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HomeMy WebLinkAboutLOFTS AT TIMBERLINE - FDP200007 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTPage 1 of 6 2133 S. Timberline Road, Unit 110 Fort Collins, CO 80525 ditescoservices.com Drainage Memorandum Date: February 3, 2020 Project: Lofts at Timberline Timberline Center, Lot 4, 6 and 7 Attn: Stormwater Staff, City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80521 To Whom It May Concern: The purpose of this report is to summarize the proposed drainage design as an addendum to the original Final Drainage and Erosion Control Report for the Timberline Center Subdivision as prepared by North Star Design; February 2006 - (North Star Report) and describe project conformance to LID standards. The new development is located in sub-basins 9, 10 and 17 of the original North Star Report. Basin flows are largely being maintained according to the original planned development. A summary table of basin sizes for the proposed project compared to the original development is provided below in Table 1. For the purposes of comparison, the original design references are labeled North Star Report or Overall Development Plan (ODP). The proposed project is labeled Proposed Project or Lofts. In an effort to simplify the basin comparisons, only the areas contained within Lots 4, 6 and 7 have been directly compared (see Figures 1 and 2 below). The original sub-basin sizes, in most cases are larger and traverse across multiple lots and roadways within the development. Appendix E contains exhibits that show a mapped comparison between the original and new basins. Table 1 Overall Development Plan Proposed Project (Lofts) Design Point Basin Area (acres) Q 10 (cfs) Q 100 (cfs) Design Point Area (acres) Q 10 (cfs) Q 100 (cfs) 9 1.43 4.8 12.6 9A, 9B 1.88 6.74 17.32 10 0.75 3.0 7.4 10B 0.42 1.76 4.18 17 1.80 6.4 17.9 17 1.67 6.7 16.63 Totals 3.98 3.97 Page 2 of 6 Figure 1 – Overall Development Plan Sub-Basin Comparison (on Lots 4, 6, 7) Figure 2 – Proposed Project Basin Delineation (on Lots 4, 6, 7) Page 3 of 6 Design Narrative Sub-Basin 9. Sub-basin 9 is predominately the area along the west and southwest side of the site comprising portions of Lots 6 and 7. Flows from this basin are routed into the inlet on the southwest corner of existing Lot 7 (original inlet B-4) in Joseph Allen Drive. The proposed site grading plan routes runoff through two new type 13 valley grate inlets south of the proposed building. These inlets route flow into the rear side of original inlet B-4 and on to the original pipeline B2. All flows are then routed to pipe in Joseph Allen Drive and north to Detention Pond A. To directly compare site contributory flows to that of the original North Star Report, this study shows the runoff areas in each sub-basin. See Table 1, Figures 1 and 2 and Appendix E contained in this report. Certain areas of sub-basin 9, are now included in basins 10 and 17 as shown in Figures 1 and 2 and Appendix E. Flows contributory to this new sub-basin 9 area have increased by 1.94 cfs for a 10- year storm and 4.72 cfs for a 100-year storm. However, while there is a slight increase in flows in sub- basin 9. Flows for sub-basin 10 have decreased by 1.24 cfs in a 10-year event and 3.22 cfs in a 100-year event (see Table 1). Both sub-basin 9 and 10 contribute flows to pipelines in Joseph Allen Drive and on to Detention Pond A. There is sufficient pipe capacity in Joseph Allen Drive to route all flows subsurface. Additionally, there is currently over 18-inches of freeboard in Detention Pond A where these flows will ultimately be routed. Sub-Basin 10. Sub-basin 10 is a central sub-basin to the site near the northwest portion comprising most of Lot 6 and a portion of Lot 7 (see Figures 1 and 2 above). Flows from this sub-basin are routed to design point 10B which is a planned double type 13 valley grate inlet. From this inlet, flows are then routed to a pipeline in Joseph Allen Drive and on to Detention Pond A. To directly compare site contributory flows to that of the original North Star Report, this study shows the runoff areas in each basin. See Table 1, Figures 1 and 2 and Appendix E contained in this report. For sub-basin 10, the original basin boundaries were all contained within the property, as is the case for the proposed project. For the proposed project, sub-basin 10 is decreased in size by 0.33 acres. Flows contributory to this new sub-basin 10 area have decreased by 1.24 cfs for a 10-year storm and 3.22 cfs for a 100-year storm (see Table 1). Sub-Basin 17. Sub-Basin 17 is the predominant basin on the site. It contains the majority of Lot 4 and small portions of Lot 7. Flows from this sub-basin are all routed east to design point 17 which is the existing Type R inlet (original inlet C-3) in the north-south access road. From this inlet, flows are then routed northeast to Detention Pond