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HomeMy WebLinkAboutWPO201800007 Calculations 2018-04-16BLOSSOM CONSULTING & ENGINEERING RIVANNA VILLAGE — AMENDMENT 1 AND PHASE II Stormwater Management Plan — Supplemental Calculations WPO201800007 Albemarle County, Virginia Date: March 2, 2018 Revised: April 16, 2018 Prepared for: County of Albemarle Department of Community Development 401 Mchitire Road, Room 227 Charlottesville, VA 22902-4596 c/o Mr. Bobby Jocz Prepared by: Blossom Consulting and Engineering, Inc. 1101 Professional Drive, Suite G Williamsburg, Virginia23185 (757)870-4825 scott9blossomconsulting.net APPROVED by the Albemarle County Community Development Department Date 05/09/2018 File WP0201800007 Rivanna Village — Amendment t and Phase II Stormwater Management Plan — Supplemental Calculations INTRODUCTION As requested by the Robinson Development Group (RDG) (Client), Blossom Consulting and Engineering, Inc. (BCE) prepared a Stormwater Management Plan, an Erosion and Sediment Control Plan, and a Buffer Mitigation Plan for Phase II of the Rivanna Village development, including amendments to a portion of the previously submitted Phase I plans. This calculations booklet is being provided in response to comments received from Albemarle County dated January 17, 2018 for the project (WP02Oi800007). This report includes supplemental stormwater and erosion and sediment control calculations and design information for the project. Routing of proposed BMPs was completed in Bentley Systems Inc. (Haested Method's) Pond Pack software, which uses TR-55 methodology and level pool routing with detailed outfall structure definitions. Principle and emergency spillways associated with the proposed BMPs were routed to calculate pre and post development peak flow rates, volumes and associated water surface elevations. Hydrograph volumes and associated peak flow rates are provided for modelled drainage areas and hydrologic node locations shown on Sheets SWM- 23 and SWM-24. As required by Virginia State stormwater regulations, water quality calculations were completed using the Virginia Runoff Reduction Methodology (VRRM). Associated VRRM calculations are provided herein. VRRM calculations were completed for the entire site area (9o.6 acres) and include previously approved Phase I BMPs as well as proposed Phase II BMPs. In addition, as requested by Albemarle County, an example Maintenance Agreement and Deed Restriction is provided. Proposed BMP Maintenance Easements and Forest/Open Space Easements are depicted on Sheet SWM-25. Easements and associated restrictive covenants shall be recorded prior to plan approval. Specifically, this report includes the following: • Appendix A: Pondpack Master Network Summary o Pre -Development o Post -Development • AppendixB: BMP Stage -Storage • Appendix C: VRRM Spreadsheets • Appendix D: Erosion and Sediment Control Data o Outlet Structure Data (SBh and SBI2) o ESC facility Routing Summary (SBh and SBI2) 0 Appendix E: Example Deed restriction and Maintenance Agreements Rivanna Village — Amendment t and Phase II Stormwater Management Plan — Supplemental Calculations Appendix A — Pond Pack Master Network Summary (Pre -Development) 2 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (ft3/s) (years) (ac-ft) 4A Post -Development 1- 1 2.712 12.040 41.56 4A Post R -Development 2- 2 3.880 12.020 60.34 4A Post -Development 10 10 7.735 12.010 121.18 4A Post -Development 25 25 10.527 12.010 164.16 4A Post -Development 100 15.799 12.010 243.18 100-YR 5 Post R -Development 1- 1 2.107 12.140 23.87 5 Post R -Development 2- 2 3.070 12.140 35.84 5 Post -Development 10 10 6.300 12.100 75.76 5 Post -Development 25 25 8.668 12.100 104.58 5 Post -Development 100 13.170 12.100 158.24 100-YR 48 Post R -Development 1- 1 0.587 12.070 7.44 48 Post R -Development 2- 2 0.883 12.070 11.76 48 Post -Development 10 10 1.903 12.060 26.39 48 Post -Development 25 25 2.666 12.060 37.13 48 Post -Development 100 4.134 12.060 57.35 100-YR 38 Post R -Development 1- 1 0.778 12.050 11.50 38 Post R -Development 2- 2 1.126 12.030 16.93 38 Post -Development 10 10 2.285 12.020 34.82 38 Post -Development 25 25 3.130 12.020 47.58 38 Post -Development 100 4.733 12.020 71.18 100-YR 3A Post R -Development 1- 1 1.998 12.040 29.37 3A Post R -Development 2- 2 2.970 12.030 44.97 3A Post -Development 10 10 6.286 12.010 97.29 3A Post -Development 25 25 8.747 12.010 135.67 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_ph2swm_PRE _20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 1 of 5 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/s) (years) (ac-ft) 3A Post -Development 100 13.465 12.010 207.50 100-YR 2 Post R -Development 1- 1 2.632 12.020 39.97 2 Post R -Development 2- 2 3.841 12.020 59.79 2 Post -Development 10 10 7.900 12.020 124.61 2 Post -Development 25 25 10.878 12.020 170.86 2 Post -Development 100 16.545 12.020 256.52 100-YR 1 Post R -Development 1- 1 1.303 12.050 18.26 1 Post R -Development 2- 2 1.944 12.050 28.26 1 Post -Development 10 10 4.139 12.030 61.72 1 Post -Development 25 25 5.773 12.030 86.29 1 Post -Development 100 8.910 12.020 132.37 100-YR 6 Post R -Development 1- 1 0.504 12.040 7.57 6 Post R -Development 2- 2 0.752 12.020 11.66 6 Post -Development 10 10 1.600 12.020 25.38 6 Post -Development 25 25 2.231 12.010 35.33 6 Post -Development 100 3.441 12.010 54.03 100-YR 7 Post R -Development 1- 1 0.570 12.100 7.12 7 Post R -Development 2- 2 0.859 12.070 11.20 7 Post -Development 10 10 1.857 12.060 25.39 7 Post -Development 25 25 2.604 12.060 35.82 7 Post -Development 100 4.043 12.060 55.48 100-YR A Post R -Development 1- 1 0.205 12.080 2.68 A Post R -Development 2- 2 0.297 12.070 3.99 A Post -Development 10 10 0.605 12.070 8.28 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Val 005_ph2swrn_PRE _20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 2 of 5 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/s) (years) (ac-ft) A Post -Development 25 25 0.830 12.070 11.34 A Post -Development 100 1.256 12.070 17.01 100-YR Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/s) (years) (ac-ft) OUT Post R -Development 1- 1 13.396 12.040 184.48 OUT Post R -Development 2- 2 19.622 12.040 278.21 OUT Post -Development 10 10 40.608 12.030 586.81 OUT Post -Development 25 25 56.055 12.030 809.37 OUT Post -Development 100 85.497 12.020 1,225.14 100-YR J-4A Post R -Development 1- 1 2.712 12.040 41.56 J-4A Post R -Development 2- 2 3.880 12.020 60.34 J-4A Post -Development 10 10 7.735 12.010 121.18 J-4A Post -Development 25 25 10.527 12.010 164.16 J-4A Post -Development 100 15.799 12.010 243.18 100-YR J 38 Post R -Development 1- 1 0.778 12.050 11.50 J-38 Post R -Development 2- 2 1.126 12.030 16.93 J 38 Post -Development 10 10 2.285 12.020 34.82 J-38 Post -Development 25 25 3.130 12.020 47.58 J-38 Post -Development 100 4.733 12.020 71.18 100-YR J 5 Post R -Development 1- 1 2.107 12.140 23.87 J 5 Post R -Development 2- 2 3.070 12.140 35.84 3-5 Post -Development 10 10 6.300 12.100 75.76 J 5 Post -Development 25 25 8.668 12.100 104.58 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Val 005_ph2swm_PRE _20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 3 of 5 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/S) (years) (ac-ft) J-5 Post -Development 100 13.170 12.100 158.24 100-YR 6 Post R -Development 1- 1 0.504 12.040 7.57 6 Post R -Development 2- 2 0.752 12.020 11.66 J-6 Post -Development 10 10 1.600 12.020 25.38 J-6 Post -Development 25 25 2.231 12.010 35.33 J-6 Post -Development 100 3.441 12.010 54.03 100-YR J-1 Post R -Development 1- 1 1.303 12.050 18.26 1 Post R -Development 2- 2 1.944 12.050 28.26 J-1 Post -Development 10 10 4.139 12.030 61.72 J-1 Post -Development 25 25 5.773 12.030 86.29 J-1 Post -Development 100 8.910 12.020 132.37 100-YR J-2 Post R -Development 1- 1 2.632 12.020 39.97 J-2 Post R -Development 2- 2 3.841 12.020 59.79 J-2 Post -Development 10 10 7.900 12.020 124.61 J-2 Post -Development 25 25 10.878 12.020 170.86 2 Post -Development 100 16.545 12.020 256.52 100-YR 3-A Post R -Development 1- 1 6.280 12.040 92.01 3-A Post R -Development 2- 2 9.156 12.040 137.11 3-A Post -Development 10 10 18.813 12.020 285.77 3-A Post -Development 25 25 25.900 12.020 392.66 3-A Post -Development 100 39.387 12.010 591.54 100-YR 3-413 Post R -Development 1- 1 3.299 12.040 48.63 3-413 Post R -Development 2- 2 4.763 12.040 71.40 3-413 Post -Development 10 10 9.638 12.020 145.88 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_ph2swrn_PRE _20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 4 of 5 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/S) (years) (ac-ft) 3-413 Post -Development 25 25 13.193 12.020 198.95 3-413 Post -Development 100 19.933 12.010 297.39 100-YR J 3A Post R -Development 1- 1 2.777 12.040 40.83 J 3A Post R -Development 2- 2 4.096 12.030 61.89 J 3A Post -Development 10 10 8.570 12.020 132.10 J 3A Post -Development 25 25 11.878 12.020 182.96 3-3A Post -Development 100 18.198 12.010 278.21 100-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_ph2swrn_PRE _20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 5 of 5 Watertown, CT 06795 USA +1-203-755-1666 Appendix A — Pond Pack Master Network Summary (Post -Development) Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (k3/s) (years) (ark) 1 Post -Development 1- 1 1.407 12.050 20.04 2 Post R -Development 1- 1 2.712 12.020 41.64 3A Post R -Development 1- 1 2.606 12.030 40.10 30 Post R -Development 1- 1 0.782 12.050 11.57 4A Post R -Development 1- 1 2.514 12.040 38.23 40 Post R -Development 1- 1 0.796 12.070 10.55 5 Post R -Development 1- 1 2.532 12.150 29.15 5A Post R -Development 1- 1 0.472 11.990 7.90 513 Post R -Development 1- 1 0.584 12.060 7.92 6 Post R -Development 1- 1 0.647 12.020 10.08 7 Post R -Development 1- 1 0.724 12.070 9.54 Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (k3/s) (years) (ark) 1 Post R -Development 1- 1 1.407 12.050 20.04 J-2 Post R -Development 1- 1 2.712 12.020 41.64 J-3A Post R -Development 1- 1 3.388 12.030 51.61 J 30 Post R -Development 1- 1 0.782 12.050 11.57 J-4A Post R -Development 1- 1 2.514 12.040 38.23 J-413 Post R -Development 1- 1 3.310 12.040 48.37 J 5 Post R -Development 1- 1 1.056 12.030 15.14 J 5A Post R -Development 1- 1 0.472 11.990 7.90 J 6 Post R -Development 1- 1 0.647 12.020 10.08 J-A Post R -Development 1- 1 8.092 12.420 34.17 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_1h2swm_POST_1vRrouted_20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 1 of 2 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Event (years) OUT YR -Development 1- 1 Pond Summary Label Scenario Return Hydrograph Event Volume (years) (ac-ft) Hydrograph Volume (ac-ft) 14.639 Time to Peak (hours) Time to Peak Peak Flow (hours) (ft3/S) 12.050 Peak Flow (fta/S) 102.71 Maximum Maximum Water Pond Storage Surface (ac-ft) Elevation (ft) Post- BMP Il (IN) Development 1 9.230 12.040 125.25 (N/A) (N/A) 1-YR BMP Il Post (DM Development 1 8.092 12.420 34.17 342.42 7.756 1-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Val 0051/h2swm_POST_1YRmuted_20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 2 of 2 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (k3/s) (years) (ark) 1 Post -Development 2- 2 2.094 12.050 30.71 2 Post R -Development 2- 2 4.041 12.020 63.37 3A Post R -Development 2- 2 3.705 12.010 57.35 38 Post R -Development 2- 2 1.131 12.030 17.00 4A Post R -Development 2- 2 3.643 12.020 56.35 48 Post R -Development 2- 2 1.199 12.070 16.40 5 Post R -Development 2- 2 3.445 12.150 39.77 5A Post R -Development 2- 2 0.667 