FORT COLLINS ON: x:\901812\Erosion.xls COST JOB NO. 9018.12 EROSION CONTROL MF.ASi1RRS PARCEL "A" OUTFALL SEWER EROSION CONTROL COST ESTIMATE COMPLETED BY: DWK ITEM DESCRIPTION UNITS I UNIT COST IQUANTITY I TOTAL COST 1 SILT FENCE LF $ 3.00 3,400 $ 10,200.00 2 STRAW BALES LF $ 3.25 60 $ 195.00 3 RESEED/MULCH AC $ 650.00 4 $ 2,600.00 4 EROSION BLANKET SY $ 10.00 700 $ 7,000.00 PRELIMINARY COST $ 19,995.00 CITY RFSFFnINn COST ITEM DESCRIPTION UNITS I UNIT COST lQUANTITY TOTAL COST 1 RESEED/MULCH ACRE I $ 650.001 4.2 1 $ 2,730.00 PRELIMINARY COST $ 2,730.00 TOTAL PRELIMINARY COST $ 19,995.00 TOTAL COST WITH FACTOR OF 150% $ 29,992.50 ESCROW AMOUNT = $ 29,992.50 Page 1 I 1 1 1 1 1 1 APPENDIX B EROSION BUFFER PLAN AND CROSS -SECTIONS I I ♦'^� `\♦\`\1\1'' ('i!y I \ ------------ E%ISTING CONTOURS (Y) EMSTING PROPERTY LINE I_I- \`�Ty'• 4y p4 ` \ - -twp- - EXISTING INOE% CONTOURS (5') EXISRNG DECIDUOUS TREE __ _ PROPOSED PERMANENT EASEMENT `�' �iy4 It _ PROPOSED CONSIEASEMENT EXISTING CONIFEROUS 1REE a� —1T sAx- EXISTING SEWERLINE NE WW1TH1H MANHOLE—•—°-0— EXISTING CAS EXISTING ELECINC ♦ _ C -p' w- — - E%ISRNG WATERLINE I PROPOSED SEWERUNE WITH MANHOLE � 1 \ —� E%ISVNG TELEPHONE SOV a EIDSTING CABLE IELl:N810N � \ Gol, COV$E A . ♦ I n 1� / n � ,.. \\a ,.�.. � I/ I ++iiuu++, � ♦,., 1,# � �T-,...._.._._.e �`.� \ ,m.,Ls "+r. _ .. s-.a. _ .+nr.. ..._'I _ ma+ma� — � \ y.:... `.... � � I Fy . _ \\\ `\ `i ♦ �.� _ _. '.. i // F i( _•'�=y) r"^r"{6I'YIM i fl\'III 1 FO `rA ?'r •t � I� � \ II \\ /�\_.i— Ili •� `\ i) // //.�y/'�1____ _ 1'�\ ew\ *♦ \\\\ \ \\ \., '♦-`—� I \ �4yPo / / / \ \\ \ \ ♦l\ � \ � \ f// / / - / � Alf ,'' *� � " ��` � ��_) "/i \ / �\ TERM ow \ \ \ `6\\ \ `�___- --� .I �T Ste_ `�Y�/ /.�/ ///f ��♦ �9 _ "_ILIs � / \ rt[ \ / /��♦ -_\ - i--MARE _—.. \♦ /_ p4F COUR SE vif"D E. G 50 25 0 -------- _ HORIZONTAL SCALE: 1" - 50' / VERTICAL q�� . c\ , ( SCALE: 1' - 5' � 4915 CO. EROSON ER090N ,Q^4 V `RUfFER LIMIT DUFFER LIMIT / 4905.00 F OWLINE FOSSIL ME DATf/Y Tee 1895.00 / .K qY M V M O.00 5z77 100.00 1 SECTION 1 1 TIME SCALE: 1--50' VERY. SCALE: 1'a10' 's SECTION 2 HOR. SC I VERY. SCALE: I'=10' 9 .OLNE OF O [ 5L CREE% FOS DAa000 62.89 10000 3 SECTION 8 4 SECTIONn10 4 1 NOR. SCAM ALE: 1'=50' I II1I"=I - VERT. SCALE: 1".10' VERY. SCALE: 1'=10' � - T1 4910.00� 4915A / i ( 3 EROSION EROSI 5 BUFFER / I BIIFFE � 6 LIMIT � j / L1MR. -. .. _ 48901 4900. ON 4890.OU R 4895.00 BUFF R / 11 FLOWLINE OF� - y LIMIT FETNE CIE FOSSIL FOSSIL GREW E ROWLNE OFF` I FOSSIL CREEK FOSSIL CREEK DATUM AT6V DAIYDF 6 V y DA" KL l 4890A 1 4BBB. pD 0.00 6039 100.00 4m..BB E 488500 U.00 47.47 100.No FLONLNE of 4o ao'-I FMSTL CREEK SECTION! 9 a SECTION 7 9 l T HOR. SCALE 1'-50' 1 HER. S� DAMNVERL SCALE: I"=10' � VERY. SCALE: I'=10' 4BB0w 00 .lb -64.91 1W NO A SECTION 8 6 I NUR. scALF: 1'-50' - WRE SCALE: 1'=10' �9U�. R _. 4915 CO BUFFER - UFFER LIMIT FLOWIINE CF� -OSSL CREEK p Ra DAMN d 410SOIT- 0.00 66 IF 100. 5 SELECTION S IIOR SCA:"- 50' VERT SCALE 1"=10' LIMIT FOSSIL GREW1-1 ar DAft/Y £/617 '219 100.00 4BB300 0 too.00 IN /0 11 SECTION 11 -1'-50' I HOR. SCALE: 1'-50' 1"=10• M31T. SCALE: 1'=10' 6 SECTION 6 1 HORSC VERT. SCALE: I"=10' F cc0 a' ��N Ory6 D NIA==db� x - A W D! N � J 0 m � L➢ 1JQ I- to O 0 ) V1 _Z Q O �w J � U w K 'w SHEET 1 OF 1 A"Q(YI12