C. To directly compare site contributory flows to that of the original North Star Report, this study shows the runoff areas in each basin. See Table 1, Figures 1 and 2 and Appendix E contained in this report. For sub-basin 17, the original basin boundaries were all contained within the property, as is the case for the proposed project. For the proposed project, sub-basin 17 is decreased in size by 0.88 acres. Flows contributory to this new sub-basin 17 area have increased slightly by 0.30 cfs for a 10-year storm (slightly higher runoff coefficient for the proposed condition) and have decreased by 1.27 cfs for a 100- year storm (see Table 1). Page 4 of 6 Calculations for runoff, pipe and inlet sizing are included in Appendix A. Site Imperviousness and LIDs: The lots under consideration are lots 4, 6 and 7 of the 3rd Filing of the Timberline Center Subdivision. As proposed, the new design will modify the original overall development plan and construct a single flex use building vs. the multiple building complex envisioned in the ODP. The original lot configuration for the filing served three separate buildings and associated parking. The new site design includes a 26,000 SF building, parking, outdoor spaces and LID improvements which encompass 8,580 square feet of permeable pavers and a raingarden. Table 2, below show a comparative overview of the impervious and pervious areas from the new design and the original ODP. With the addition of pervious pavers, the impervious area has decreased by 9%. The overall area of landscaping between the original ODP and the updated design is very similar. With only a 535 square foot reduction in landscaping areas for a 2-acre site, this makes up only 0.6% of the site and is within a reasonable margin of error. Drawings that were utilized to calculate the areas for the proposed project design and the original ODP are included as Appendix B. Table 2: Impervious/Pervious Area Summary Timberline Lots 4,6,7 (proposed Lofts project) Timberline Center ODP Impervious Area Summary Impervious Area Summary Area Description Color Area-SF Area Description Color Area-SF Asphalt Grey 27,970 Asphalt Grey 42,050 Sidewalks Peach 7,770 Sidewalks Peach 11,235 Curb/Gutter Orange 2,300 Curb/Gutter Included in Asphalt and Sidewalk - Building Footprint Yellow 26,430 Building Footprint Yellow 18,365 Total Area 64,430 Total Area 71,650 Pervious Area Summary Pervious Area Summary Area Description Color Area-SF Area Description Color Area-SF Landscaping Beds Green 15,235 Areas Between Front Walks Green 15,975 Porous Pavers Blue 8,580 Total Area 23,815 Total Area 15,975 Impervious Percentage 73.0% Impervious Percentage 81.8% As the proposed project provides less impervious area when compared to the original design, the proposed project is in compliance with the original approved North Star Report. Page 5 of 6 Drainage Basin Compliance: Basins 9, 10, and 17 as outlined in the North Star Report have been modified slightly to account for the location and differing sub-basin routing conditions. It has been determined that these modifications will have negligible impact on the runoff that is routed to each of the design points (see analysis above and associated Appendices). Low Impact Development Compliance: Low Impact Development (LID) requirements according to Section 3.1 of the Urban Drainage and Flood Control District Manual (Fort Collins 2012 Amendments) (UDFCD) include:  Section 3.1(a)(1) water quality treatment for 50% of new impervious area  Section 3.1(a)(2) 25% of new paved areas must be pervious.  Or, per City of Fort Collins Ordinance No. 007, 2016; 75% of a newly developed area may be treated using a combination of LID techniques to achieve compliance. The proposed project includes 57,080 sf (1.31 acres) of new impervious area. The project will treat 37.7% of this area (21,497 sf) using permeable pavers and run-on to the pavers. The proposed project provides 27.3% of new impervious area as permeable pavers (8,396 sf) located in parking areas throughout the site. The project will treat 46% of the total new impervious area using a combination of LID treatments (both permeable pavers and a single rain garden). A summary LID Compliance Table is provided in Appendix D. Roof Drains The proposed project routes roof drain flows to subsurface piping throughout the site to minimize icing and increase safety. Roof drains along the east building roof line will be routed through the single rain garden provided as part of the project. Erosion Control A site-specific Erosion Control Report has been developed for the proposed project and is included in Appendix C. Summary In summary, the proposed project largely follows the original Overall Development Plan (ODP) concepts for stormwater runoff, collection and routing to detention facilities. Flows are slightly greater to less than what was originally designed. All infrastructure (on and off site) will accommodate the proposed design. While the 2005 ODP properly designed stormwater flow collection and routing, it did not contemplate Low Impact Development Standards (LID). The proposed project incorporates permeable pavers as the primary component of stormwater LID treatment. It also includes a single rain garden. The LID treatment standard is very closely met with 23% of the site as permeable pavers and 46% of runoff treated. All other drainage criteria both City of Fort Collins and Urban Drainage and Flood Control District Manual (Fort Collins 2012 Amendments) are met. Page 6 of 6 If you have any questions regarding this submittal, please do not hesitate to contact me by email at keith.meyer@ditescoservices.com or by phone at (970) 988-8605. Thank you for your attention and assistance in this matter. Sincerely, Jenna Beairsto, EI Keith Meyer, PE Enc. Appendix A – Runoff, Pipe Sizing and Inlet Design Calculations Appendix B – 3rd Filing Lot 1 Drawing of Impervious Areas; 2006 Drawing of Impervious Areas Appendix C – Erosion Control Report Appendix D – 3rd Filing Lot 1 LID Treatment Areas and Calculations Appendix E – Overall Drainage Basin Comparison Appendix A Runoff, Pipe & Inlet Sizing Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 COMPUTATIONS BY: JLB DATE: 1/7/2020 Runoff Coefficient C % Impervious Streets, parking lots (asphalt) 0.95 100 Sidewalks (concrete): 0.95 96 Roofs: 0.95 90 Lawns (flat <2%, heavy soil): 0.2 0 Basin Designation Total Area (SF) Total Area (AC.) Pavement/ Roof/ Sidewalk (SF) Lawn/ Mulched (SF) Runoff Coefficient (C) % Impervious Basin 9A 11,145 0.26 10,865 280 0.93 97.5% Basin 9B 7,820 0.18 7,130 690 0.88 91.2% Basin 10B 16,170 0.37 15,925 245 0.94 98.5% Basin 17 34,265 0.79 33,985 280 0.94 99.2% Basin Designation Total Area (SF) Total Area (AC.) Pavement/ Roof/ Sidewalk (SF) Lawn/ Mulched (SF) Runoff Coefficient (C) % Impervious 9 18,965 0.44 17995 970 0.91 94.9% 10 16,170 0.37 15925 245 0.94 98.5% 17 34,265 0.79 33985 280 0.94 99.2% RUNOFF COEFFICIENT & % IMPERVIOUS Recommend Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria Recommend % Imperivous from Urban Storm Drainage Criteria Manual Lofts at Timberline Time of Concentration Calculated By: JB Design Storm: 10 year tc tc = t i+t t Date: 1/7/2020 Site Calculations: Comp tc Final tc Remarks Basin Sub-basin Area Total Contrib. Area Ci *A Frequency Adjustment C2 Cf Length Slope ti Length Slope Roughness Coefficient Hydraulic Radius Velocity tt tc Comp tc Minimum No. (Ac) Area (Ac) Area (Ac) (ft) (%) (min) (ft) ft/ft A/P = D/4 (ft) ft/sec (min) (min) (min) (min) Basin 9 A 0.256 0.683 0.256 0.93 1.00 0.93 40 4.00% 1.26 182 0.023 0.015 0.25 5.98 0.51 1.77 11.23 1.77 5.0 Basin 9 B 0.180 0.683 0.18 0.88 1.00 0.88 100 1.40% 3.62 0 NA NA NA 0.00 0.00 3.62 10.56 3.62 5.0 Basin 10 B 0.371 0.421 0.37 0.94 1.00 0.94 90 4.00% 1.81 140 0.032 0.015 0.167 5.38 0.43 2.25 11.28 2.25 5.0 Basin 17 0.787 0.922 0.79 0.94 1.00 0.94 164.00 1.00% 3.74 113 0.025 0.015 0.21 5.52 0.34 4.08 11.54 4.08 5.0 Design Storm: 100 year Date: 1/7/2020 Cf =1.25, C100 not to exceed 1.00 Site Calculations: Final tc Remarks Basin Sub-basin Area Total Contrib. Area Ci*A Frequency Adjustment C2Cf Length Slope t i Length Slope Roughness Coefficient Hydraulic Radius Velocity tt tc Comp tc Minimum No. (Ac) Area (Ac) Area (Ac) (ft) (%) (min) (ft) (%) (fps) (min) (min) (min) (min) Basin 9 A 0.256 0.683 0.256 0.93 1.25 1.00 40 4.00% 0.75 182 0.023 0.015 0.25 5.98 0.51 1.26 11.23 1.26 5.00 Basin 9 B 0.180 0.683 0.180 0.88 1.25 1.00 100 1.40% 1.67 0 NA NA NA 0.00 0.00 1.67 10.56 1.67 5.00 Basin 10 B 0.371 0.421 0.371 0.94 1.25 1.00 90 4.00% 1.12 140 0.032 0.015 0.167 5.38 0.43 1.56 11.28 1.56 5.00 Basin 17 0.787 0.922 0.787 0.94 1.25 1.00 164.00 1.00% 2.39 113 0.025 0.015 0.21 5.52 0.34 2.74 11.54 2.74 5.00 Basin Data Initial/Overland Time (ti) Travel Time (tt) tc Check (urbanized basins) Basin Data Initial/Overland Time (ti)Travel Time (tt)tc Check (urbanized basins) �� = � 180 + 10 �� = 1.87 1.1 − �� �� �� Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: COMPUTATIONS BY: JLB DATE: 2/4/2020 Design Storm: 2 year Q=CIA Cf = 1.0 Design Point A (AC) C*Cf tc (min) I (in/hr) Q2 (cfs) 9A 0.26 0.90 5.00 2.88 0.7 9B 0.18 0.72 6.42 2.69 0.3 Lot 9 Proposed 1.0 Remainder of Lot 9 1.44 0.82 8.00 2.48 2.9 Total Proposed 3.95 ODP Total 3.38 Difference Between Proposed and ODP 0.45 Flow (Q): 0.57 10B 0.37 0.86 5.00 2.88 0.9 Lot 10 Proposed 0.92 Remainder of Lot 10 0.05 0.82 5.00 2.88 0.1 Total Proposed 1.03 ODP Total 1.77 Difference Between Proposed and ODP -0.33 Flow (Q): -0.74 17 0.79 0.90 5.22 2.88 2.03 Lot 17 2.0 Remainder of Lot 17 0.88 0.83 7.00 2.62 1.9 Total Proposed 3.95 ODP Total 4.30 Difference Between Proposed and ODP -0.13 Flow (Q): -0.35 Q = peak discharge (cfs) C = runoff coefficient I = rainfall intensity (in/hr) from IDF curve A = drainage area (acres) Area: Area: Area: Runoff for 2, 10 and 100 year storm events RATIONAL METHOD PEAK RUNOFF (NEW IDF CURVE) Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: COMPUTATIONS BY: JLB DATE: 2/4/2020 Design Storm: 10 year Q=CIA Cf = 1.0 Design Point A (AC) C*Cf tc (min) I (in/hr) Q10 (cfs) 9A 0.26 0.90 5.00 4.92 1.1 9B 0.18 0.72 6.42 4.60 0.6 Lot 9 Proposed 1.72 Remainder of Lot 9 1.44 0.82 8.00 4.24 5.0 Total Proposed 6.74 ODP Total 4.80 Difference Between Proposed and ODP 0.45 Flow (Q): 1.94 10A 0.37 0.86 5.00 4.92 1.6 Lot 10 1.57 Remainder of Lot 10 0.05 0.82 5.00 4.92 0.2 Total Proposed 1.76 ODP Total 3.00 Difference Between Proposed and ODP -0.33 Flow (Q): -1.24 17 0.79 0.90 5.22 4.92 3.47 Lot 17 3.47 Remainder of Lot 17 0.88 0.82 7.00 4.46 3.2 Total Proposed 6.70 ODP Total 6.40 Difference Between Proposed and ODP -0.13 Flow (Q): 0.30 Q = peak discharge (cfs) C = runoff coefficient I = rainfall intensity (in/hr) from IDF curve A = drainage area (acres) Area: Area: Area: RATIONAL METHOD PEAK RUNOFF (NEW IDF CURVE) Runoff for 2, 10 and 100 year storm events Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: COMPUTATIONS BY: JLB DATE: 2/4/2020 Design Storm: 100 year Q=CIA Cf = 1.25, (C@1.0 max) Design Point A (AC) C*Cf tc (min) I (in/hr) Q100 (cfs) 9A 0.26 1.00 5.00 9.96 2.5 9B 0.18 0.90 5.00 9.96 1.6 Lot 9 4.15 Remainder of Lot 9 1.44 1.00 6.90 9.12 13.2 Total Proposed 17.32 ODP Total 12.60 Difference Between Proposed and ODP 0.45 Flow (Q): 4.72 10A 0.37 1.00 5.00 9.96 3.7 Lot 10 3.7 Remainder of Lot 10 0.05 1.00 5.00 9.96 0.5 Total Proposed 4.18 ODP Total 7.40 Difference Between Proposed and ODP -0.33 Flow (Q): -3.22 17 0.79 1.00 5.00 9.96 7.8 Lot 17 7.83 Remainder of Lot 17 0.88 1.00 5.00 9.96 8.8 Total Proposed 16.63 ODP Total 17.90 Difference Between Proposed and ODP -0.13 Flow (Q): -1.27 Q = peak discharge (cfs) C = runoff coefficient I = rainfall intensity (in/hr) from IDF curve A = drainage area (acres) Area: Area: Area: RATIONAL METHOD PEAK RUNOFF (NEW IDF CURVE) Runoff for 2, 10 and 100 year storm events Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: COMPUTATIONS BY: JLB DATE: 11/18/2019 Basin Area (AC) C10 C100 Tc10 (min) Tc100 (min) Q10 (cfs) Q100 (cfs) 9 1.43 0.82 1.00 8.0 6.9 4.8 12.6 10 0.75 0.82 1.00 5.0 5.0 3 7.4 17 1.80 0.83 1.00 7.0 5.0 6.4 17.9 Drainage Summary Table From ODP RATIONAL METHOD PEAK RUNOFF (NEW IDF CURVE) Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 Runoff for 2, 10 and 100 year storm events Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 COMPUTATIONS BY: JLB DATE: 1/7/2020 Mannings Coefficient Area of Pipe Perimeter of Pipe Hydraulic Radius Slope Velocity Full Pipe Flow Full Pipe Flow PIPE From Invert US Pipe Size Length Invert DS Pipe Size To Pipe Slope n A (sf) P (ft) R(ft) S (ft/ft) V(ft/s) Q (cfs) Q (gpm) 9B Inlet 9B to Pipe 9A 4940.59 10 90 4939.60 12 9A 1.10% 0.015 0.55 2.62 0.21 0.011 3.66 2.00 896 9A 9A to Inlet 9 4939.60 12 32 4938.88 12 IN 9 2.25% 0.015 0.79 3.14 0.25 0.023 5.91 4.64 2,084 9 Inlet 9A to Inlet 9D 4938.84 12 55 4937.38 12 IN 9D 2.65% 0.015 0.79 3.14 0.25 0.027 6.42 5.04 2,264 10A 10A to Inlet 10 4941.95 8 65 4939.59 10 IN 10 3.63% 0.015 0.35 2.09 0.17 0.036 5.73 2.00 898 10B 10B to Inlet 10 4943.00 6 67 4939.59 10 IN 10 5.09% 0.015 0.20 1.57 0.13 0.051 5.60 1.10 494 10 Inlet 10 to MH 10 4939.55 12 105 4937.33 12 MH 10 2.11% 0.015 0.79 3.14 0.25 0.021 5.73 4.50 2,020 17B MH17B to MH17 4941.72 10 37 4940.61 12 MH17 3.00% 0.015 0.55 2.62 0.21 0.030 6.05 3.30 1,480 17A 17A to MH17 4941.04 8 15 4940.59 15 MH17 3.00% 0.015 0.35 2.09 0.17 0.030 5.21 1.82 816 17 MH17 to Inlet 17 4940.57 15 49 4939.83 24 IN17 1.51% 0.015 1.23 3.93 0.31 0.015 5.62 6.90 3,096 Basin No. Inlet Area (acres) C Qreq (10) Qavail(10) Qavail(100) 9A 9A 0.09 0.00 0.30 1.1 1.7 9B 9B 0.16 0.00 0.40 1.1 1.7 10 10B 0.21 0.00 0.60 1.1 2.1 17 17 0.19 0.00 0.50 0.6 1.7 Type 13 Valley Grate Type 13 Valley Grate Type 13 Valley Grate Type R Storm Pipe and Inlet Design Calculations PROPOSED CONDITIONS PROPOSED CONDITIONS OPERATIONAL FLOW CALCULATIONS PIPE SEGMENT DATA Type 10'' 10'' 10'' 10'' 10'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 10'' 10'' 10'' 10'' 10'' 12'' 12'' 8'' 8'' 8'' 8'' 8'' 8'' 8'' 8'' 6'' 8'' 8'' 8'' 8'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 12'' 12'' 12'' 12'' 12'' 12'' 12'' 12'' 12'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' X X X X X X X X X X X X X X X X X II I I II III I I I III I II Appendix B Impervious Area Comparison 10'' 10'' 10'' 10'' 10'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 10'' 10'' 10'' 10'' 10'' 12'' 12'' 8'' 8'' 8'' 8'' 8'' 8'' 8'' 8'' 6'' 8'' 8'' 8'' 8'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 12'' 12'' 12'' 12'' 12'' 12'' 12'' 12'' 12'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' X X X X X X X X X X X X X X X X X II I I II III I I I III I II This unofficial copy was downloaded