11.980 11.26 513 Post R -Development 2- 2 0.896 12.060 12.57 6 Post R -Development 2- 2 0.927 12.020 14.64 7 Post R -Development 2- 2 1.041 12.060 14.08 Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (ka/s) (years) (ark) 1 Post R -Development 2- 2 2.094 12.050 30.71 J-2 Post R -Development 2- 2 4.041 12.020 63.37 J 3A Post R -Development 2- 2 4.836 12.030 74.35 J-38 Post R -Development 2- 2 1.131 12.030 17.00 J-4A Post R -Development 2- 2 3.643 12.020 56.35 J-413 Post R -Development 2- 2 4.842 12.040 72.20 J 5 Post R -Development 2- 2 1.563 12.020 22.87 J 5A Post R -Development 2- 2 0.667 11.980 11.26 J 6 Post R -Development 2- 2 0.927 12.020 14.64 J-A Post R -Development 2- 2 11.793 12.250 84.17 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_1h2swm_POST_2vRrouted_20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 1 of 2 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Event (years) OUT YR -Development 2- 2 Pond Summary Label Scenario Return Hydrograph Event Volume (years) (ac-ft) Hydrograph Volume (ac-ft) 21.459 Time to Peak (hours) Time to Peak Peak Flow (hours) (ft3/S) 12.100 Peak Flow (fta/S) 171.92 Maximum Maximum Water Pond Storage Surface (ac-ft) Elevation (ft) Post- BMP Il (IN) Development 2 13.123 12.040 181.38 (N/A) (N/A) 2-YR BMP Il Post (DM Development 2 11.793 12.250 84.17 342.90 8.637 2-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Val 0051/h2swm_POST_2YRmuted_20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 2 of 2 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (k3/s) (years) (ark) 1 PyoR -Development 10 10 4.419 12.030 66.03 2 Post -Development 10 10 8.312 12.020 130.74 3A Post -Development 10 10 7.197 12.010 111.08 38 Post -Development 10 10 2.290 12.020 34.90 4A Post -Development 10 10 7.411 12.010 116.17 48 Post -Development 10 10 2.515 12.060 35.03 5 Post -Development 10 10 6.320 12.100 72.37 5A Post -Development 10 10 1.302 11.970 22.01 513 Post -Development 10 10 1.899 12.060 27.04 6 Post -Development 10 10 1.849 12.010 29.27 7 Post -Development 10 10 2.093 12.060 28.80 Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (ka/s) (years) (ark) 1 Post -Development 10 10 4.419 12.030 66.03 J-2 Post -Development 10 10 8.312 12.020 130.74 J 3A Post -Development 10 10 9.487 12.010 145.61 J-38 Post -Development 10 10 2.290 12.020 34.90 J-4A Post -Development 10 10 7.411 12.010 116.17 J-413 Post -Development 10 10 9.926 12.020 149.52 J 5 Post -Development 10 10 3.201 12.020 47.15 J 5A Post -Development 10 10 1.302 11.970 22.01 J 6 Post -Development 10 10 1.849 12.010 29.27 J-A Post -Development 10 10 23.853 12.140 271.08 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_ph2swm_POST_10VRrouted_20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 1 of 2 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Event (years) R -Development 10 OUT P 10 Pond Summary Label Scenario Return Hydrograph Event Volume (years) (ac-ft) Hydrograph Volume (ac-ft) 43.727 Time to Peak (hours) Time to Peak Peak Flow (hours) (ft3/S) 12.070 Peak Flow (fta/S) 526.30 Maximum Maximum Water Pond Storage Surface (ac-ft) Elevation (ft) Post- BMP Il (IN) Development 10 25.733 12.040 358.31 (N/A) (N/A) 10-YR BMP Il Post (DM Development 10 23.853 12.140 271.08 344.02 10.817 10-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_ph2swm_POST_10YRrouted_20171110.ppc Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 2 of 2 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/s) (years) (ac-ft) 4A Post -Development 1- 1 2.516 12.040 38.27 4A Post R -Development 2- 2 3.646 12.020 56.41 4A Post -Development 10 10 7.416 12.010 116.25 4A Post -Development 25 25 10.170 12.010 158.95 4A Post -Development 100 15.393 12.010 237.91 100-YR 5 Post R -Development 1- 1 2.532 12.150 29.15 5 Post R -Development 2- 2 3.445 12.150 39.77 5 Post -Development 10 10 6.320 12.100 72.37 5 Post -Development 25 25 8.337 12.100 94.88 5 Post -Development 100 12.071 12.100 135.61 100-YR 5A Post R -Development 1- 1 0.472 11.990 7.90 5A Post R -Development 2- 2 0.667 11.980 11.26 5A Post -Development 10 10 1.302 11.970 22.01 5A Post -Development 25 25 1.758 11.970 29.51 5A Post -Development 100 2.614 11.970 43.24 100-YR 48 Post R -Development 1- 1 1.001 12.070 13.71 48 Post R -Development 2- 2 1.406 12.060 19.49 48 Post -Development 10 10 2.721 12.060 37.83 48 Post -Development 25 25 3.662 12.060 50.60 48 Post -Development 100 5.426 12.060 73.92 100-YR 38 Post R -Development 1- 1 0.783 12.050 11.58 38 Post R -Development 2- 2 1.132 12.030 17.02 38 Post -Development 10 10 2.292 12.020 34.92 38 Post -Development 25 25 3.138 12.020 47.69 005_ph2swtn_POST_100YRrouted_20171110.pp Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i c Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 1 of 6 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/s) (years) (ac-ft) 38 Post -Development 100 4.741 12.020 71.27 100-YR 3A Post R -Development 1- 1 3.020 12.030 46.74 3A Post R -Development 2- 2 4.126 12.010 64.01 3A Post -Development 10 10 7.620 12.010 117.01 3A Post -Development 25 25 10.076 12.010 153.16 3A Post -Development 100 14.631 12.010 218.46 100-YR 2 Post R -Development 1- 1 3.398 12.020 53.35 2 Post R -Development 2- 2 4.731 12.020 74.64 2 Post -Development 10 10 9.017 12.020 141.02 2 Post -Development 25 25 12.067 12.010 186.81 2 Post -Development 100 17.763 12.000 270.76 100-YR 1 Post R -Development 1- 1 1.514 12.050 21.82 1 Post R -Development 2- 2 2.205 12.050 32.49 1 Post -Development 10 10 4.519 12.030 67.54 1 Post -Development 25 25 6.215 12.030 92.73 1 Post -Development 100 9.439 12.020 139.58 100-YR 5B Post R -Development 1- 1 0.796 12.060 11.25 5B Post R -Development 2- 2 1.109 12.060 15.78 5B Post -Development 10 10 2.113 12.060 29.93 5B Post -Development 25 25 2.828 12.060 39.70 5B Post -Development 100 4.163 12.050 57.52 100-YR 6 Post R -Development 1- 1 0.647 12.020 10.08 6 Post R -Development 2- 2 0.927 12.020 14.64 6 Post -Development 10 10 1.849 12.010 29.27 005_ph2swtn_POST_100YRrouted_20171110.pp Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Val c Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 2 of 6 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/s) (years) (ac-ft) 6 Post -Development 25 25 2.517 12.010 39.62 6 Post -Development 100 3.780 12.000 58.72 100-YR 7 Post R -Development 1- 1 0.724 12.070 9.54 7 Post R -Development 2- 2 1.041 12.060 14.08 7 Post -Development 10 10 2.093 12.060 28.80 7 Post -Development 25 25 2.858 12.060 39.24 7 Post -Development 100 4.304 12.060 58.52 100-YR Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/s) (years) (ac-ft) OUT Post R -Development 1- 1 16.245 12.040 119.97 DUf Post R -Development 2- 2 23.087 12.090 198.86 DUf Post -Development 10 10 45.368 12.060 550.13 DUf Post -Development 25 25 61.305 12.060 780.33 DUf Post -Development 100 91.455 12.050 1,198.05 100-YR J-4A Post R -Development 1- 1 2.516 12.040 38.27 J-4A Post R -Development 2- 2 3.646 12.020 56.41 J-4A Post -Development 10 10 7.416 12.010 116.25 J-4A Post -Development 25 25 10.170 12.010 158.95 J-4A Post -Development 100 15.393 12.010 237.91 100-YR J 38 Post R -Development 1- 1 0.783 12.050 11.58 J-38 Post R -Development 2- 2 1.132 12.030 17.02 J-38 Post -Development 10 10 2.292 12.020 34.92 J-38 Post -Development 25 25 3.138 12.020 47.69 005_ph2swtn_POST_100YRrouted_20171110.pp Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Val c Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 3 of 6 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/S) (years) (ac-ft) J 38 Post -Development 100 4.741 12.020 71.27 100-YR 5 Post R -Development 1- 1 1.269 12.030 18.52 5 Post R -Development 2- 2 1.776 12.020 26.15 5 Post -Development 10 10 3.415 12.020 50.16 5 Post -Development 25 25 4.586 12.020 66.80 J-5 Post -Development 100 6.777 12.020 97.12 100-YR 6 Post R -Development 1- 1 0.647 12.020 10.08 6 Post R -Development 2- 2 0.927 12.020 14.64 6 Post -Development 10 10 1.849 12.010 29.27 J-6 Post -Development 25 25 2.517 12.010 39.62 J-6 Post -Development 100 3.780 12.000 58.72 100-YR 1 Post R -Development 1- 1 1.514 12.050 21.82 1 Post R -Development 2- 2 2.205 12.050 32.49 1 Post -Development 10 10 4.519 12.030 67.54 J-1 Post -Development 25 25 6.215 12.030 92.73 J-1 Post -Development 100 9.439 12.020 139.58 100-YR J-2 Post R -Development 1- 1 3.398 12.020 53.35 J-2 Post R -Development 2- 2 4.731 12.020 74.64 J-2 Post -Development 10 10 9.017 12.020 141.02 J-2 Post -Development 25 25 12.067 12.010 186.81 J-2 Post -Development 100 17.763 12.000 270.76 100-YR 3-A Post R -Development 1- 1 8.693 12.360 42.57 3-A Post R -Development 2- 2 12.407 12.230 94.83 3-A Post -Development 10 10 24.475 12.140 280.55 005_ph2swrn_POST_100YRrouted_20171110.pp Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i c Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 4 of 6 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/S) (years) (ac-ft) J-A Post -Development 25 25 33.062 12.110 405.90 A Post -Development 100 49.394 12.100 628.65 100-YR J 48 Post R -Development 1- 1 3.517 12.040 51.62 JAB Post R -Development 2- 2 5.053 12.040 75.39 J 46 Post -Development 10 10 10.137 12.020 152.46 3-413 Post -Development 25 25 13.832 12.020 207.36 3-46 Post -Development 100 20.819 12.010 308.60 100-YR J-3A Post R -Development 1- 1 3.803 12.030 58.26 J 3A Post R -Development 2- 2 5.258 12.020 80.85 J-3A Post -Development 10 10 9.912 12.010 151.56 J 3A Post -Development 25 25 13.214 12.010 200.43 J-3A Post -Development 100 19.372 12.010 289.27 100-YR J 5A Post R -Development 1- 1 0.472 11.990 7.90 J 5A Post R -Development 2- 2 0.667 11.980 11.26 J_5A Post -Development 10 10 1.302 11.970 22.01 3_5A Post -Development 25 25 1.758 11.970 29.51 J-5A Post -Development 100 2.614 11.970 43.24 100-YR Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (fta/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) post- Il (IN) Development 1 9.853 12.040 135.02 (N/A)F7.