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HomeMy WebLinkAboutLot Certifications - 09/22/2017 (3)Date: September 8, 2017 Subdivision: 140669 - S14 T06 R69 Address: 309 West Trilby Road Lot: Fort Collins, Colorado 80525 Block: Permit Application #: B1603831, B1603832, B1603833 Larimer County Parcel #: 96141-00-009 Larimer County Reception #:.. A (on development agreement) I, (print) Kevin Forbes a Colorado registered professional engineer, verify that construction of all stormwater facilities and grading is complete and hereby submit this certification. Please answer the following questions by initialing the appropriate response. For each question initialed "No," attach an explanation detailing how this will affect stormwater drainage for this lot and any adjacent lots. 1. Certification includes attached Stormwater-approved grading plan. (NOTE: City's No Yes Building Department does not approve grading plans). 2. Certification includes attached as -built survey dated July 24, 2017 (must be within 60 No Yes days of date of certification) accurately and truthfully depicting elevations for: • Top of foundation/finished floor • Finished grade on each side of the structure • Quarter points along each lot line (not more than 50 feet apart) • Break points/high points • Swales • Berms • Retaining walls • Air conditioning pads • Window wells • Any other appurtenance(s) within an easement 3. All elevations are within a 0.2 foot tolerance of the approved grading plan. No Yes 4. The top of foundation is at least 6 inches above the highest grade surrounding the No Yes structure. 5. There is a minimum grade of 5% away from the structure within the first 5 to 10 feet No Yes adjacent to the residence. 6. All slopes meet or exceed the minimum requirement of 2% (1% is acceptable on single No Yes Vc- family lots when the swale is draining the runoff from only two adjoining properties) and are not steeper than 25% (4:1). 7. All flow lines of stormwater drainage swales are a minimum of 6 inches below the No Yes elevation of ground adjacent to the structure and will direct drainage as shown on the Stormwater-approved grading plan. 8. All downspout locations and discharge directions are shown on the as -built survey. No Yes Runoff is not directed toward neighboring properties. 12/15 Page 1 9. A smooth transition (no grade break) is provided to all adjacent properties. No Yes 10. The grading of this lot does not adversely affect neighboring properties or City No Yes infrastructure. 11. Landscaping has been completed prior to survey. If not, please indicate who will be No Yes responsible for completing landscaping: Don Homolka, (Property Owner) 12. Final site cleanup has been completed. No Yes 13. 1 personally visited the site as part of the certification process, and in my professional No Yes opinion, the as -built survey is an accurate representation of the site conditions. 