on Jul-11-2015 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact Engineering Office 281 North College Fort Collins, CO 80521 USA impervious 71,649 SF pervious 15,894 SF 2,251 sf 24,694 sf 4,042 sf 1,526 sf 201 sf 1,498 sf 1,833 sf 196 sf 260 sf 75 sf 179 sf 65 sf 224 sf 502 sf 245 sf 614 sf 614 sf 640 sf 1,450 sf 81 sf 654 sf 2,329 sf 313 sf 574 sf 160 sf 7,115 sf 3,434 sf 87,602 sf 197 sf 305 sf 3,477 sf 2,413 sf 1,736 sf 124 sf 1,151 sf 208 sf 764 sf 86 sf 3,765 sf 1,726 sf 15,903 sf Appendix C Erosion Control Report TIMBERLINE CENER LOTS 4, 6, 7 PROJECT ECR Page 1 of 4 APPENDIX C – EROSION CONTROL REPORT A. Proposed Construction Area i. Developed Conditions – The proposed site is located at the northeast corner of the Joseph Allen Drive and Bear Mountain Drive, west of S. Timberline Rd., in Fort Collins. Currently, the proposed site development area route flows to two established detention ponds. One pond is on the northwest side of the site, and located to the east of the site. Vegetative Cover has been established in the detention ponds. ii. Rainfall Erodibility – Rainfall erosion will be controlled through use of temporary construction BMPs until permanent vegetative cover has reached 70% percent of groundcover. Opportunities for rainfall erosion include sheet flow across the site during earthwork operations and utility installations. iii. Proposed Rainfall Erosion and Sediment Control Methods – Primary methods will include silt fence installation on the east, west, north and south lot limits and inlet and channel protection with gravel bags to both slow and filter runoff water before it enters any structures or channel outletting to the detention pond. A stabilized construction entrance will be utilized at the site ingress/egress point. iv. Site Phasing and BMP Installation Schedule – The site construction will take place in the following order: 1. Installation of site BMPs i. Stabilized Construction Entrance ii. Silt Fence iii. Inlet protection on existing inlets 2. Site Utility Installation i. Installation of inlet control in new inlets and channels as they are finished 3. Building Foundation and Earthwork 4. Vertical building construction and ongoing utilities 5. Finished site grading, hardscaping and paving 6. Landscaping and Irrigation installation B. Stormwater Management Controls i. SWMP Administrator 1. During construction, the SWMP administrator will be the earthwork and utility contractor. Until such time as that contractor has been selected, the SWMP Administrator will be Keith Meyer, Project Manager-Ditesco. He will be TIMBERLINE CENER LOTS 4, 6, 7 PROJECT ECR Page 2 of 4 responsible for developing, implementing, maintaining, and revising the SWMP and will address all aspects of the site SWMP. i. Keith Meyer, PE – Ditesco Project Manager 2133 S. Timberline Rd, Suite 110 Fort Collins, CO 80525 (970)988-8605 ii. Identification of Potential Pollution Sources 1. All disturbed and stored soils – there will be disturbed soils onsite through excavation and vehicle/equipment movement. Soils will be stockpiled/permanently embanked onsite. Excess soil will be transported offsite. Soil stockpiles left undisturbed for a period greater than 30 days will be mulched and seeded. 2. Vehicle tracking of sediments – most vehicle and equipment travel will risk sediment tracking until final pavement is installed. A stabilized construction entrance will be used for the site. Surrounding roadways will be swept if sediment is tracked onto the roadway. 3. Management of contaminated soils – soils may be contaminated through spills during fueling operation or equipment oil leaks. The contractor will keep spill kits onsite during the project and will excavate and remove contaminated kit materials and soil and dispose through the proper waste stream. 4. Loading and unloading operations – Loading and unloading operations will take place within the site for materials to be incorporated in the project. Vehicles will use the stabilized entrance for ingress/egress. 5. Outdoor storage activities (building materials, fertilizers, chemicals, etc.) Storage of materials will be in a designated area. Any chemicals used during construction, concrete cure, etc., will be stored on secondary containment. 6. Vehicle and equipment maintenance and fueling – Maintenance and fueling will be done in the field at the location of the equipment on grade. Spills will be addressed through item 3 of this section. 7. Significant dust or particulate generating processes – dust may be generated from vehicle tracking or portions of backfill operation. The site will be kept from producing dust through watering of any exposed soils. 8. Routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, oils, etc. – Fueling, lubrication, and maintenance operations will take place within the project limits on grade. No fertilizers pesticides or detergents are planned for use on site. 9. On-site waste management practices (waste piles, liquid wastes, dumpsters, etc.) Roll-off Dumpsters will be utilized for the site and will be hauled off at TIMBERLINE CENER LOTS 4, 6, 7 PROJECT ECR Page 3 of 4 regular intervals. Any liquid waste generated will be contained. Concrete process water will be addressed through the next item in the section. 10. Concrete truck/equipment washing, including the concrete truck chute and associated fixtures and equipment – A concrete wash out will be utilized for all concrete placement operations. A sign will be posted clearly showing the washout location. 11. Dedicated asphalt and concrete batch plants – no asphalt or concrete batch plants will be erected onsite. 12. Non-industrial waste sources such as worker trash and portable toilets – Portable toilets will be staged onsite. Trash receptacles will be emptied regularly. 13. Other areas or procedures where potential spills can occur – No other areas qualify for this section. C. Dryland Vegetation i. PLACEHOLDER – soil types, seed mix, soil amendments, mulches D. Detailed Sequence of Construction Activities i. It is anticipated that this project will begin construction during 2020 and will be completed within a year. ii. Installation of site BMPs 1. Stabilized Construction Entrance 2. Silt Fence 3. Inlet protection on existing inlets iii. Site Utility Installation 1. Installation of drainage facilities 2. Installation of inlet control/BMPs in new inlets and channels as they are finished iv. Building Foundation and Earthwork v. Vertical building construction and ongoing utilities vi. Finished site grading, hardscaping and paving vii. Landscaping and Irrigation installation 1. Seeding and mulching 2. Tree planting 3. Shrub planting viii. Vegetative cover establishment period ix. Removal of silt fence and inlet protection x. BMPs will be inspected for effectiveness and maintained after each runoff event and every 14 days at a minimum during construction. E. Erosion Control Security Calculations TIMBERLINE CENER LOTS 4, 6, 7 PROJECT ECR Page 4 of 4 Example Erosion and Sediment Control Escrow/Security Calculation for The City of Fort Collins Project: Timberline Lots 4, 6, 7 Disturbed Acres: 2.0 BMP Amount EROSION CONTROL BMPS Units Estimated Quantity Unit Price Total Price Silt Fence (SF) LF 1280 $2.50 $3,200.00 Inlet Protection (IP) EA 2 $150.00 $300.00 Concrete Washout (CW) EA 1 $928.00 $928.00 Vehicle Tracking Control (VTC) EA 1 $1,750.00 $1,750.00 (add all other BMPs for the site in this list) SubTotal: $6,178.00 1.5 x Sub-Total: $9,267.00 Amount of security: $9,267.00 Minimum Escrow Amount Minimum escrow amount: $3,000.00 Final Escrow Amount Erosion Control Escrow: $9,267.00 Appendix D LID Calculations 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 10'' 10'' 10'' 10'' 10'' 8'' 8'' 8'' 8'' 8'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 8'' 8'' 6'' 6'' 6'' 8'' 6'' 6'' 6'' 6'' 6'' 10'' 10'' 10'' 10'' 6'' 10'' 10'' 8'' 8'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' 6'' X X X X X X X X X X X X X X X X X II II I I III I I I III I II C Gas Irrigation Control D MW Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: COMPUTATIONS BY: JLB/KM DATE: 12/26/2019 Area Description Color Area-SF Asphalt Grey 27,970 Sidewalks Peach 7,770 Curb/Gutter Orange 2,300 Building Footprint Yellow 26,390 Total Area 64,430 Area Description Color Area-SF Landscaping Beds Green 15,235 Porous Pavers Blue 8,580 Total Area 23,815 73.0% Paver Area (sf) Max (3:1) Runon Area (sf) Actual Treated Area (sf) Paver Area 1 1190 3570 965 2155 Paver Area 2 1200 3600 3377 4577 Paver Area 3 851 2553 5548 3404 Paver Area 4 1115 3345 3468 4460 Paver Area 5 930 2790 563 1493 Paver Area 6 1495 4485 1727 3222 Paver Area 7 730 2190 119 849 Paver Area 8 885 2655 452 1337 Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 LID Summary for Lofts Project Timberline Lots 4,6,7 (proposed Lofts project) Impervious Area Summary Pervious Area Summary Impervious Percentage Ditesco 2133 S. Timberline Rd. Suite 110 Fort Collins, CO 80525 LOCATION: COMPUTATIONS BY: JLB/KM DATE: 12/26/2019 25% of new paved areas must be pervious; Area (sf) Area (ac) Total new Impervious 64,430 1.48 Required area to be treated 32,215 0.74 Actual area being treated by pavers 21,497 0.49 Actual area being treated by rain garden 8,235 0.19 Difference 2,483 0.06 Percent being treated 46.1% 46.1% New Pavement Area 38,040 0.87 Required Min. Area of Permeable Pavers 9,510 0.22 Actual Area of Permeable Pavers 8,580 0.20 Difference 930 0.02 Percentage 22.6% 22.6% Or Total new Impervious 64,430 Required area to be treated 48,323 Actual area being treated 29,732 Difference 18,591 Percent being treated 46% 50% of the newly added or modified impervious area must be treated by LID techniques and treat 75% of all newly added or modified impervious area must be treated by LID techniques LID Summary for Lofts Project Timberline Center - Revised for Lofts at Timberline, Lots 4, 6 and 7 Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia = 100.