(N/ A)BMP 1-YR BMP Il post- (DUF) Development 1 8.693 12.360 42.57 342.52927 1-YR 005_ph2swrn_POST_100YRrouted_20171110.pp Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i c Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 5 of 6 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (fit) Poi BMP Il (IN) Development 2 13.756 12.040 190.86 (N/A) (N/A) 2-YR BMP Il Post (DUFF) Development 2 12.407 12.230 94.83 342.98 8.796 2-YR Poi BMP Il (IN) Development 10 26.369 12.040 366.76 (N/A) (N/A) 10-YR BMP Il Post (DUFF) Development 10 24.475 12.140 280.55 344.07 10.915 10-YR Poi BMP Il (IN) Development 25 35.383 12.030 489.66 (N/A) (N/A) 25-YR BMP Il Post (DUFF) Development 25 33.062 12.110 405.90 344.60 12.015 25-YR Poi BMP Il (IN) Development 100 52.262 12.030 714.31 (N/A) (N/A) 100-YR BMP I1 Poi (DUFF) Development Development 100 49.394 12.100 628.65 345.30 13.586 005_ph2swm_POST_100YRrouted_20171110.pp Bentley Systems, Inc. Haestad Methods Solution Bentley PondPecl( V8i C Center [08.11.01.561 1/22/2018 27 Siemon Company Drive Suite 200 W Page 6 of 6 Watertown, CT 06795 USA +1-203-755-1666 Appendix A — Pond Pack Master Network Summary (BMP Post -Development Routing) Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (ft3/s) (years) (ac-ft) DA-G1 Post -Development 1- 1 0.304 11.920 5.73 DA-G1 Post R -Development 2- 2 0.400 11.920 7.47 DA-G1 Post R -Development 5- 5 0.555 11.920 10.24 DA-G1 Ps -Development 10 10 0.691 11.920 12.60 DA-G1 Post -Development 25 25 0.891 11.920 16.03 DA-G1 Post -Development 50 50 1.065 11.920 18.96 DA-G1 Post -Development 100 1.257 11.920 22.16 100-YR DA-G2 Post R -Development 1- 1 0.052 11.920 0.98 DA-G2 Post R -Development 2- 2 0.070 11.920 1.32 DA-G2 Post R -Development 5- 5 0.100 11.920 1.88 DA-G2 Post -Development 10 10 0.127 11.920 2.36 DA-G2 Post -Development 25 25 0.166 11.920 3.06 DA-G2 Post -Development 50 50 0.201 11.920 3.67 DA-G2 Post -Development 100 0.240 11.920 4.33 100-YR DA-G3 Post R -Development 1- 1 0.133 11.920 2.51 DA-G3 Post R -Development 2- 2 0.177 11.920 3.33 DA-G3 Post R -Development 5- 5 0.250 11.920 4.65 DA-G3 Post -Development 10 10 0.313 11.920 5.78 DA-G3 Post -Development 25 25 0.407 11.920 7.42 DA-G3 Post -Development 50 50 0.490 11.920 8.83 DA-G3 Post -Development 100 0.581 11.920 10.37 100-YR DA4243 Post R -Development 1- 1 0.487 12.010 7.97 DA-I2-I3 Post -Development 2- 2 0.673 11.990 11.04 YR DA4243 Post R -Development 5- 5 0.987 11.990 16.15 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Vitt 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 1 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/s) (years) (ac-ft) DA4243 Post -Development 10 10 1.267 11.990 20.60 DA4243 Post -Development 25 25 1.687 11.990 27.16 DA4243 Post -Development 50 50 2.058 11.990 32.84 DA4243 Post -Development 100 2.470 11.980 39.07 100-YR DA-I4a Post R -Development 1- 1 0.090 11.930 1.70 DA-I4a Post R -Development 2- 2 0.126 11.920 2.38 DA-I4a Post R -Development 5- 5 0.186 11.920 3.52 DA-I4a Post -Development 10 10 0.240 11.920 4.52 DA-I4a Post -Development 25 25 0.321 11.920 6.00 DA-I4a Post -Development 50 50 0.393 11.920 7.29 DA-I4a Post -Development 100 0.473 11.920 8.70 100-YR DA-31a Post R -Development 1- 1 0.194 12.040 2.78 DA-31a Post R -Development 2- 2 0.293 12.040 4.37 DA-31a Post R -Development 5- 5 0.470 12.040 7.18 DA-31a Post -Development 10 10 0.635 12.020 9.75 DA-31a Post -Development 25 25 0.891 12.020 13.73 DA-31a Post -Development 50 50 1.123 12.020 17.28 DA-31a Post -Development 100 1.385 12.010 21.24 100-YR DA-32a Post R -Development 1- 1 0.152 12.000 2.51 DA-32a Post R -Development 2- 2 0.220 11.980 3.71 DA-32a Post R -Development 5- 5 0.340 11.970 5.79 DA-32a Post -Development 10 10 0.449 11.970 7.66 DA-32a Post -Development 25 25 0.616 11.960 10.48 DA-32a Post -Development 50 50 0.766 11.960 12.97 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack vat 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 2 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/s) (years) (ac-ft) DA-32a Post -Development 100 0.934 11.960 15.73 100-YR DA-31b Post R -Development 1- 1 0.373 11.920 7.05 DA-31b Post R -Development 2- 2 0.500 11.920 9.43 DA-31b Post R -Development 5- 5 0.711 11.920 13.30 DA-31b Post -Development 10 10 0.895 11.920 16.61 DA-31b Post -Development 25 25 1.170 11.920 21.44 DA-31b Post -Development 50 50 1.411 11.920 25.59 DA-31b Post -Development 100 1.677 11.920 30.11 100-YR DA-32b Post R -Development 1- 1 0.358 11.920 6.77 DA-32b Post R -Development 2- 2 0.477 11.920 8.97 DA-32b Post R -Development 5- 5 0.673 11.920 12.53 DA-32b Post -Development 10 10 0.844 11.920 15.57 DA-32b Post -Development 25 25 1.098 11.920 20.00 DA-32b Post -Development 50 50 1.320 11.920 23.80 DA-32b Post -Development 100 1.565 11.920 27.94 100-YR DA-35 Post R -Development 1- 1 0.210 11.920 3.96 DA-35 Post R -Development 2- 2 0.276 11.920 5.16 DA-15 Post R -Development 5- 5 0.384 11.920 7.08 DA-15 Post -Development 10 10 0.478 11.920 8.72 DA-15 Post -Development 25 25 0.616 11.920 11.08 DA-35 Post -Development 50 50 0.736 11.920 13.11 DA-35 Post -Development 100 0.869 11.920 15.32 100-YR DA-33 Post R -Development 1- 1 0.108 11.920 2.04 DA-33 Post R -Development 2- 2 0.144 11.920 2.70 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack vat 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 3 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/s) (years) (ac-ft) DA-33 Post R -Development 5- 5 0.203 11.920 3.77 DA-33 Post -Development 10 10 0.254 11.920 4.69 DA-33 Post -Development 25 25 0.331 11.920 6.02 DA-33 Post -Development 50 50 0.397 11.920 7.17 DA-33 Post -Development 100 0.471 11.920 8.41 100-YR DA-H1 Post R -Development 1- 1 0.169 11.920 3.20 DA-H1 Post R -Development 2- 2 0.227 11.920 4.28 DA-H1 Post R -Development 5- 5 0.323 11.920 6.04 DA-H1 Ps -Development 10 10 0.406 11.920 7.54 DA-H 1 Post -Development 25 25 0.531 11.920 9.73 DA-H 1 Post -Development 50 50 0.641 11.920 11.62 DA-H1 Post -Development 100 0.761 11.920 13.67 100-YR DA-Il Post R -Development 1- 1 9.628 12.080 126.68 DA-Il Post R -Development 2- 2 13.514 12.080 180.05 DA-Il Post R -Development 5- 5 20.153 12.080 269.68 DA-Il Post -Development 10 10 26.102 12.070 348.84 DA-Il Post -Development 25 25 35.108 12.070 466.72 DA-Il Post -Development 50 50 43.094 12.070 569.43 DA-Il Post -Development 100 51.980 12.070 682.09 100-YR DA-II-PRE Post R -Development 1- 1 7.779 12.080 99.08 DA-II-PRE Post R -Development 2- 2 11.297 12.080 148.10 DA-II-PRE Post R -Development 5- 5 17.446 12.080 232.59 DA-II-PRE Post -Development 10 10 23.053 12.080 308.45 R DA-Il-PRE Post -Development 25 25 31.652 12.070 423.16 Bentley Systems, Inc. Haestad Methods Solution Bentley PonAPack Val 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 4 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/s) (years) (ac-ft) DA-IS-PRE Post -Development 50 50 39.353 12.070 524.46 DA-Il-PRE Post -Development 100 47.981 12.070 636.36 100-YR J6 Post R -Development 1- 1 0.045 11.930 0.84 J6 Post R -Development 2- 2 0.062 11.920 1.18 J6 Post R -Development 5- 5 0.092 11.920 1.74 J6 Post -Development 10 10 0.119 11.920 2.24 J6 Post -Development 25 25 0.159 11.920 2.97 J6 Post -Development 50 50 0.194 11.920 3.60 J6 Post -Development 100 0.234 11.920 4.30 100-YR J7 Post R -Development 1- 1 0.072 11.930 1.36 J7 Post R -Development 2- 2 0.100 11.920 1.88 J7 Post R -Development 5- 5 0.146 11.920 2.76 J7 Post -Development 10 10 0.188 11.920 3.52 J7 Post -Development 25 25 0.250 11.920 4.65 J7 Post -Development 50 50 0.305 11.920 5.63 J7 Post -Development 100 0.366 11.920 6.69 100-YR Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/s) (years) (ac-ft) 0-133 Post R -Development 1- 1 0.091 12.380 0.29 0-133 Post R -Development 2- 2 0.134 12.060 1.75 0-133 Post R -Development 5- 5 0.205 12.000 3.76 0-G3 Post -Development 10 10 0.267 11.960 5.14 0-133 Post -Development 25 25 0.359 11.950 6.83 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack vat 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 5 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/S) (years) (ac-ft) 0-G3 Post -Development 50 50 0.440 11.950 8.21 0-G3 Post -Development 100 0.529 11.950 9.68 100-YR 0-132 Post R -Development 1- 1 0.032 12.060 0.50 0-132 Post R -Development 2- 2 0.050 12.020 1.04 0-132 Post R -Development 5- 5 0.080 11.960 1.74 0-G2 Post -Development 10 10 0.107 11.950 2.22 0-G2 Post -Development 25 25 0.147 11.940 2.91 0-G2 Post -Development 50 50 0.181 11.940 3.51 0-G2 Post -Development 100 0.220 11.940 4.15 100-YR 0-G1 Post R -Development 1- 1 0.234 12.040 3.55 0-GI Post R -Development 2- 2 0.326 12.010 5.92 0-GI Post R -Development 5- 5 0.476 11.970 9.02 0-GI Post -Development 10 10 0.606 11.960 11.34 0-GI Post -Development 25 25 0.798 11.960 14.58 0-GI Post -Development 50 50 0.966 11.950 17.37 0-GI Post -Development 100 1.156 11.950 20.39 100-YR 042-I3 Post R -Development 1- 1 0.362 12.150 3.74 042-I3 Post R -Development 2- 2 0.537 12.090 8.09 042-I3 Post R -Development 5- 5 0.843 12.050 14.62 042-I3 Post -Development 10 10 1.121 12.030 19.48 042-I3 Post -Development 25 25 1.540 12.030 25.97 042-I3 Post -Development 50 50 1.910 12.030 30.88 042-I3 Post -Development 100 2.321 12.040 36.23 100-YR 044 Post R -Development 1- 1 0.053 12.150 0.33 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Vitt 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 6 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/S) (years) (ac-ft) O44 Post R -Development 2- 2 0.089 12.050 1.53 O44 Post R -Development 5- 5 0.149 12.000 2.98 O44 Post -Development 10 10 0.203 11.970 4.05 O44 Post -Development 25 25 0.284 11.960 5.49 O44 Post -Development 50 50 0.356 11.950 6.70 O44 Post -Development 100 0.435 11.950 8.05 100-YR 0-31 Post R -Development 1- 1 0.562 12.060 6.12 0-31 Post R -Development 2- 2 0.786 12.050 9.34 0-31 Post R -Development 5- 5 1.171 12.050 15.10 0-31 Post -Development 10 10 1.519 12.040 20.31 0-31 Post -Development 25 25 2.047 12.030 28.12 0-31 Post -Development 50 50 2.517 12.030 35.04 0-31 Post -Development 100 3.043 12.030 42.65 100-YR 0 32 Post R -Development 1- 1 0.504 12.050 6.25 0 32 Post R -Development 2- 2 0.690 12.040 9.46 0 32 Post R -Development 5- 5 1.004 12.020 14.82 0 32 Post -Development 10 10 1.282 12.020 19.40 0 32 Post -Development 25 25 1.700 12.000 26.12 0 32 Post -Development 50 50 2.070 11.990 32.01 0-32 Post -Development 100 2.480 11.980 38.49 100-YR 0-35 Post R -Development 1- 1 0.172 12.010 3.17 0-35 Post R -Development 2- 2 0.236 11.960 4.68 0-35 Post R -Development 5- 5 0.342 11.950 6.67 0-35 Post -Development 10 10 0.435 11.940 8.26 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Vitt 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 7 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/S) (years) (ac-ft) 0-35 Post -Development 25 25 0.571 11.940 10.63 0-35 Post -Development 50 50 0.688 11.940 12.73 0-35 Post -Development 100 0.818 11.930 14.96 100-YR 0-33 Post R -Development 1- 1 0.075 12.490 0.19 0-33 Post R -Development 2- 2 0.110 12.060 1.41 0-33 Post R -Development 5- 5 0.168 12.000 3.08 0-33 Post -Development 10 10 0.218 11.960 4.22 0-33 Post -Development 25 25 0.293 11.950 5.60 0-33 Post -Development 50 50 0.359 11.950 6.71 0-33 Post -Development 100 0.432 11.950 7.91 100-YR 0-H1 Post R -Development 1- 1 0.133 12.050 1.91 0-H1 Post R -Development 2- 2 0.189 12.010 3.48 0-H1 Post R -Development 5- 5 0.283 11.960 5.53 0-H1 Ps -Development 10 10 0.365 11.950 7.02 0-H1 Post -Development 25 25 0.488 11.950 9.15 0-H1 Post -Development 50 50 0.595 11.950 10.97 0-H1 Post -Development 100 0.713 11.940 12.95 100-YR NODE -A Post R -Development 1- 1 8.468 12.450 36.32 NODE -A Post R -Development 2- 2 12.164 12.310 82.74 NODE -A Post R -Development 5- 5 18.507 12.220 179.17 NODE -A Post -Development 10 10 24.203 12.170 279.93 NODE -A Post -Development 25 25 32.778 12.160 398.53 NODE -A Post -Development 50 50 40.433 12.150 499.59 NODE -A Post -Development 100 49.105 12.140 609.43 100-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Vitt 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 8 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (ft3/S) (years) (ac-ft) NODE -A -PRE Post R -Development 1- 1 7.779 12.080 99.08 NODE -A -PRE Post R -Development 2- 2 11.297 12.080 148.10 NODE -A -PRE Post R -Development 5- 5 17.446 12.080 232.59 NODE -A -PRE Post -Development 10 10 23.053 12.080 308.45 NODE -A -PRE Post -Development 25 25 31.652 12.070 423.16 NODE -A -PRE Post -Development 50 50 39.353 12.070 524.46 NODE -A -PRE Post -Development 100 47.981 12.070 636.36 100-YR 0-36 Post R -Development 1- 1 0.045 11.930 0.84 0-36 Post R -Development 2- 2 0.062 11.920 1.18 0-36 Post R -Development 5- 5 0.092 11.920 1.74 0-36 Post -Development 10 10 0.119 11.920 2.24 0-36 Post -Development 25 25 0.159 11.920 2.97 0-36 Post -Development 50 50 0.194 11.920 3.60 0-36 Post -Development 100 0.234 11.920 4.30 100-YR 0-37 Post R -Development 1- 1 0.072 11.930 1.36 0 37 Post R -Development 2- 2 0.100 11.920 1.88 0 37 Post R -Development 5- 5 0.146 11.920 2.76 0 37 Post -Development 10 10 0.188 11.920 3.52 0 37 Post -Development 25 25 0.250 11.920 4.65 0-37 Post -Development 50 50 0.305 