14. Based on this information, I certify that (check one): ❑ The elevations and drainage patterns of the lot/site are in substantial conformance with the City approved drainage and grading plan for the property (information attached). The elevations and drainage patterns of the lot/site as measured are in general conformance with the City approved drainage plan with exceptions (information attached). In my professional judgment the elevations and grading of the lot/site as constructed are functionally adequate and equivalent to the specifically approved drainage plan, and will affect stormwater drainage on and off the lot/site in a manner consistent with the approved drainage plan. 0 E. N a 265 r 7 . r PE Stamp Sign and date Name: Kevin Forbes Email: kevinforbes@frii.com Phone: (970) 295-4874 Company: Forbes Engineering LLC Address: 2908 Cherly Street Fort Collins, Colorado 80524 NOTE: A complete certification must be submitted at least two weeks prior to a request for a Certificate of Occupancy for the lot/site, including, but not limited to, drawings of the lot/site showing the approved design and as -built surveyed elevations of all structures, drainage and grading features, written information/explanation of discrepancies, and other information necessary to confirm the above certification to: Email (preferred) WaterUtilitiesEng@fcgov.com Mailing Address Fort Collins Utilities ATTN: Water Utilities Engineering 281 North College Avenue Fort Collins, CO 80521 Questions? 970-221-6700 Fort Collins Utih!rt>s 12/15 Page 2 FORBES ENGINEERING Full Service Civil & Structural Engineering September 12, 2017 Dan Mogen Fort Collins Utilities ATTN: Water Utilities Engineering 281 North College Avenue Fort Collins, CO 80521 RE: Non-compliance to Certification of Lot Grading 309 West Trilby Road, Fort Collins, Colorado 80525 Mr. Mogen, During the as -built grading survey on this lot, it has come to my attention that the inspected property does not comply with items 3, 4 & 5 of the Certification of Lot Grading form. The following is the certificate of grading check list questions along with a brief explanation of why each item does not comply as well as a brief description as to how the changed condition can function as required; 3. All elevations are within a 0.2 foot tolerance of the approved grading plan. • Site grading deviates from the approved grading plan mainly due to the raised finish floor elevations of the new buildings. Also, site grading has been modified to allow for the north drainage to flow through the pasture instead of along the east edge of the property. • Though it is not the ideal situation, the raised building elevations does not create problems with site drainage and the new location of the swale will redirect storm water run-off towards the north and function as needed. • The original location of the north swale was along the west side of the shared access drive and was intended to capture as much stormwater drainage coming off of the site towards the east. The intent was to protect the shared access from sediment coming off of the site and to allow the site time to acquire adequate ground cover. The area of the site that will now flow unimpeded onto the road is small and should not create too much sediment, though this situation should be monitored and any excess debris cleaned up when necessary. 4. The top of foundation is at least 6 inches above the highest grade surrounding the structure. • The grade surrounding the buildings was built at a higher elevation than what was originally designed; this has created a situation where there is less than the desired revel along the foundation. • Again, this is not the desired condition but the buildings are being used as commercial storage buildings which are of steel construction on monolithic concrete pads, so the impact will be minimal. 