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 1.000 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.40 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area) Area = 8,207 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = 0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER = 273.6 cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum) DWQCV = 12 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 0.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin = 164 sq ft D) Actual Flat Surface Area AActual = 175 sq ft E) Area at Design Depth (Top Surface Area) ATop = 175 sq ft F) Rain Garden Total Volume VT= 175 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 25" provided 4. Underdrain System A) Are underdrains provided? B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y = 1.4 ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 = 274 cu ft iii) Orifice Diameter, 3/8" Minimum DO = 2/5 in Design Procedure Form: Rain Garden (RG) Keith Meyer Ditesco January 30, 2020 Lofts at Timberline Raingarden at west entrance Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO UD - Rain Garden, RG 2/6/2020, 4:25 PM Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation A) Will the rain garden be irrigated? Notes: 1. Side slopes of rain garden to be installed at 4:1 Design Procedure Form: Rain Garden (RG) Keith Meyer Ditesco January 30, 2020 Lofts at Timberline Raingarden at west entrance Choose One Choose One Choose One Sheet Flow- No Energy Dissipation Required Concentrated Flow- Energy Dissipation Provided Plantings Seed (Plan for frequent weed control) Sand Grown or Other High Infiltration Sod Choose One YES NO YES NO UD - Rain Garden, RG 2/6/2020, 4:25 PM Appendix E Overall Drainage Basin Comparison 1 2 3 4 A B C D E F G H I 5 6 7 8 9 10 Fire Riser DW Entry LS Backflow C.8 C.1 C.9 D.9 E.8 J Possible Entry Point Possible Entry Point Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Possible Entry Point TF Joseph Allen Drive Bear Mountain Drive S. Timberline Road Nancy Gray Avenue 9 10 17 Drawing Name: D:\Projects\Lofts At Timberline\Dwg\Exhibits\Original Basin Monday, Boundry.February dwg 03, 2:2020 46 PM By: Rhonda Bunner LOFTS AT TIMBERLINE ORIGINAL DRAINAGE BASINS SCALE: 1" =60' 60' 0 60' 120' 180' (True scale for 22x34 sheet size) BASIN ID OLD AREA NEW AREA DELTA 9 1.43 AC 1.88 AC +0.45 10 0.75 AC 0.42 AC -0.33 17 1.80 AC 1.67 AC -0.13 1 2 3 4 A B C D E F G H I 5 6 7 8 9 10 Fire Riser DW Entry LS Backflow C.8 C.1 C.9 D.9 E.8 J Possible Entry Point Possible Entry Point Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Possible Entry Point TF Joseph Allen Drive Bear Mountain Drive S. Timberline Road Nancy Gray Avenue 10 9 17 LOFTS AT TIMBERLINE PROPOSED DRAINAGE BASINS SCALE: 1" =60' 60' 0 60' 120' 180' (True scale for 22x34 sheet size) Drawing Name: D:\Projects\Lofts At Timberline\Dwg\Exhibits\Proposed Monday, Basin Boundry.February dwg 03, 2:2020 01 PM By: Rhonda Bunner BASIN ID OLD AREA NEW AREA DELTA 9 1.43 AC 1.88 AC +0.45 10 0.75 AC 0.42 AC -0.33 17 1.80 AC 1.67 AC -0.13 C CC CC MW W V W V W V W V W V W V W V W V W V W V W M D D D D D D M W V W C S Irrigation Control T C Electric Vault Electric Vault Irrigation Control Irrigation Control Irrigation Control CC Gas Electric T T C C H Y D D D D D D H Y D Electric Vault 1 2 3 4 A B C D E F G H I 5 6 7 8 9 10 F ire Riser DW Entry LS Backflow C.8 C.1 C.9 D.9 E.8 J Possible Entry Point Possible Entry Point Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Possible Entry Point TF LOT 4 TIMBERLINE CENTER LOT 6 TIMBERLINE CENTER LOT 7 TIMBERLINE CENTER Joseph Allen Drive Bear Mountain Drive FFE=4947.600 CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. Call before you dig. R SHEET NO. x PROJECT NO. SHEET INDEX DESIGNED BY: DRAWN BY: APPROVED BY: SCALE: SHEET SUBSET: LOT 4, LOT 6, LOT 7, TIMBERLINE CENTER, THIRD FILING DATE: NONE November 19, 2019 K. Meyer Drawing Name: D:\Projects\Lofts At Timberline\Dwg\Sheets\Timberline Thursday, Lofts-Grading.December dwg 05, 5:2019 50 AM By: Rhonda Bunner R. Bunner K. Meyer NOT FOR CONSTRUCTION REVIEW SET City of Fort Collins, Colorado UTILITY PLAN APPROVAL Date Date Date Date Date Date City Engineer Traffic Engineer Parks & Recreation Stormwater Utility Water & Wastewater Utility SCALE: 1" =20' 0 (True scale for 22x34 sheet size) 20' 20' 40' 60' C401 4 OVERALL GRADING PLAN 1" = 20' LEGEND: 10'' NOTES: 965 sf Paver Area 1 = 1,188 sf Paver Area 2 = 1,200 sf 3,377 sf Paver Area 3 = 851 sf 5,548 sf Paver Area 4 = 1,115 sf 3,468 sf Paver Area 5 = 930 sf 563 sf Paver Area 6 = 1,495 sf 1,727 sf Paver Area 7 = 730 sf 119 sf Paver Area 8 = 885 sf 452 sf 162 sf C Gas Irrigation Control D MW C CC CC MW W V W V W V W V W V W V W V W V W V W V W M