11.920 5.63 0-37 Post -Development 100 0.366 11.920 6.69 100-YR Pond Summary Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack Vitt 005_1h2swrn_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 9 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (fta/S) (years) (ac-ft) Maximum Maximum Water Pond Storage Surface (ac-ft) Elevation (ft) Post- BMP-G3 (IN) Development 1 0.133 11.920 2.51 (N/A) (N/A) 1-YR BMP G3 Post (DUFF) Development 1 0.091 12.380 0.29 359.01 0.070 1-YR Post- BMP-G3 (IN) Development 2 0.177 11.920 3.33 (N/A) (N/A) 2-YR BMP G3 Post (DUFF) Development 2 0.134 12.060 1.75 359.14 0.080 2-YR Post- BMP-G3 (IN) Development 5 0.250 11.920 4.65 (N/A) (N/A) 5-YR BMP G3 Post (DUFF) Development 5 0.205 12.000 3.76 359.25 0.088 5-YR Poi BMP-G3 (IN) Development 10 0.313 11.920 5.78 (N/A) (N/A) 10-YR BMP G3 Post (DUFF) Development 10 0.267 11.960 5.14 359.31 0.094 10-YR Poi BMP-G3 (IN) Development 25 0.407 11.920 7.42 (N/A) (N/A) 25-YR BMP G3 Post (DUFF) Development 25 0.359 11.950 6.83 359.38 0.099 25-YR Poi BMP-G3 (IN) Development 50 0.490 11.920 8.83 (N/A) (N/A) 50-YR BMP G3 Post (DUFF) Development 50 0.440 11.950 8.21 359.43 0.103 50-YR Poi BMP-G3 (IN) Development 100 0.581 11.920 10.37 (N/A) (N/A) 100-YR BMP G3 Post (DUFF) Development 100 0.529 11.950 9.68 359.48 0.108 100-YR Poi BMP-G2 (IN) Development 1 0.052 11.920 0.98 (N/A) (N/A) 1-YR Bentley Systems, Inc. Haestad Methods Solution 005_1h2sven_bmps_20170829.ppc Center 4/16/2018 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Bentley Pondl vat [08.11.01.561 Page 10 of 20 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) BMP-G2 Post (DUFF) Development 1 0.032 12.060 0.50 356.56 0.022 1-YR Poi BMP-G2 (IN) Development 2 0.070 11.920 1.32 (N/A) (N/A) 2-YR BMP-G2 Post (DUFF) Development 2 0.050 12.020 1.04 356.61 0.024 2-YR Poi BMP-G2 (IN) Development 5 0.100 11.920 1.88 (N/A) (N/A) 5-YR BMP-G2 Post (DUFF) Development 5 0.080 11.960 1.74 356.65 0.026 5-YR Poi BMP-G2 (IN) Development 10 0.127 11.920 2.36 (N/A) (N/A) 10-YR BMP-G2 Post (DUFF) Development 10 0.107 11.950 2.22 356.68 0.028 10-YR Poi BMP-G2 (IN) Development 25 0.166 11.920 3.06 (N/A) (N/A) 25-YR BMP-G2 Post (DUFF) Development 25 0.147 11.940 2.91 356.72 0.029 25-YR Poi BMP-G2 (IN) Development 50 0.201 11.920 3.67 (N/A) (N/A) 50-YR BMP-G2 Post (DUFF) Development 50 0.181 11.940 3.51 356.75 0.031 50-YR Poi BMP-G2 (IN) Development 100 0.240 11.920 4.33 (N/A) (N/A) 100-YR BMP-G2 Post (DUFF) Development 100 0.220 11.940 4.15 356.78 0.032 100-YR Poi BMP-Gl (IN) Development 1 0.304 11.920 5.73 (N/A) (N/A) 1-YR 1 BMPF) Poi (DM Development 1 0.234 12.040 3.55 353.24 0.127 1-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok V8i 005_1h2sven_bmps_201701 Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 11 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (fit) Poi BMP-Gl (IN) Development 2 0.400 11.920 7.47 (N/A) (N/A) 2-YR BMP-G1 Post (OUF) Development 2 0.326 12.010 5.92 353.34 0.139 2-YR Poi BMP-GI (IN) Development 5 0.555 11.920 10.24 (N/A) (N/A) 5-YR BMP-G1 Post (OUF) Development 5 0.476 11.970 9.02 353.46 0.153 5-YR Poi BMP-GI (IN) Development 10 0.691 11.920 12.60 (N/A) (N/A) 10-YR BMP-G1 Post (OUF) Development 10 0.606 11.960 11.34 353.53 0.162 10-YR Poi BMP-Gl (IN) Development 25 0.891 11.920 16.03 (N/A) (N/A) 25-YR BMP-G1 Post (OUF) Development 25 0.798 11.960 14.58 353.63 0.174 25-YR Poi BMP-GI (IN) Development 50 1.065 11.920 18.96 (N/A) (N/A) 50-YR BMP-G1 Post (OUF) Development 50 0.966 11.950 17.37 353.71 0.184 50-YR Poi BMP-GI (IN) Development 100 1.257 11.920 22.16 (N/A) (N/A) 100-YR BMP-G1 Post (OUF) Development 100 1.156 11.950 20.39 353.80 0.194 100-YR BMP-I2-I3 Post (IN) Development 1 0.487 12.010 7.97 (N/A) (N/A) 1-YR BMP-I2-I3 Post (OUF) Development 1 0.362 12.150 3.74 353.05 0.185 1-YR BMP-I2-I3 Poi (IN) Development 2 0.673 11.990 11.04 (N/A) (N/A) 2-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok vat 005_1h2sven_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 12 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) BMP-I2-I3 Post (OUF) Development 2 0.537 12.090 8.09 353.22 0.216 2-YR BMP-I2-I3 Post (IN) Development 5 0.987 11.990 16.15 (N/A) (N/A) 5-YR BMP-I2-I3 Post (OM Development 5 0.843 12.050 14.62 353.40 0.248 5-YR BMP-I2-I3 Post (IN) Development 10 1.267 11.990 20.60 (N/A) (N/A) 10-YR BMP-I2-I3 Post (OM Development 10 1.121 12.030 19.48 353.50 0.264 10-YR BMP-I2-I3 Post (IN) Development 25 1.687 11.990 27.16 (N/A) (N/A) 25-YR BMP-I2-I3 Post (OM Development 25 1.540 12.030 25.97 353.61 0.285 25-YR BMP-I2-I3 Post (IN) Development 50 2.058 11.990 32.84 (N/A) (N/A) 50-YR BMP-I2-I3 Post (OM Development 50 1.910 12.030 30.88 353.73 0.308 50-YR BMP-I2-I3 Post (IN) Development 100 2.470 11.980 39.07 (N/A) (N/A) 100-YR BMP-I2-I3 Post (OM Development 100 2.321 12.040 36.23 353.89 0.337 100-YR Poi BMP-I4 (IN) Development 1 0.090 11.930 1.70 (N/A) (N/A) 1-YR BMP-I4 Post (OM Development 1 0.053 12.150 0.33 355.07 0.040 1-YR Poi BMP-I4 (IN) Development 2 0.126 11.920 2.38 (N/A) (N/A) 2-YR BMP-I4 Poi (D� Development 2 0.089 12.050 1.53 355.22 0.047 2-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok vat 005_1h2sven_bmps_201701 Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 13 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) Poi BMP-I4 (IN) Development 5 0.186 11.920 3.52 (N/A) (N/A) 5-YR BMP-I4 Post (OUF) Development 5 0.149 12.000 2.98 355.34 0.053 5-YR Poi BMP-I4 (IN) Development 10 0.240 11.920 4.52 (N/A) (N/A) 10-YR BMP-I4 Post (Dui Development 10 0.203 11.970 4.05 355.42 0.057 10-YR Poi BMP-I4 (IN) Development 25 0.321 11.920 6.00 (N/A) (N/A) 25-YR BMP-I4 Post (OM Development 25 0.284 11.960 5.49 355.51 0.062 25-YR Poi BMP-I4 (IN) Development 50 0.393 11.920 7.29 (N/A) (N/A) 50-YR BMP-I4 Post (OM Development 50 0.356 11.950 6.70 355.58 0.066 50-YR Poi BMP-I4 (IN) Development 100 0.473 11.920 8.70 (N/A) (N/A) 100-YR BMP-I4 Post (OM Development 100 0.435 11.950 8.05 355.66 0.071 100-YR Poi BMP-31 (IN) Development 1 0.567 11.940 8.81 (N/A) (N/A) 1-YR BMP-31 Post (OM Development 1 0.562 12.060 6.12 333.98 0.224 1-YR Poi BMP-31 (IN) Development 2 0.793 11.940 12.43 (N/A) (N/A) 2-YR BMP-31 Post (OM Development 2 0.786 12.050 9.34 334.11 0.260 2-YR Poi BMP-31 (IN) Development 5 1.181 11.940 18.54 (N/A) (N/A) 5-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPe4ok vat 005_1h2sven_bmps_201701 Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 14 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (fit) BMP-31 Post (OUF) Development 5 1.171 12.050 15.10 334.28 0.312 5-YR Poi BMP-31 (IN) Development 10 1.530 11.940 23.94 (N/A) (N/A) 10-YR BMP-31 Post (OUF) Development 10 1.519 12.040 20.31 334.41 0.351 10-YR Poi BMP-31 (IN) Development 25 2.062 11.930 32.04 (N/A) (N/A) 25-YR BMP-31 Post (OUF) Development 25 2.047 12.030 28.12 334.58 0.403 25-YR Poi BMP-31 (IN) Development 50 2.535 11.930 39.14 (N/A) (N/A) 50-YR BMP-31 Post (OUF) Development 50 2.517 12.030 35.04 334.72 0.445 50-YR Poi BMP-31 (IN) Development 100 3.062 11.930 46.97 (N/A) (N/A) 100-YR BMP-31 Post (OUF) Development 100 3.043 12.030 42.65 334.85 0.486 100-YR Poi BMP-32 (IN) Development 1 0.510 11.930 8.97 (N/A) (N/A) 1-YR BMP-J2 Post (OUF) Development 1 0.504 12.050 6.25 330.99 0.262 1-YR Poi BMP-32 (IN) Development 2 0.697 11.930 12.32 (N/A) (N/A) 2-YR BMP-J2 Post (OUF) Development 2 0.690 12.040 9.46 331.11 0.290 2-YR Poi BMP-32 (IN) Development 5 1.012 11.930 17.85 (N/A) (N/A) 5-YR BMP-J2 elopment (off De 5 1.004 12.020 14.82 331.25 0.326 5-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok V8i 005_1h2sven_bmps_201701 Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 15 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) Poi BMP-32 (IN) Development 10 1.293 11.930 22.67 (N/A) (N/A) 10-YR BMP-J2 Post (DUFF) Development 10 1.282 12.020 19.40 331.35 0.352 10-YR Poi BMP-32 (IN) Development 25 1.714 11.930 29.79 (N/A) (N/A) 25-YR BMP-J2 Post (DUFF) Development 25 1.700 12.000 26.12 331.49 0.387 25-YR Poi BMP-32 (IN) Development 50 2.086 11.930 35.98 (N/A) (N/A) 50-YR BMP-J2 Post (DUFF) Development 50 2.070 11.990 32.01 331.59 0.414 50-YR Poi BMP-32 (IN) Development 100 2.499 11.930 42.75 (N/A) (N/A) 100-YR BMP-J2 Post (DUFF) Development 100 2.480 11.980 38.49 331.69 0.442 100-YR Poi BMP-35 (IN) Development 1 0.210 11.920 3.96 (N/A) (N/A) 1-YR BMP-35 Post (DUFF) Development 1 0.172 12.010 3.17 352.22 0.074 1-YR Poi BMP-35 (IN) Development 2 0.276 11.920 5.16 (N/A) (N/A) 2-YR BMP-35 Post (DUFF) Development 2 0.236 11.960 4.68 352.29 0.078 2-YR Poi BMP-35 (IN) Development 5 0.384 11.920 7.08 (N/A) (N/A) 5-YR BMP-35 Post (DUFF) Development 5 0.342 11.950 6.67 352.37 0.084 5-YR Poi BMP-35 (IN) Development 10 0.478 11.920 8.72 (N/A) (N/A) 10-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok vat 005_1h2sven_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 16 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) BMP-35 Post (DUFF) Development 10 0.435 11.940 8.26 352.43 0.088 10-YR Poi BMP-35 (IN) Development 25 0.616 11.920 11.08 (N/A) (N/A) 25-YR BMP-35 Post (DUFF) Development 25 0.571 11.940 10.63 352.51 0.093 25-YR Poi BMP-35 (IN) Development 50 0.736 11.920 13.11 (N/A) (N/A) 50-YR BMP-35 Post (DUFF) Development 50 0.688 11.940 12.73 352.56 0.097 50-YR Poi BMP-35 (IN) Development 100 0.869 11.920 15.32 (N/A) (N/A) 100-YR BMP-35 Post (DUFF) Development 100 0.818 11.930 14.96 352.61 0.100 100-YR Poi BMP-33 (IN) Development 1 0.108 11.920 2.04 (N/A) (N/A) 1-YR BMP-J3 Post (DUFF) Development 1 0.075 12.490 0.19 352.99 0.056 1-YR Poi BMP-33 (IN) Development 2 0.144 11.920 2.70 (N/A) (N/A) 2-YR BMP-J3 Post (DUFF) Development 2 0.110 12.060 1.41 353.12 0.065 2-YR Poi BMP-33 (IN) Development 5 0.203 11.920 3.77 (N/A) (N/A) 5-YR BMP-J3 Post (DUFF) Development 5 0.168 12.000 3.08 353.21 0.071 5-YR Poi BMP-33 (IN) Development 10 0.254 11.920 4.69 (N/A) (N/A) 10-YR BMP-J3 Poi (DUFF) Development 10 0.218 11.960 4.22 353.27 0.075 10-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok V8i 005_1h2sven_bmps_201701 Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 17 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (fit) Poi BMP-33 (IN) Development 25 0.331 11.920 6.02 (N/A) (N/A) 25-YR BMP-J3 Post (OM Development 25 0.293 11.950 5.60 353.33 0.079 25-YR Poi BMP-33 (IN) Development 50 0.397 11.920 7.17 (N/A) (N/A) 50-YR BMP-J3 Post (OM Development 50 0.359 11.950 6.71 353.37 0.083 50-YR Poi BMP-33 (IN) Development 100 0.471 11.920 8.41 (N/A) (N/A) 100-YR BMP-J3 Post (OM Development 100 0.432 11.950 7.91 353.42 0.086 100-YR Poi BMP-Hl (IN) Development 1 0.169 11.920 3.20 (N/A) (N/A) 1-YR BMP-Hl Post (OM Development 1 0.133 12.050 1.91 357.15 0.069 1-YR Poi BMP-Hl (IN) Development 2 0.227 11.920 4.28 (N/A) (N/A) 2-YR BMP-Hl Post (OM Development 2 0.189 12.010 3.48 357.23 0.075 2-YR Poi BMP-Hl (IN) Development 5 0.323 11.920 6.04 (N/A) (N/A) 5-YR BMP-Hl Post (OM Development 5 0.283 11.960 5.53 357.32 0.082 5-YR Poi BMP-Hl (IN) Development 10 0.406 11.920 7.54 (N/A) (N/A) 10-YR BMP-Hl Post (OM Development 10 0.365 11.950 7.02 357.38 0.086 10-YR Poi BMP-Hl (IN) Development 25 0.531 11.920 9.73 (N/A) (N/A) 25-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok vat 005_1h2sven_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 18 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (fit) BMP-Hl Post (OM Development 25 0.488 11.950 9.15 357.46 0.092 25-YR Poi BMP-Hl (IN) Development 50 0.641 11.920 11.62 (N/A) (N/A) 50-YR BMP-Hl Post (OM Development 50 0.595 11.950 10.97 357.52 0.097 50-YR Poi BMP-Hl (IN) Development 100 