5. There is a minimum grade of 5% away from the structure within the first 5 to 10 feet adjacent to the residence. • As described previously, the grade surrounding the structures is higher than the original design. This creates a flatter slope away from the buildings. • Though the grade is not the desired slope, it will still shed stormwater run- off out and away from the buildings to portions of the site that slope at a greater rate. It is my opinion that the changes to the original design have been modified to adequately shed stormwater run-off out and away from the structures and will adequately convey the required stormwater flows towards the north and ultimately off the site. I hope this letter covers your concerns. Please don't hesitate to call if I can be of further service or if you have any questions. I can be reached at (970) 232-6014. O Sincerely, '3 ., . Kevin Forbes, 3��,¢S.-O SITE GRADING AS —BUILT SURVEY PROPERTY DESCRIPTION: Portion of the NE X of Section 14 Township 9 North, Range 69 West of the 6th P.M., City of Fort Collins, County of Larimer, State of Colorado. 309 West Tr; Roa � _ � � ` � \ �\ \\ \ � •\ � \ �I,( \\I � bQ 0. `n 1 \ LOT 16 LOT 161 L i / 6.4 \ , a— �/ n 1.6 0.9 9.5 �L— 6.Y --- - L 3.2'8.0'—� �gr \I \ x SO 9.5 8.8 8.0 f-- 5Z 3.0'�— 65' 4 SURVEYOR'S STATEMENT: I, Ricky J Lewis, being a duty Registered Land Surveyor in the State of Colorado, do hereby state that on July 24, 2017, a field crew under my direct supervision observed the as -built conditions of this project, and that the spot elevations, cross -sections, and flow direction arrows shown hereon are actual field conditions on this date. Elevations shown hereon are referenced to City of Fort Collins Benchmark No. 38-49, Elevation 5093.76 ® INDICATES DOWNSPOUT LOCATION RJL SURVEYS .0111, 3031 Maryland Place Loveland, Colorado 80525 Tel: (970) 775-7495 pp REG-i, SCALE I DATE I DRAWN BY I ADDRESS I REVISED FILE I 1"=50' 09-18-2017 RJL 1 309 WEST TRILBY ROAD, FORT COLLINS, COLORADO 1 23,694 217 WEST TRILBY ROAD PN 96141-00-012 r r / I r- I _ -_ I I I I I I I I i I I I I I I I ' I 1 1 1 V 1 i 1 I 1', I ' I I I LEGEND: SEDIMENT CONTROL FENCE / hob i l i j j l f i i i I i i "K,a/ CUT-OFF SWALE SLOPED ® APPROX. 5%, SEE SHEET C2 FOR DETAILS EXISTING-- ---- -------�HEDS-�TYPr� -_--�06% ,A 2.44 O N N 0pb Cb / ,GRAYLIDRIVi=._I -,i L i / I I -I ----�-- I iL__-I TRACT K RIDGEWOOD HILLS DETENTION POND SITE BOUNDARY/PROPERTY LINE ADJACENT LOT LINE - - EASEMENT LINE - - - - - - - - - - - - - - - PROPOSED BUILDING SWALE CENTERLINE SEDIMENT CONTROL FENCE -- ---- x PROPOSED CONTOUR EXISTING CONTOUR----5232--------- CONTOUR MATCH POINT - - - - - -�--�- CENTERLINE OF ROAD ------ -- --- EDGE OF ASPHALT - - - - - - - GRAVEL DRIVE ------------ ---- SPOT ELEVATIONS EXISTING 308E PROPOSED�- 225 WEST TRILBY ROAD PN 96141-00-015 - EXISTING SHARED PROPOSED RECYCLED GRAVEL ACCESS ROAD ASPHALT ACCESS DRIVE '--------------- - -- \I It 1 \1 1,1, \\ I \% \ �------ \ \ \ 11 -------- � ---' 5081 EARTH BERM -- EXISTING RESIDENTIAL HOME - PORTION OF OFF -SITE FLOW APPROXIMATELY 2522 SF DRAINAGE SUMMARY HISTORIC CONDITION BASIN AREA, SF AREA, AC CO00) Q(2),cfs Q(100),cfs A 106,347 2.44 0.35 1.23 5.55 B 62,283.5 1.43 0.31 0.60 2.75 TOTAL 168,630.5 3.87 1.83 8.30 DEVELOPED CONDITION A 1 152,802.5 3.51 0.39 1.85 1 8.08 B 1 15,828 0.36 0.31 0.22 0.95 TOTAL 168,630.5 3.87 2.07 9.03 2 YEAR RUN-OFF INCREASE = 0.24 CFS 100 YEAR RUN-OFF INCREASE = 0.73 CFS \ 10 \I \ FF=79.3\i \ \ Y p ��� n\ \ `\ \ \I \ It 1 1 ; 1It , 1 11 1 11 1 FF=80.0 \ 11 1; I N V I \ 1 1 1 1 11 ------------- �5080' S� PROPOSED RECYCLED - ASPHALT ACCESS DRIVE & PARKING ABBREVIATIONS FF FINISHED FLOOR EOA EDGE OF ASPHALT EOG EDGE OF GRAVEL FL FLOW LINE Z CENTERUNE RL RIDGE LINE ROW RIGHT OF WAY EOC EDGE OF CONC la1 d Q J W JU, W I\ J o J O I W = O =jl UJ O V) 00 00 i (o CL FG FINISHED GRADE EG EXISTING GRADE R, PROPERTY LINE TOE TOE OF SLOPE LP LOW POINT HP HIGH POINT TOS TOP OF SLOPE BOS BOTTOM OF SLOPE DRAINAGE LEGEND SURFACE FLOW DIRECTION (CONCENTRATED FLOW) .9..7ox DRAINAGE FLOW DIRECTION (PIPE FLOW & SLOPE) SURFACE FLOW DIRECTION (SHEET FLOW) Qp DESIGN POINT DESIGNATION A A=SUB-BASIN DESIGNATION B=AREA IN ACRES B C C=100 YEAR COMPOSITE RUNOFF COEFFICIENT 111 "' - PROPOSED LOCATION 111� X I �\ �-', Iv ` OF POLE BARNS SEE FF=80.7 �\ ? 111, 11 SHEET C2 FOR DETAILS 1 J \ \ Io l 1t 1\ b04 ------r 1 O� _co c- co c(o F- O O O --I J J GENERAL NOTES: RIDGEWOOD HILLS, PUD GRADING, DRAINAGE AND EROSION CONTROL PLAN SCALE 1 " = 30' I 30 0 30 60 GRAPHIC SCALE - FEET 1. THIS SITE IS NOT WITHIN ANY FLOOD ZONE, ACCORDING TO FLOOD INSURANCE RATE MAP 2. SURVEY DATA PROVIDED BY RJL SURVEYS DATED AUGUST 20, 2016 3. EXISTING AND PROPOSED CONTOURS ARE SHOWN AT ONE FOOT INTERVALS 4. BENCH MARK: ACBM 38-94 ELEVATION: 5093.76 (NAVO 88 DATUM) PROPERTY INFORMATION OWNER: DONALD & JUNE HOMOLKA 309 WEST TRILBY ROAD FORT COLLINS, CO 80525 PARCEL µ: 96141-00-009 ADDRESS: 309 WEST TRILBY ROAD FORT COLLINS, CO 80525 LEGAL: METES & BOUNDS, SEE SITE PLAN TOTAL AREA: 168,603.5 SF (3.87 AC) O O Q Q J Z w o O U m ov O Z E v; I-- Z m N J Q W z -j 0 CL Pr) O" o o a a L 0 i 2:1 Of g W7Z� G � U z a o 0 =Voz zoz w i 4 w ��� m "z J � O S s< LL 5 01 D.t• 8-26-16 soa• AS NOTED °•" KEF MrMid KEF 24'x36' GRADING & DRAINAGE \�P\,LAAN C-inq No. `/ 1 EXISTING SHARED 5 GRAVEL ACCESS ROAD / SEDIMENT CONTROL -- PROPOSED RECYCLED ASPHALT ACCESS DRIVE SEDIMENT FENCE CONTROL q FENCE C2 CL SWALE PROPERTY 15' LINE h° ---EOG - -- ---- -- -\ I // \ \ \ // ` \ �\ \ \ \ MATCH INTO t t EXISTING GRADE - 11 15' s• — 3. X— — X— -- \ \ \ \ It k It EXISTING GRADE COMPACTED EXISTING SHARED `�` , �\ PROPOSED CUT BERM GRAVEL ACCESS ROAD `k CROSS SECTION A -A I t �s 1 �t NOT TO SCALE \ SEDIMENT CONTROL I ! FENCE `V\79- \ FG MIRAFI MODEL 10100 \\ �� I I i I SILT FENCE \ -------------- r' \ i\ FF=80.0 A i i i i LATHE S' O.C. (TYP.) � �^ I`- \ - ---- _ —ATTACH SILT FENCE -- �\ --- ---- --- --- --- i� 1 / I I I BETWEEN LATHE & POSTS w/1 1 /4" ROOFING NAILS eo.a� DETAIL /� Fo DTI I Fo I 1 1/2" SQUARE x 48" LONG, KILN IGoDRIED POSTS 0� I FF=80171 I I Ili III \ I I I I ELEVATION NATIVE SOIL - COMPACTED BACKFILL 6" x 6" EXCAVATED `Y _ _ K/ 's� - I� `� INSPECT AND REPAIR FENCE AFTER TRENCH ---- ------ ---- --^-- _ 1=_ ___=__ 1-T Z �i / /i ,l �I �I �� �� EACH STORM EVENT. REMOVE RUNOFF FLOW $3�'---- --- ------ - _ _ --- _ - -- — — - — - SEDIMENT WHEN 6" OF THE HEIGHT , I OF THE FENCE HAS BEEN FILLED. _ ____ ----- i� / r� NATIVE SOIL ' REMOVED SEDIMENT SHALL BE `- ------rr ��;, PLACED IN TOPSOIL PILE. SECTION n SEDIMENT CONTROL FENCE -- NOT TO SCALE SITE IMPROVEMENT & GRADING DETAILS SCALE 1" = 20' O 0 0 Of JZ 00 O O U }0 O= 0E FEz o m 00 J W U Z J 0 0 00 a ag 01 Z 6v3 F5 LLB 8 b== LJa� Z 0 �Zo z _H LLJ �0 � Z cn LLJ m OJ O O a� LL 1. D,I, 8-26-16 S"' AS NOTED 0— KEF V.iflw KEF D—in a°' 24'x36- N— IMPROVEMENT DETAIL PLAN �°� C 2