D D D D D D M W V W C S Irrigation Control T C Electric Vault Electric Vault Irrigation Control Irrigation Control Irrigation Control W CC Gas Electric T T C C H Y D D D D D D H Y D Electric Vault 1 2 3 4 A B C D E F G H I 5 6 7 8 9 10 F ire Riser DW Entry LS Backflow C.8 C.1 C.9 D.9 E.8 J Possible Entry Point Possible Entry Point Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Possible Entry Point LOT 4 TIMBERLINE CENTER THIRD FILING LOT 6 TIMBERLINE CENTER THIRD FILING LOT 7 TIMBERLINE CENTER THIRD FILING Joseph Allen Drive Bear Mountain Drive CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. Call before you dig. R SHEET NO. x PROJECT NO. SHEET INDEX DESIGNED BY: DRAWN BY: APPROVED BY: SCALE: SHEET SUBSET: LOT 4, LOT 6, LOT 7, TIMBERLINE CENTER, THIRD FILING DATE: NONE October 31, 2019 K. Meyer Drawing Name: D:\Projects\Lofts At Timberline\Dwg\Sheets\Timberline Thursday, Lofts-Drainage.October dwg 31, 9:2019 17 AM By: Rhonda Bunner R. Bunner K. Meyer NOT FOR CONSTRUCTION REVIEW SET City of Fort Collins, Colorado UTILITY PLAN APPROVAL Date Date Date Date Date Date City Engineer Traffic Engineer Parks & Recreation Stormwater Utility Water & Wastewater Utility SCALE: 1" =20' 0 (True scale for 22x34 sheet size) 20' 20' 40' 60' C801 6 DEVELOPED DRAINAGE EXHIBIT 1" = 20' LEGEND: NOTES: A FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION 5,880 sf 307 sf 6,660 sf 16,350 sf 10,604 sf 2,034 sf 125 sf 102 sf 102 sf 100 sf 539 sf 184 sf 124 sf 910 sf 2,093 sf 1,840 sf 444 sf 373 sf 38 sf 43 sf 6,880 sf 627 sf 54 sf 790 sf 110 sf 28 sf 120 sf 270 sf 157 sf 542 sf 1,185 sf 928 sf 900 sf 1,494 sf 731 sf 884 sf 110 sf 1,201 sf 1,188 sf 246 sf 2,090 sf 933 sf 89 sf 32 sf 115 sf 115 sf 132 sf 112 sf 5,587 sf 150 sf 235 sf 7 sf 2,219 sf 65 sf 119 sf 114 sf 105 sf 101 sf 94 sf 1,925 sf 2,801 sf 153 sf 221 sf 982 sf 1,164 sf 568 sf 558 sf 187 sf 17 10 9 747 sf C Gas Irrigation Control D MW C CC CC MW W V W V W V W V W V W V W V W V W V W V W M D D D D D D M W V W C S Irrigation Control T C Electric Vault Electric Vault Irrigation Control Irrigation Control Irrigation Control W CC Gas Electric T T C C H Y D D D D D D H Y D Electric Vault 1 2 3 4 A B C D E F G H I 5 6 7 8 9 10 F ire Riser DW Entry LS Backflow C.8 C.1 C.9 D.9 E.8 J Possible Entry Point Possible Entry Point Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Overhead Door Possible Entry Point LOT 4 TIMBERLINE CENTER THIRD FILING LOT 6 TIMBERLINE CENTER THIRD FILING LOT 7 TIMBERLINE CENTER THIRD FILING Joseph Allen Drive Bear Mountain Drive CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. Call before you dig. R SHEET NO. x PROJECT NO. SHEET INDEX DESIGNED BY: DRAWN BY: APPROVED BY: SCALE: SHEET SUBSET: LOT 4, LOT 6, LOT 7, TIMBERLINE CENTER, THIRD FILING DATE: NONE October 31, 2019 K. Meyer Drawing Name: D:\Projects\Lofts At Timberline\Dwg\Sheets\Timberline Thursday, Lofts-Drainage.October dwg 31, 9:2019 17 AM By: Rhonda Bunner R. Bunner K. Meyer NOT FOR CONSTRUCTION REVIEW SET City of Fort Collins, Colorado UTILITY PLAN APPROVAL Date Date Date Date Date Date City Engineer Traffic Engineer Parks & Recreation Stormwater Utility Water & Wastewater Utility SCALE: 1" =20' 0 (True scale for 22x34 sheet size) 20' 20' 40' 60' C801 6 DEVELOPED DRAINAGE EXHIBIT 1" = 20' LEGEND: NOTES: A FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION 219 sf 151 sf 1,536 sf 1,494 sf 6,049 sf 2,429 sf 928 sf 6,880 sf 731 sf 2,848 sf 1,899 sf 105 sf 114 sf 1,925 sf 101 sf 2,149 sf 6,663 sf 10,063 sf 2,119 sf 982 sf 1,185 sf 856 sf 398 sf 219 sf 246 sf 6,289 sf 1,188 sf 1,201 sf 9A 10C 10B 10 10A 10AA 10AB 10AC 10AD 17 17B 17A 17BA 17BC 306 sf 8,306 sf 125 sf 102 sf 102 sf 100 sf 184 sf 124 sf 885 sf 1,609 sf 444 sf 394 sf 16 sf 17 sf 54 sf 799 sf 110 sf 28 sf 120 sf 270 sf 157 sf 522 sf 884 sf 110 sf 68 sf 803 sf 49 sf 32 sf 115 sf 115 sf 132 sf 112 sf 173 sf 104 sf 7 sf 2,241 sf 65 sf 119 sf 94 sf 153 sf 221 sf 1,164 sf 503 sf 351 sf 170 sf 17 9 747 sf 9AA 9AB 9AC 9AD 9AE 9AF 9BA 9C 9BB 9 9E 9ED 9EC 9EB 9EA 17BB 17BD 17BDB 17BDA 17BCA 17BCB 17AA 17AB 17AC 17AD 17AE 17AF 17 9B 76 sf 124 sf 150 sf 122 sf 123 sf 123 sf 133 sf 110 sf 35 sf 472 sf 2,371 sf 561 sf 61 sf 17 sf 195 sf 17 sf 15 sf 2 sf 40 ft 100 ft 37 ft 200 ft 58 ft 232 ft 30 ft 48 ft 20 ft 90 ft 139 ft 37 ft 121 ft 14 ft 31 ft 163 ft 25 ft 140 ft 6 ft 11 ft 25 ft 192 ft 2 ft 14 ft 25 ft 5 ft 5 ft 31 ft 12 ft 78 ft 15 ft 9B 57 ft 90 ft 9A 28 ft 27 ft 27 ft 23 ft 20 ft 26 ft 32 ft 54 ft 55 ft Inlet 9D INV OUT = 4939.57 INV IN = 4937.38 (S) INV OUT = 4937.33(W) INV IN = 4941.21 (E) INV IN = 4938.40(S) INV OUT = 4938.34 (N) Inlet 17 INV OUT = 4939.79 (N) Inlet 9B MH 9E MH 10 Inlet 10 Inlet 9 36 ft Inlet 9E 24 ft 20 ft 105 ft 56 ft 67 ft 65 ft 23 ft 37 ft 35 ft 11 ft 15 ft 8 ft 18 ft 32 ft 28 ft 30 ft 26 ft 37 ft 66 ft MH17A MH17B 60 ft Inlet 17A 16 ft 3 ft 73 ft 57 ft 48 ft 27 ft 27 ft 10B 10 53'-0" 163'-8 3/4" �� �.��