0.761 11.920 13.67 (N/A) (N/A) 100-YR BMP-Hl Post (OM Development 100 0.713 11.940 12.95 357.58 0.102 100-YR Poi BMP-Il (IN) Development 1 9.628 12.080 126.68 (N/A) (N/A) 1-YR BMP-Il Post (Our) OM Development 1 8.468 12.450 36.32 342.52 7.938 1-YR Poi BMP-Il (IN) Development 2 13.514 12.080 180.05 (N/A) (N/A) 2-YR BMP-Il Post (OM Development 2 12.164 12.310 82.74 343.04 8.898 2-YR Poi BMP-Il (IN) Development 5 20.153 12.080 269.68 (N/A) (N/A) 5-YR BMP-Il Post (OM Development 5 18.507 12.220 179.17 343.74 10.249 5-YR Poi BMP-Il (IN) Development 10 26.102 12.070 348.84 (N/A) (N/A) 10-YR BMP-Il Post (OM Development 10 24.203 12.170 279.93 344.11 10.992 10-YR Poi BMP-Il (IN) Development 25 35.108 12.070 466.72 (N/A) (N/A) 25-YR BMP-Il Poi (OM Development Development 25 32.778 12.160 398.53 344.57 11.956 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok vat 005_1h2sven_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 19 of 20 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) Poi BMP-Il (IN) Development 50 43.094 12.070 569.43 (N/A) (N/A) 50-YR BMP-Il Post (DM Development 50 40.433 12.150 499.59 344.91 12.712 50-YR Poi BMP-Il (IN) Development 100 51.980 12.070 682.09 (N/A) (N/A) 100-YR BMP-IS Poi (D� Development 100 49.105 12.140 609.43 345.24 13.460 100-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPeCok vat 005_1h2sven_bmps_20170829.ppc Center [08.11.01.561 4/16/2018 27 Siemon Company Drive Suite 200 W Page 20 of 20 Watertown, CT 06795 USA +1-203-755-1666 Appendix B — BMP Stage Storage BMP G1- BIORETENTION L2 Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 352 4,000.92 0.092 0.00 0.00 0.00 0.000 354 5,616.88 0.129 14,358.34 9,572.22 9,572.22 0.220 356 7,459.04 0.171 19,548.67 13,032.45 22,604.67 0.519 BMP G2 - BIORETENTION (L2) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 357 1,588.70 0.036 0.00 0.00 0.00 0.000 358 2,918.50 0.067 6,660.48 2,220.16 2,220.16 0.051 BMP G3 - BIORETENTION (L2) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 358 2,675.47 0.061 0.00 0.00 0.00 0.000 360 4,155.21 0.095 10,164.92 6,776.61 6,776.61 0.156 362 5,861.36 0.135 14,951.67 9,967.78 16,744.39 0.384 BMP I2 - BIORETENTION (L2) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 35L8 3,574.70 0.082 0.00 0.00 0.00 0.000 352 3,728.20 0.086 10,953.54 730.24 730.24 0.017 353 4,557.50 0.105 12,407.75 4,135.92 4,866.15 0.112 BMPI3 - BIORETENTION (L2) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 353 1,882.12 0.043 0.00 0.00 0.00 0.000 354 2,440.38 0.056 6,465.65 2,155+22 2,155.22 0.049 356 3,434.29 0.079 8,769.66 5,846.44 8,001.66 0.184 358 4,410.00 0.101 11,735.98 7,823.98 15,825.64 0.363 BMP74 - WET SWALE (L2) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 354 1,269.48 0.029 0.00 0.00 0.00 0.000 355 1,981.47 0.045 4,836.96 1,612.32 1,612.32 0.037 356 2,824.63 0.065 7,171.88 2,390.63 4,002.95 0.092 BMP J1- WET SWALE (L2) REVISED 4112118 Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 333 2,167.93 0.050 2,610.84 2,610.84 2,610.84 0.060 333.5 7,521.56 0.173 13,727.59 2,287.93 4,898.77 0.112 334 12,547.52 0.288 29,783.86 4,963.98 9,862.75 0.226 336 16,164.78 0.371 42,954.07 28,636.04 38,498.79 0.884 BMP J2 - WET SWALE (L2) REVISED 4112118 Elevation (ft) Area (SF) Area AC Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume C Cumulative Volume AC-ft 326 25.71 0.001 0.00 0.00 0.00 0.000 329.5 1,250.96 0.029 1,456.01 1,698.68 1,698.68 0.039 330 4,705.31 0.108 8,382.41 1,397.07 3,095.74 0.071 330.5 9,225.56 0.212 20,519.43 3,419.90 6,515.65 0.150 332 12,755.88 0.293 32,829.49 16,414.74 22,930.39 0.526 BMP B - BIORETENTION LI Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 352 2,101.90 0.048 0.00 0.00 0.00 0.000 354 3,796.00 0.087 8,722.58 5,815.05 5,815.05 0.133 BMP JS - BIORETENTION (LI) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 351 2,378.30 0.055 0.00 0.00 0.00 0.000 352 2,797.00 0.064 7,754.47 2,584.82 2,584.82 0.059 353 3,226.50 0.074 9,027.58 3,009.19 5,594.02 0.128 BMP HI - BIORETENTION (L2) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 356 2,225.57 0.051 0.00 0.00 0.00 0.000 357 2,938.04 0.067 7,720.72 2,573.57 2,573.57 0.059 358 3,963.88 0.091 10,314.55 3,438.18 6,011.76 0.138 360 5,808.53 0.133 14,570.78 9,713.85 15,725.61 0.361 SWM BMP H (revised 1012512017) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 334 17,247.30 0.396 0.00 0.00 0.00 0.000 336 25,660.50 0.589 63,945.25 42,630.17 42,630.17 0.979 338 32,984.00 0.757 87,737.21 58,491.48 101,121.64 2.321 338.5 35,489.00 0.815 102,686.58 17,114.43 118,236.07 2.714 340 47,007.90 1.079 123,341.28 61,670.64 179,906.71 4.130 340.5 56,795.20 1.304 155,473.43 25,912.24 205,818.95 4.725 341 1 61,840.80 1.420 177,900.33 29,650.05 235,469.01 5.406 342 77,065.50 1.769 207,941.02 69,313.67 304,782.68 6.997 344 87,578.20 2.011 246,797.57 164,531.71 469,314.39 10.774 346 109,874.10 2.522 295,547.03 197,031.35 666,345.74 15.297 SWM BMP H (Forebay #1) Elevation (ft) Area (SF) Area AC Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume C Cumulative Volume AC-ft 336 3,179.30 0.073 0.00 0.00 0.00 0.000 338 3,992.44 0.092 10,734.49 7,156.32 7,156.32 0.164 340 5,454.30 0.125 14,113.21 9,408.81 16,565.13 0.380 341 7,296.40 0.168 19,059.17 6,353.06 22,918.19 0.526 SWM BMP H (Forebay #2) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 336 269.60 0.006 0.00 0.00 0.00 0.000 338 806.81 0.019 1,542.80 1,028.53 1,028.53 0.024 340 1,473.10 0.034 3,370.10 2,246.73 3,275.26 0.075 341 2,463.90 0.057 5,842.14 1,947.38 5,222.64 0.120 SWMBMPH (Foreb #3) Elevation (ft) Area (SF) Area (AC) Al+A2+(Al*A2)1/2 Volume (CF) Cumulative Volume (CF) Cumulative Volume (AC-ft) 336 30.10 0.001 0.00 0.00 0.00 0.000 338 387.40 0.009 525.48 350.32 350.32 0.068 340 881.90 0.020 1,853.81 1,235.87 1,586.19 0.036 341 1,727.70 0.040 3,843.97 1,281.32 2,867.52 0.066 Appendix C — VRRM Spreadsheets DEQ Virginia RunoffReducdon Method New Development Compliance Spmadsheet - Version 3.0 C 2021 BMP Standards and Specifications ID 2013 Draft BMP Standards and Specifications Project Name: Rivanna Village(PHI and lbi (Eng. &Planning dated 1/25/2019 daM trout celb Date: I 2-Mar-29 conznnt values BMP Design Specifications List 2013 Draft 5tds & Spea calculation cells Site Information Post -Development Project (Treatment Volume and Loads) Cover Parc./.Pan swce lacteal - undisturbed. PrnfeRed rorea/open spare or reforested land 22.34 2z3a Marugetl Turl (acres) - tllrturbed, traded for 36.26 Yards or mberrurtmbemawM/man M 36.26 Imorma us Were (actual 32.01 32.01 I eoresyrpmnporeoreos musrcepmrenmmoumoome wren me nrgmra xunop xmumon memoo (Constants Runoff Coefficients IRV) Annual Randall (inches) 03 Target Rainfall Ewnt(incbes) 1.an Total Phosphorus (TP)EMepni a26 Total Ntrogm(M) EMC]mg/L) 1.86 Target TP Load pb/acri 0.41 Pi lumdess mrreedi on face 0.90 ASolls lisais csoils DShcs Ferri spare 0.02 0.03 0.04 0.05 Managua Tort 0.15 0.20 0.22 0.25 Impervinm coven 0.95 0e5 0e5 0.95 FmeVVOpen Space Cover(acres) 22.30 Treat (aee-ft) a 3.2733 Treatment Volume (cubic feet) 162,5M Tic Wad(lb/yr) 89.59 Tel Wad (ib r) 600.89 Informational Purposes Onl Weighted RV(forert) 0.00 %Forest 25% Managed Turf Cover(accei 36.26 Weighted Rv (turf) 0.22 %Managed Turf CO% ImperfimsC er(acree) 32.01 Rv(ImperWous) 0.95 %ImperWous 35% Site Mea(anee) 90.61 Site RV a." DranaV Area DnaiAte ux A EARNI tmv'AN., S. P..m..ni. vanme EEC E. TURS AREA ED 111) Al. 1a1K DR. TREATED n4 EA1a1A Da roE ExxanESDxRDx,.DAA,x•, BeMI peMl miu vxouxanus n[xunixc nrrzx nrvui xc RUNOFF xsooviox vxuT[55 i x o.a n B WED . EREATENQWIEFFE M ......COM..EGINUTIONS —Al" 3.BOB xmaFOR REMOVED vmx Exxon Esmirnnx vExcncis IN Dn ABxAD Itest ONE AND. gwxnmmwaxn TAB raa nnDA I Dra nags Area B wAAAI ex CARE'x[rtx eu s. P..m..ni. P...me rzx PQ ax,Q wwa.Ca. ro.B,xx.B.FREDUCTION ,xBB ,IW IUU� TOTAL PHOSEHORUS AVAILABLE FOR REMOVAL IN <B BB/M <ePB/REI roar rxasrxovus Bemsix ms man ACCEDED xuxorr nrournax rnarncw ix oa a Byyx ... QUA"I OMC . TAB PoR.COM.E dlNL1TlON5 aBw wB xiaww mrBovEoww�xuxwrmoxrnax.nacncw ixoaBBB/w� am s w Mwu mmnwx¢TABr Sne CuWMT l�A ) Drainage Area C EACH IUAR r. P..m..ni. Panme m RARE TOTAL M PE VIOUC COVER FO an ,FO on 1 D 27 1 AREACHECR. OR mTAE RUNOFF RmUrnON IN R k C FRI)l FEAR TITAL FERMI AVAULABLE NOR REMOVAL IN CA. c BBryx ioiu PxosVEN nwnxs REMAINING AFTER APPINING RUNOFF REDUCTION Pc(I RnrncEs IN OA. c BBnx EEf WATER BWLIIYCBMPL1ANCf TAB PoRLif CBMMIANCf GINfATIOMF METAL RUNOFF FOURTEEN INDOE Fin .— xlmOOmREnmmwlm axxon--u--PRArncmlx B<C-1 ax FFF warzR qunury mnurax¢TAB Flv nn cuNuiwre' l�•leIAINx'� Lm yl Drainage Area B F-, n,,..) R. wmwaN,a,UN ars.Me...a....na n ..n aneReUNNUF v. UR wvM I. u,B(M I an SWrmwMer Bert Management Practices (RR = Runoff ReduCion) IF FOR mru MANAGED TURF Area, TREATED (.I)l U . I AREA ... In. mru RUNOFF REDUCTION IN UA, D IF) .....mi tsu ...am.EwwEow..—I uuacnoe vasmcE.i. —Bnwvl 1 7m sFF wlrtR u.mr mwa.[F me..11m1.. R.f.11lenoe P.M Drainage Area C wM..au..AMeer....l�al ChOd sire OUR S. Stormwater Best Management Practices (RR = Runoff Reduction( imal M DPph.... Pvailsele M, Removal In DA [IIB/ pen Melepment i,erzmam V 16me In O.A. [ (W) PraRice Ruma maitlzl C.ROQ M-AANJ,n e(.—A) laa:l I,ryervba ,u.an Am+laau vmumhen Ypu.am nma=IR'1 Rinert ReW�.iR� RamaWni MwX vem.m lR'1 DO, BM nammm vmmimlR'1 °p'° pneepliem• a eem m P ma.ilM U""" Im.Plnm. A, P mJmlel R—RABp Rv Rm.✓a llal MISS aapnuw oae lMl .tn.m r.an rasa a M•elev.d e"O11 Emaa.re Rl z u mzn lsremu) z, 1-2l,p—ul ,.".., —...n S'.L n A., a.....S'.aU, mlm Mai u. wnP.re m ylemi B o u o o :o um nm um om raanlumu.unilma,.i o o u o o .: um nm om om ts. wn P.re 12 is —ADS o sssa en: A u µxn µtn Ts um mul ms, tnvl a A B BLO Are om BLO A o B A B :o BLO Dre om BLO TOTAL tl� AAREA CHEC ON. TOruuwEA mVIOUS CARTRAUTEulaD(,i AREA exECR. ON. TOTAL PHOSPHORUS REMOVAL REQUIRED ON SITE DB/vI D AC::rTOTAL PHOSEPHORUA REMOVEDWITHOUT RUNOFF REDUCTION Ad1H/vI TOUH. PHOSPHORUS REMMED NOR RUNOFF TOTOPHOSPHOSEUS LOAD==EEDAQIyv1 achy •1 TOTAL PxomHDRus REMmHIxO AFTER APPLYING BMP LOAD REDUCTIONS IN D.A. c UWQ SEEWATER gUALI" nlHna UDDEHREMDVLOwITHDIm ABIMnn TOTALMORDDEH REMOV LO I H DA c nana REMARK, .,.Reaa U .mae No A Ra.,.mIny n,m'al A—UPm.am Payell L t R.me..tl LO BY B leatl Exe•a•.vlzl n—I,:i mmallB.le nmObD OMD OEM= ®®®® omo� om®mm moot o0mm� ,..., ... 0mo� �mmoo 0mo� mmmoo 0moo 0mo� o0moo 0mo� ommmm 0mo� ommmm 000� 00000 o��000000mmo� �o��0000mommo� �om�mommoomom� �o��0000mommo� .......... ,:.,�.:....o. mmmmo ®mmmm ommoo 00moo mm0mm ®m0mm ommmo ommmo o�mmm ommoo ommmm ommmm ommmm KID -pi Uralnage Area E wMERMAD. A and Carr lavl DOWTO,N, ama is Pr,arthan sire area! Evary yz"Lalaml10,73 w�mrtl�l 1.1 Stormwater Bert Management Practices (RR = Runoff ReaucBon( Rams Pbmpbnm, A.anaMa Mr Ramnal M DA F INnI Ran Daminpmma Rmaanma vnlnma In DA E IKI aalaa.tmm ananka-un.- pndice Wan. Reauatn Cmanlxl M.nyea Nrl [me�Anna laan I.omlm, .4eax Amal.�.l Vmumxmn 1q.umm rmaumlx'1 Runelf Uennbnlx'1 xamtlianR b velum Intl Ova, I. Te.emm .1-111) PMp Mnennm. m P mrcriibl N' n P —ta) PM.py— By Rmn'm ibl n4q nwm nnllbl nmmPrs ube Onwn Farylryea� alerv. Elac-Crou a. n. naylenal Dan n m ... xzlsce=.asl 11 :. i ."" l:v."I Sp-uazl ."" 1.1a2isP..u12l z. "nm n #I Onl B. P"mp10--i n p p p p sp pm nm pm pm n.wu Mmnls�urnnllsPaml 0 0 o p p a pm nm pm pm an. wnP.re pz ylemi o was zees o n anssp ax m zs pm ma3 Mm ziss n p n ss pm nm pm pm p o n p n M pm nm pm nm IMPERVIOUSTOTAL COVER rzDlay� AREA RarumaxUFORUEnC E D1.� EACHECK: OR. UM. RFOOIRFD OM END OW D AEOW .I MOVED WITHOUT RUNOFF REDUCT a C.:. AEllb/yrl AEII rl AEII rl WMW AFnR APPWW BMP LOM REDUCTIONS IN DA E l W,) SEEWATER gUALITY AEIIy .l aqM/yrl REMOVED IN DA F Ry D 25133 xmaan maanwa unnearm N. n Rama-1 e—upmmm Man,weu m mame By xa IUVd Fxlam..ylwl emle.l mumllb.l PDROUNRODO Ona urmaa, Area o„aMIANEW aDAF.WAVE 'FACE,. 1 RK, TOTAL M PE MOUC COVER rzo PQ TOTAL TURF AREA rzo 11Q uderx. FEE ro.a, RUNOFF REoUma.. DAC D JR ECE� IN „r r Qr .a�.�SR.xxa,.GAREa.PP,INGaU.or.a.DURION OMPHRODUS REMOVED WITH RUNOFF REDUCUTFUN FACURE,IND—JaVEN ... QQaLQY romauxcc rae wa me romniaxcc u,rounoxs .AHE) nu aaaw� a.aaf REVEaaaRUNOFFHINUQ..a.ro1E„NRRUNOFF DEDUCTION 1.UCA"aa, . warza Quaurvromruaxn raa roa sin EACEWAwro'olarl Dralnage Area A wanpN,A unN m..• la¢.e snm/gmspaelaml wn mn."—1 In,-1.1 Stormwater Bert Management PnRices (RR = Runoff Reductlun( idol PM,pMrv, Anllabk ON Remwf In F.A. A OWH Pnn@u,kP¢,MTUALMAL Vul¢¢k DA A IX'1 hk¢tmm dnUpAA Tlbw Pndice wn Rein c¢Nxl%1 MUHRUNTurf .Na k>rn rrymyAK rtnet A¢,k>r,l vm¢¢x¢n UNFAUm NrN¢Ib'1 R.nWf RMunbnlx'1 xemtlMnR .. vel¢¢IX'1 Own, N. Te.n¢m vel¢¢Ix'1 PlwPlerv, 1 "A"'nm m P CT_ n,. n P U,A(Rl PRmPRnn,. MHE x,r¢'¢OM nng nwu ¢nllq w.beUIWOK" .m MxN ¢be Rm Ema¢ry1%1 IL. . n. nrylennANT n .....,S,. PLO - -IS 11 :. i ."" r.v."I Sp- #12) ."" r.v..ez lsP..urzl z. "um n #I nsl ."n.v .r. Ya P"wn(,P--, o o a n o :o am nm ANT om n.Nwmnl�¢rubllsPRm1 0 0 0 0 o a om nm om om .,. wnIn.Pzglsal o n a n o ,. am Am nm om _en—nt—p-Ms U.) o 0 0 0 o ss om nm om om 0 A o xo om nm om nm TOTAL IMPERVIE-Un � a TOEumufaGEDTU CORCEIR DI,A EATREATED Ian AREA CHECK: OR. REM. REpu REO4191E OWH TOUTALLPHOESPHORIUSAIUALANNEIGR=OVA Al a AIIy .l A . AIM/nl mrxasxx .aa AAOIyy.l MEAN. PHOSPHORUS RUN CHSE� NO TOTAL PHOSPHORUS REMAINING AFTER APPLYING ANE LOAD REDUCTIONS IN D.A. A OWH SEE WATER QUALITY NOR EN RE�DWI� RUNOFF REDUCTO Al AAOW •1LET xITROGEN REMOVED WITHOUTAAllb/nl MIT TOTAL XXROGEX REMOVED 1N nA A O WY•1 1101 XMa, ¢a,nwe anD„¢X Xlba,n Ing mr,l f.nnn UESSAN¢ MON,weM Innr¢,e By X „ln,a P ExRknrylxl ,Iwl ,nI¢Ilbn -ObO MAgObO Bralnage Area B Rnanpu.. A vnatwe, lMWA snm/gmspaelaml wrgmiuRl�nl inul Stormwater Bert Management Pmakes (RR = Runoff Reaucton( 1.1 Pxaspxn RVERAk fv 2emwf In xA 2 RAfNu 3A Pra. Re✓.tpmw[ Tewnen. W—In aA B Bs'1 I was hkntmm dnUWW Tlxw practice 0.uwn Reau.n emanlzl m.nyea Tnl [me�DOW 1.�.1 "WRE .teat m.a4>r.1 vmuTxen Rpw..m w+w=IR'1 R nnlr RMunbnlx'1 Rem.4an2 b� veluce Intl Tom W. Te°mmm velw.lx'1 PMPIerv. I mnennm. m p nip•iim N' n P woaniim Pln.p� . Rv pmn' lal R.mEn4q pnmpnvur etl IIRI nm.mpN on 0.wn 4ryley.aw FUaenxou :. n. nslslenn m ... xzlsce=.ssl - sfx 11 :. i ."" 1.1-1 Sp-uszl ."" 1.1a2isP..u12l z. "nm n #Is nsl lsP uIl E3,.wn P"m.EgPRx,a o o a n o :o am ram om n.wnmmnls�drnnllsPnml 0 0 0 0 o a om ram om om u. In. ez glami o 0 n 0 r 11 "M ram om om -wnma-(—P-)(n ,U) 0 0 n 0 r ss "M ram om om n 0 r xo om ram om nm TOTALIMPERVIE-URCOREIRTHERENED(n) AREA 2arumxU xER2UREA2EA2rtEA2Fpl.tl EAOIECR. W. Umtvu RF.RWD ax sm UW,) 0 AeII nl WORK. PHEREPHORM REMOVED WITHOUT RUNOFF REDUCT C.:. AeII nl m2u PxmP ABIIx/nl TOTALPHODEPIKHRUS LORDABUW Bmurxxspxt2us RFmuxlxB AnFRAPPmxR amPm saFUNCTIONS IN pAeaWvr).l SEEWATER gUALI" MOR IN REMOVED WITH RUNOFF RIFIDUCT A B uIlNt,0 TO n WFx RFmxwa WITHOUT emuNIMO Ex REmWERIxpABaxn.l Drainage Area C P•FyN• A I•MCme, lavl snm/gmspvlaml wrgm iuRlmevl inul Stormwater Best Management Practices (RR = Runoff Reducton( TONI Pbmpbnrvx AWEIGH• ARE Remw•I In DA C Ia/ytl R9R AREA Melnpment TIMrzm•m Vtlum• In RA C ni I R.RTI hkMRE. ampanw11— Pndice Ruwn Reau.n C.ax IHI GFURNMEW! [.MBA.• 1•>rn RNMORD, .4eax A.al•>r•1 Wun-a— Lq.MM•m REEMam Intl FILE. RMa..bnlx'1 km.IMnR b� vMw. lx'1 Rty,I. Tm•mmm VMw.lxj rMp I .."PRO. End RR. m p mp•iiM GI n P woaniIn) Pbmp� • Ry PMODEF lbl R-RIn4q Pnmpnvur etl RN n.•mLOVE Ube Dpwn WER •lerv• EBd-OBLl a. n. ntylenn m w..IED'. uul - - L, ;sn 11 :. i ."" m—I Sp-ual ."" mvamisP..ual z. "ram— —Enn #I s NU ."nmv m. P, W-tltn tE,.w., P"magp.Mal D D D n D :D Dm ram ram Dm n. LV.�mmnlL�ureXllsPa M'ul o o p p p a pm ram pm pm �. wnIn.12 —, D n D n D 11 Dm ram pm Dm _--VE—P-)(Wmtlm) p o E o R ss pm ram pm pm Lca_M '/xKr�mnamiM `" C"" p o E A R 2A pm ram pm pm METAL dtl� a Tmuma PERVIOUS COVEATREATEEDD p� EACX[CX. OR. REMOVAL REQUIRED ON BUT OWD .0.CIIb/y.l .0.[Ilb/y.l iLILAL PIMHX .0.[Ilb/y.l QYEALPHOESPHORRIES L WOYIgRUR REMNHIXG AFTER APPLYING DUMP LOAD REOUCTOXE IN D.A. C IlWD SEE WATER gUALI" COMPLIANCE TAB FOR SITECOMPLIANCE CALCULATIONS A.c IIb/y.lOUR HHRZEXREMOVED WHXOVf .0.[Ilb/y.l 1. ttR NIX EHREMMEOIXDACIlb/y.l Ntyry. Anyonnumil unoM•ma N. n REPIROVII L m n Upm.•RE LE.em m e.o.Ma By NU Lma EMelenry�%1 ¢Ye•IMI •N.IIb•1 -(BG Ilb•1 Dralnage Area D Dmnwr., A Mna CA- GGEM) snm/gmspaelaml wrgmiuRl�l inul Stormwater Bert Management Practices (RR = Runoff Reauctlun( TANI PTA PMD, Ar.II.bI. M. R.mwN In DAD 11 b/yD PIA D..elnpm.nt TA—Vt VMum, In DA D GO) I Am hEKT..DWHAMT11— preoce W-11 ReWutn C.an 1%1 GN-AWNrl [.e�A.. 1.ON, "AND .Onax ROR AV, VmuT a— URPOW-m WWQ_(x') RnM R.a..Innlx'1 RERVIENR b. vel.i. Intl no, I. TQW-nt velw.lx'1 GNAMNAua 1 ra-H'nm. m P mOn N' n P wAIII) PIn.PMNAma Ry RwnI.IIM n4q nwu wnllq n..mPN ube Gewn Enaley.aw GAMMON) :. n. ntylenn Ann n m ... xzlsce=.ul - s^n ."" 1.1-2lsP-12) z. "nm n uyspaetsl ""n.v n: xz IW-u1 ta..wn P"metglFml r 0 0 A o so om nm Ann om n. LV.mmnls�urbXllsPRL'ul 0 0 0 0 o a om nm Annom u. wnP"mezglaml 0 0 U 0 r 11 om nm Annom _n'v.a+W ls�urbXllsP�PtO 0 0 U 0 r ss om nm om om 0 0 U A r G om nm om om L TOELLIMPER DTUSCMEATREATEDI.tlI 1117 AREA CHECK: ON. REMOVAL REQUIRED ON en OW D .a Dllb/y.l A DIIb/y.l TOPAL PIgRPX .&DIIb/y.l 0. DII .l IOTLL MOYIgR11R REMAI HIM AFTER APPLYING PUMP LOAD REDUCTIONS I H D.A DllWD SEEWATER gUALI" A DIIb .l0 in NTEROGEH MAGOVEDWITXOUT ADllb/y.l TOTAL NITROGEN REMOVED IN D.A. 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MR.. aulY[oMPo .CerEAR DR. 0.. /InrymvlM Dow Appendix D — Erosion and Sediment Control Data Sed Basin Il Sed Basin I2 Table of Contents Outlet Input Data, 25 years Outlet Input Data, 25 years Subsection: Outlet Input Data Label: Sed Basin I1 Requested Pond Water Surface Elevations Minimum (Headwater) 336.00 ft Increment (Headwater) 0.10 ft Maximum (Headwater) 345.00 ft Return Event: 25 years Storm Event: 25-YR Outlet Connectivity Structure Type Outlet ID Direction Outfall El E2 (ft) (ft) Stand Pipe Riser - 1 Forward Culvert - 1 341.00 345.00 Orifice -Circular Orifice - 1 Forward Culvert - 1 340.00 345.00 Culvert -Circular Culvert - 1 Forward TW 338.00 345.00 Rectangular Weir Weir - 1 Forward TW 342.00 345.00 Tailwater Settings Tailwater (N/A) (N/A) Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack val 005_1h2esc_20180131.ppc Center [08.11.01.561 2/27/2018 27 Siemon Company Drive Suite 200 W Page 1 of 9 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Outlet Input Data Label: Sed Basin I1 Structure ID: Riser - 1 Structure Type: Stand Pipe Number of Openings 1 Elevation 341.00 ft Diameter 36.0 in Orifice Area 7.1 ft2 Orifice Coefficient 0.600 Weir Length 9.42 ft Weir Coefficient 3.00 (ft^0.5)/s K Reverse 1.000 Manning's In 0.000 Kev, Charged Riser 0.000 Weir Submergence False Orifice H to crest False Bentley Systems, Inc. Haestad Methods Solution 005_1h2esc_20180131.ppc Center 2/27/2018 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Return Event: 25 years Storm Event: 25-YR Bentley PondPack Val [08.11.01.56I Page 2 of 9 Subsection: Outlet Input Data Label: Sed Basin I1 Structure ID: Culvert- 1 Structure Type: Culvert -Circular Number of Barrels 1 Diameter 24.0 in Length 50.00 ft Length (Computed Barrel) 50.00 ft Slope (Computed) 0.010 ft/ft Outlet Control Data Manning's In 0.013 Ke 0.900 Kb 0.012 Kr 0.000 Convergence Tolerance 0.00 ft Inlet Control Data Equation Form Form 1 K 0.0340 M 1.5000 C 0.0553 Y 0.5400 TI ratio (HW/D) 1.258 T2 ratio (HW/D) 1.420 Slope Correction Factor -0.500 Use unsubmerged inlet control 0 equation below T1 elevation. Use submerged inlet control 0 equation above T2 elevation In transition zone between unsubmerged and submerged inlet control, interpolate between flows at T1 & T2... Return Event: 25 years Storm Event: 25-YR T1 Elevation 340.52 ft T1 Flow 15.55 ft3/s T2 Elevation 340.84 ft T2 Flow 17.77 ft3/s Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack val 005_1h2esc_20180131.ppc Center [08.11.01.56I 2/27/2018 27 Siemon Company Drive Suite 200 W Page 3 of 9 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Outlet Input Data Return Event: 25 years Label: Sed Basin I1 Storm Event: 25-YR Structure ID: Orifice - 1 Structure Type: Orifice -Circular Number of Openings 1 Elevation 340.00 ft Orifice Diameter 6.0 in Orifice Coefficient 0.600 Structure ID: Weir- 1 Structure Type: Rectangular Weir Number of Openings 1 Elevation 342.00 ft Weir Length 10.00 ft Weir Coefficient 3.00 (ft^0.5)/s Structure ID: TW Structure Type: TW Setup, DS Channel Tailwater Type Free Outfall Convergence Tolerances Maximum Iterations 30 Tailwater Tolerance 0.01 ft (Minimum) Tailwater Tolerance 0.50 ft (Maximum) Headwater Tolerance 0.01 ft (Minimum) Headwater Tolerance 0.50ft (Maximum) Flow Tolerance (Minimum) 0.001 ft3/s Flow Tolerance (Maximum) 10.000 ft3/s Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack val 005_1h2esc_20180131.ppc Center [08.11.01.56I 2/27/2018 27 Siemon Company Drive Suite 200 W Page 4 of 9 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Outlet Input Data Label: Sed Basin I2 Requested Pond Water Surface Elevations Minimum (Headwater) 346.50 ft Increment (Headwater) 0.10 ft Maximum (Headwater) 355.00 ft Return Event: 25 years Storm Event: 25-YR Outlet Connectivity Structure Type Outlet ID Direction Outfall El E2 (ft) (ft) Stand Pipe Riser - 1 Forward Culvert - 1 352.80 355.00 Orifice -Circular Orifice - 1 Forward Culvert - 1 350.80 355.00 Culvert -Circular Culvert - 1 Forward TW 348.30 355.00 Rectangular Weir Weir - 1 Forward TW 353.00 355.00 Tailwater Settings Tailwater (N/A) (N/A) Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack val 005_1h2esc_20180131.ppc Center [08.11.01.561 2/27/2018 27 Siemon Company Drive Suite 200 W Page 5 of 9 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Outlet Input Data Label: Sed Basin I2 Structure ID: Riser - 1 Structure Type: Stand Pipe Number of Openings 1 Elevation 352.80 ft Diameter 36.0 in Orifice Area 7.1 ft2 Orifice Coefficient 0.600 Weir Length 9.42 ft Weir Coefficient 3.00 (ft^0.5)/s K Reverse 1.000 Manning's In 0.000 Kev, Charged Riser 0.000 Weir Submergence False Orifice H to crest False Bentley Systems, Inc. Haestad Methods Solution 005_1h2esc_20180131.ppc Center 2/27/2018 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Return Event: 25 years Storm Event: 25-YR Bentley PondPack Val [08.11.01.56I Page 6 of 9 Subsection: Outlet Input Data Label: Sed Basin I2 Structure ID: Culvert- 1 Structure Type: Culvert -Circular Number of Barrels 1 Diameter 18.0 in Length 32.00 ft Length (Computed Barrel) 32.00 ft Slope (Computed) 0.009 ft/ft Outlet Control Data Manning's In 0.013 Ke 0.500 Kb 0.018 Kr 0.000 Convergence Tolerance 0.00 ft Inlet Control Data Equation Form Form 1 K 0.0098 M 2.0000 C 0.0398 Y 0.6700 TI ratio (HW/D) 1.156 T2 ratio (HW/D) 1.302 Slope Correction Factor -0.500 Use unsubmerged inlet control 0 equation below T1 elevation. Use submerged inlet control 0 equation above T2 elevation In transition zone between unsubmerged and submerged inlet control, interpolate between flows at T1 & T2... Return Event: 25 years Storm Event: 25-YR T1 Elevation 350.03 ft T1 Flow 7.58 ft3/s T2 Elevation 350.25 ft T2 Flow 8.66 ft3/s Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack val 005_1h2esc_20180131.ppc Center [08.11.01.56I 2/27/2018 27 Siemon Company Drive Suite 200 W Page 7 of 9 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Outlet Input Data Return Event: 25 years Label: Sed Basin I2 Storm Event: 25-YR Structure ID: Orifice - 1 Structure Type: Orifice -Circular Number of Openings 1 Elevation 350.80 ft Orifice Diameter 6.0 in Orifice Coefficient 0.600 Structure ID: Weir- 1 Structure Type: Rectangular Weir Number of Openings 1 Elevation 353.00 ft Weir Length 10.00 ft Weir Coefficient 3.00 (ft^0.5)/s Structure ID: TW Structure Type: TW Setup, DS Channel Tailwater Type Free Outfall Convergence Tolerances Maximum Iterations 30 Tailwater Tolerance 0.01 ft (Minimum) Tailwater Tolerance 0.50 ft (Maximum) Headwater Tolerance 0.01 ft (Minimum) Headwater Tolerance 0.50ft (Maximum) Flow Tolerance (Minimum) 0.001 ft3/s Flow Tolerance (Maximum) 10.000 ft3/s Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack val 005_1h2esc_20180131.ppc Center [08.11.01.56I 2/27/2018 27 Siemon Company Drive Suite 200 W Page 8 of 9 Watertown, CT 06795 USA +1-203-755-1666 Index Sed Basin Il (Outlet Input Data, 25 years) ... 1,2,3,4 Sed Basin I2 (Outlet Input Data, 25 years) ... 5, 6, 7, 8 Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_1h2esc_20180131.ppc Center [08.11.01.561 2/27/2018 27 Siemon Company Drive Suite 200 W Page 9 of 9 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Catchments Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (k3/s) (years) (ark) SB-Il Post -Development 1- 1 2.052 11.920 38.10 SB-Il Post R -Development 2- 2 2.640 11.920 48.46 Sl Post -Development 10 10 4.408 11.920 78.67 Sl Post -Development 25 25 5.611 11.920 98.70 Sl Post -Development 100 7.802 11.920 134.57 100-YR SB-I2 Post R -Development 1- 1 1.033 11.920 19.18 SB-I2 Post R -Development 2- 2 1.329 11.920 24.39 SB-I2 Post -Development 10 10 2.219 11.920 39.60 SB-I2 Post -Development 25 25 2.825 11.920 49.68 SB-I2 Post -Development 100 3.927 11.920 67.74 100-YR Node Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event volume (hours) (k'/s) (years) (ark) 0-SBIl Post R -Development 1- 1 1.849 12.040 22.83 0-SBIl Post R -Development 2- 2 2.398 12.040 30.57 0-SBI1 Post -Development 10 10 4.083 12.020 57.84 0-SBI1 Post -Development 25 25 5.268 12.010 75.80 0-SM Post -Development 100 7.446 11.990 108.03 100-YR 0-SBI2 Post R -Development 1- 1 0.986 12.040 12.48 0-SBI2 Post R -Development 2- 2 1.276 12.000 19.56 0-SBI2 Post -Development 10 10 2.146 11.960 35.43 0-SBI2 Post -Development 25 25 2.727 11.960 44.34 0-SBI2 Post -Development 100 3.776 11.960 61.06 100-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPack V8i 005_1h2esc_20180131.ppc Center [08.11.01.561 2/27/2018 27 Siemon Company Drive Suite 200 W Page 1 of 3 Watertown, CT 06795 USA +1-203-755-1666 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Event Volume (hours) (fta/S) (years) (ac-ft) Maximum Maximum Water Pond Storage Surface (ac-ft) Elevation (ft) Post- SB-Il (IN) Development 1 2.052 11.920 38.10 (N/A) (N/A) 1-YR Post- SB-Il (OUF) Development 1 1.849 12.040 22.83 341.99 1.825 1-YR Post- SB-Il (IN) Development 2 2.640 11.920 48.46 (N/A) (N/A) 2-YR Post- SB-Il (OUF) Development 2 2.398 12.040 30.57 342.35 1.965 2-YR Post- SB-Il (IN) Development 10 4.408 11.920 78.67 (N/A) (N/A) 10-YR Post- SB-Il (OtfF) Development 10 4.083 12.020 57.84 343.03 2.233 10-YR Post- SB-Il (IN) Development 25 5.611 11.920 98.70 (N/A) (N/A) 25-YR Post- SB-Il (OtfF) Development 25 5.268 12.010 75.80 343.37 2.374 25-YR Post- SB-Il (IN) Development 100 7.802 11.920 134.57 (N/A) (N/A) 100-YR Post- SB-Il (OUF) Development 100 7.446 11.990 108.03 343.90 2.599 100-YR Post- SB-I2 (IN) Development 1 1.033 11.920 19.18 (N/A) (N/A) 1-YR Post- SB-I2 (OUF) Development 1 0.986 12.040 12.48 353.22 0.891 1-YR Post- SB-I2 (IN) Development 2 1.329 11.920 24.39 (N/A) (N/A) 2-YR Post- SB-I2 (OtfF) Development 2 1.276 12.000 19.56 353.36 0.916 2-YR Post- SB-I2 (IN) Development 10 2.219 11.920 39.60 (N/A) (N/A) 10-YR Bentley Systems, Inc. Haestad Methods Solution 005_1h2esc_20180131.ppc Center 2/27/2018 27 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Bentley Pondl V8i [08.11.01.561 Page 2 of 3 Subsection: Master Network Summary Pond Summary Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum Event Volume (hours) (ft3/S) Water Pond Storage (years) (ac-ft) Surface (ac-ft) Elevation (ft) Poi SB-I2 (OUF) Development 10 2.146 11.960 35.43 353.68 0.977 10-YR Poi SB-I2 (IN) Development 25 2.825 11.920 49.68 (N/A) (N/A) 25-YR Poi SB-I2 (OUF) Development 25 2.727 11.960 44.34 353.89 1.019 25-YR Poi SB-I2 (IN) Development 100 3.927 11.920 67.74 (N/A) (N/A) 100-YR Poi SB-I2 (OUF) Development 100 3.776 11.960 61.06 354.24 1.088 100-YR Bentley Systems, Inc. Haestad Methods Solution Bentley PondPecl( vat 005_1h2esc_20180131.ppc Center [08.11.01.561 2/27/2018 27 Siemon Company Drive Suite 200 W Page 3 of 3 Watertown, CT 06795 USA +1-203-755-1666 Appendix E — Example Deed Restrictions and blainntenance Agreements This document was prepared by: Albemarle County Attorney County of Albemarle 401 McIntire Road Charlottesville, Virginia22902 Tax Map and Parcel Number XXXXX-XX-XX-XXXXX This deed is exempt from taxation under Virginia Code §§ 58.1-811(A)(3). DEED OF DEDICATION AND EASEMENT THIS DEED OF EASEMENT is made this _ day of DATE by and between XX Grantors, and the COUNTY OF ALBEMARLE, VIRGINIA, a political subdivision of the Commonwealth of Virginia, Grantee. WITNESS: WHEREAS, the Grantors are the owners of that certain real property (hereinafter the "Property") located in Albemarle County, Virginia, more particularly described as follows ADD PROPERTY DESCRIPTION WHEREAS, the Grantors seek to dedicate for public use those portions of the Property shown as "Plat Showing SWM Forest and Open Space Easement' shown on the plat of PLAT E BY WHOM, a copy of which is attached hereto to be recorded with this deed (hereinafter, the "Easement" and the "Plat"). Reference is made to the Plat for a more particular description of the easement conveyed herein; and WHEREAS, the Grantors and the Board of Supervisors of Albemarle County, Virginia have entered into an agreement entitled "Stormwater Management Facilities Maintenance Agreement" (hereinafter, the "Maintenance Agreement"), a fully executed copy of which is attached to this deed as Exhibit A, in which the Grantors have agreed to construct and maintain on -site stormwater managementBMP facilities; and WHEREAS, the Maintenance Agreement provides in part that the Grantors give permission to the County, including its authorized agents and employees, to enter upon the Property and to inspect the stormwater management/BMP facilities whenever the County deems necessary; and the Maintenance Agreement also provides in part that, in the event the Grantors, its successors and assigns, fails to maintain the stormwater managementBMP facilities in good condition acceptable to the County, the County may enter upon the Property and take whatever steps necessary to repair or otherwise maintain the facilities and to otherwise correct deficiencies. Version: 11/25/14 WHEREAS, it is the desire and intent of the Grantors to dedicate, grant and convey an Easement for public use in accordance with this Deed of Dedication and Easement. NOW, THEREFORE, in consideration of the premises and TEN DOLLARS ($10.00), cash in hand paid, and other good and valuable consideration, the receipt of which is hereby acknowledged, the Grantors do hereby GRANT, CONVEY, and DEDICATE to public use with GENERAL WARRANTY and ENGLISH COVENANTS OF TITLE unto the Grantee, its successors and assigns, a perpetual easement as shown on the Plat and as referred to herein as the Easement. The Easement shall be subject to the following: 1. Right of ingress and egress. The Grantee and its authorized agents and employees shall have the right and easement of ingress and egress over the Property to perform all acts to which the parties have agreed it may perform under the Maintenance Agreement. 2. Ownership of the facilities. The stormwater managementBMP facilities required to be constructed and maintained by the Grantors under the Maintenance Agreement shall be and remain the property of the Grantors. This Deed of Dedication and Easement shall not be construed to be an assumption of ownership or control by the Grantee over the stormwater managementBMP facilities subject to the Maintenance Agreement. 3. No obligation on Grantee to inspect or maintain. This Deed of Dedication and Easement shall not be construed as imposing an obligation on the Grantee to repair or otherwise maintain the stormwater management/BMP facilities subject to the Maintenance Agreement. 4. Grantee's right to assign. The Grantee shall have the right to assign this Easement as its interests may require. 5. Binding effect. The Easement and the rights and obligations established herein shall run with the land in perpetuity, and shall be binding upon the Grantors, the Grantee, and their successors and assigns. All references herein to the "Grantors" and the "Grantee" include their respective successors and assigns. All references to the "Grantee," when exercising any right or obligation herein, includes the Grantee's officers, employees and agents. The Grantee, acting by and through its County Executive, duly authorized by resolution adopted by the Board of Supervisors of the County of Albemarle, Virginia, accepts the conveyance of this property pursuant to Virginia Code § 15.2-1803, as evidenced by the County Executive's signature hereto and the recordation of this Deed. 2 Version: 11/25/14 WITNESS the following signatures. M T.W"" By: NAME By: NAME COMMONWEALTH OF VIRGINIA CITY/COUNTY OF The foregoing instrument was acknowledged before me this _ day of DATE, 2018 by NAME. Notary Public My Commission Expires: Registration number: GRANTEE: COUNTY OF ALBEMARLE, VIRGINIA Thomas C. Foley County Executive Version: 11/25/14 COMMONWEALTH OF VIRGINIA CITY OF CHARLOTTESVILLE: The foregoing instrument was acknowledged before me this _ day of by Thomas C. Foley, County Executive, on behalf of the County of Albemarle, Virginia, Grantee. My Commission Expires: Registration number: Approved as to form: County Attorney Notary Public 4 Version: 11/25/14 This document was prepared by: XX XX XX Tax Map Parcel: XX=-XX-XX-XXXXX TO MAINTAIN STORMWATER MANAGEMENT FACILITIES AND OTHER TECHNIQUES THIS AGREEMENT is entered into by and between NAME, hereinafter called the "Owner," and the COUNTY OF ALBEMARLE, VIRGINIA, a political subdivision of the Commonwealth of Virginia, hereinafter called the "County." RECITALS R-1. The Owner is the fee simple owner of certain real property described as Albemarle County Tax Map Parcel #, and more particularly described in a deed to Owner dated XX and recorded in the Clerk's Office of the Circuit Court of Albemarle County, Virginia, in Deed Book XY, page XX, hereinafter called the "Property"; and R-2. The Owner is proceeding to build on and develop the Property and XX; and R-3. The Property is within the County's Municipal Separate Storm Sewer System (hereinafter, "MS4'� jurisdictional area, and R-4. The Site Plan identified as SDP 2018- was approved and, in conjunction therewith, a Stormwater Management Plan, identified as WPO-2018- , hereinafter called the "Plan," which is expressly made a part hereof, as approved or to be approved by the County, and which provides for the detention and water quality treatment of stormwater within the confines of the Property, and R-5. The Plan and the land disturbing activity related thereto are subject to the Virginia Stormwater Management Act (Virginia Code § 62.1-44.15:24 et seq.), as implemented in part by Chapter 17, Water Protection, of the Albemarle County Code; and R-6. 9VAC25-870-112 and Albemarle County Code § 17-415 require the Owner and the County to enter into this agreement in order to ensure the long-term maintenance of the permanent stormwater management facilities and/or other techniques required to serve the Property and, for those facilities within the County's MS4 jurisdictional area, 9VAC25-890-40 imposes additional requirements, and the County implements 9VAC25-870-112 and 9VAC25-890-40 through Version: 01/17/17 Albemarle County Code § 17-415 and this Agreement; and R-7. For those facilities within the County's MS4 jurisdictional area, this Agreement also addresses, in part, the County's obligations under Minimum Control Measure Number 5 (post - construction stormwater management) in the Albemarle County 5-Year MS4 General Permit and Program Plan; and R-8. Albemarle County Code § 17-415 requires that permanent on -site stormwater management facilities and/or other techniques, as shown on the Plan, including all pipes and channels built to convey stormwater to and from the facilities, all structures, berms, inlet and outlet structures, pond areas, filtration media, and forested and open space areas (which are considered to be a nonstructural technique to meet stormwater management requirements), provided to control the quantity and quality of the stormwater, access roads, and any other improvement that may affect the proper functioning of the Facilities (hereinafter, "stormwater management facilities and other techniques" are referred to individually as a "Facility" and collectively the "Facilities' be constructed and adequately maintained by the Owner in perpetuity. In consideration of the foregoing premises, the mutual covenants contained herein, and the following terms and conditions, the parties hereto agree as follows: 1. Obligation of the Owner to construct the Facilities. The Owner shall construct and protect the Facilities that are required to be constructed, and shall do so in accordance with the Virginia Stormwater Management Act plans and specifications identified in the Plan. 2. Obligation of the Owner to maintain the Facilities. The Owner shall maintain the Facilities in good working condition for so long as the Facilities exist, in a manner that meets or exceeds the maintenance standards provided herein, subject to the following: A. "Good working condition" defined. For the purposes of this Agreement, a Facility is in "good working condition" when it performs its design function in accordance with the plans and specifications identified in the Plan, including all conditions imposed in conjunction with approval of the Plan, and complies with all applicable statu, as determined by the Albemarle County Engineer (hereinafter, the "County Engineer'. B. "Maintain and maintenance" defined. For the purposes of this Agreement, "maintain" and "maintenance" include, but are not limited to maintaining, repairing, replacing, reconstructing, preserving, and restoring the Facilities or any part thereof necessary to comply with the plans and specifications identified in the Plan. C. Maintenance schedule. The Owner shall maintain the Facilities in compliance with the 2 Version: 01/17/17 maintenance schedule in the approved Plans as required under Albemarle County Code § 17- 403(A)(5). D. Professional engineer may be required to direct work The County Engineer may require that specific maintenance work be performed under the direction of a professional engineer. 3. Inspections and the Inspection Report by the Owner. The Owner shall have the Facilities inspected to ensure that the Facilities are in good working condition, subject to the following: A. Who may inspect the Facilities. The Facilities shall be inspected by the Owner or upon written demand by the County Engineer by a person who: (1) is licensed as a professional engineer, architect, landscape architect, or land surveyor pursuant to Virginia Code § 54.1-400 et seq.; (2) works under the direction and oversight of the licensed professional engineer, architect, landscape architect, or land surveyor referenced in subsection (A)(1); or (3) who holds an appropriate certificate of competence from the State Water Control Board. B. What must be inspected. The inspections shall be conducted according to the requirements of 9VAC25-870, et seq. or as that section is hereafter amended. C. When inspections shall be conducted. The Facilities shall be inspected as specified in the approved Plans or by the County Engineer. D. What documents must be maintained. The inspection shall be documented on a form provided by the County Engineer and shall be completed to the satisfaction of the County Engineer (hereinafter, the "Inspection Report'. At a minimum, the Inspection Report shall provide, as applicable, the date of the inspection, the name of the inspector, a description of the condition of all pipes and channels built to convey stormwater to and from the facilities, all structures, berms, inlet and outlet structures, pond areas, filtration media, forested and open space, vegetation provided to control the quantity and quality of the stormwater, access roads, and any other improvement that may affect the proper functioning of the Facilities, a list of all deficiencies causing the Facilities not to be in good working condition, including all control measures not operating effectively and all control measures that are inadequate, a list of required maintenance work to be performed so that the Facilities are restored to good working condition, and the date by which the maintenance work will be performed. E. To whom and when an Inspection Report must be submitted. The Owner shall submit the Inspection Report and any other requested inspected documentation to the Director, Albemarle County Department of Facilities and Environmental Services, 401 McIntire Road, Version: 01/17/17 Charlottesville, Virginia 22902 or a successor department, office and address delineated by the County to the Owner. The Owner shall provide the Inspection Report to the Department within thirty (30) days after completion of the inspection. F. Section 3 satisfied if County conducts inspection in any_yea r. The Owner's obligation to have the Facilities inspected and to submit an Inspection Report under Section 3 shall be deemed to be satisfied in any inspection period in which the County conducts an inspection under Section 4 and as provided in Albemarle County Code § 17-811. G. Inspection Period defined. For the purposes of this Agreement, inspection period means the one-year period beginning and ending on the anniversary of the date of this Agreement first hereinabove written. 4. Permission to the County to inspect the Facilities. The Owner hereby grants permission to the County, including its authorized agents and employees, to enter upon the Property and to inspect the Facilities whenever the County deems an inspection to be necessary, subject to the following: A. Purposes for County inspection. The County may inspect the Facilities for the purpose of determining the condition of the Facilities including, but not limited to, determining whether the Facilities are in good working condition, investigating any deficiencies reported in the Inspection Report, responding to citizen complaints about the Facilities, and inspecting or observing any maintenance of the Facilities. B. Prior notice to the Owner not required. The County shall not be required to provide prior notice to the Owner to enter the Property to conduct the inspection. C. Inspection findings and demand for maintenance. The County shall provide the Owner with a copy of the findings of its inspection of the Facilities. If the inspection concludes that maintenance of any of the Facilities is required, the County also shall provide the Owner with a demand that the Owner maintain the Facilities and the date by which the maintenance work must be completed. 5. The Owner's response to the Inspection, the Inspection Report or the Countv's demand for maintenance. The Owner shall comply with the following: A. Corrective action. If the inspection identifies the need for a corrective action, it shall be completed as follows: (i) if an inspection identifies a Facility that is not operating effectively, the Owner shall complete corrective action as soon as practicable, but no later than seven (7) days after discovery or a longer period allowed in writing by the County Engineer, (ii) 4 Version: 01/17/17 if an inspection identifies an existing Facility that needs to be modified or if an additional control measure is necessary, implementation shall be completed prior to the next anticipated measureable storm event, if implementation before the next anticipated measureable storm event is impractical, then it shall be implemented no later than seven (7) days after discovery or a longer period allowed in writing by the County Engineer. The term "control measure" means any best management practice or stormwater facility, or other method used to minimize the discharge of pollutants to State waters, or otherwise restrict or alter the hydraulics of stormwater flow and discharge. B. Maintenance. If the Inspection Report under Section 3 or the inspection conducted by the County under Section 4 identifies Facility deficiencies, the Owner shall promptly complete the maintenance work by the date specified in the Inspection Report or as demanded by the County. When the maintenance work is completed, the person performing or directing the work shall certify to the County that the Facilities are in good working condition. 6. Right of the County to enter the Properly to maintain the Facilities. If the Owner fails to maintain the Facilities in good working condition as required by Section 2 or fails to complete timely maintenance work as required by Section 5, the County, including its authorized agents and employees, may enter upon the Property and take whatever steps necessary to bring the Facilities into good working condition and to otherwise correct all deficiencies identified in the Inspection Report under Section 3 or the inspection conducted by the County under Section 4, subject to the following: A. No right to erect permanent structures; exceptions. The County's right to take "whatever steps necessary" shall not be construed to allow the County to erect any structure of a permanent nature on the Property unless: (1) the structure is required to ensure that the Facilities perform their design functions; or (2) it is a structure to house equipment to monitor the Facilities and any fencing related thereto. B. County not obligated to maintain the Facilities. It is expressly understood and agreed that the County is under no obligation to repair or otherwise maintain the Facilities, and in no event shall this Agreement be construed to impose any such obligation on the County. 7. Right of the County to charge the Owner for its costs of maintenance; obligation of the Owner to reimburse the County. If the County performs any maintenance work on the Facilities under Section 6, it will charge to the Owner all of the County's costs including, but not limited to, those costs for labor, equipment, supplies, materials, and project or contract administration. The Owner shall reimburse the County for its costs, subject to the following: Version: 01/17/17 A. Written demand. The County shall send to the Owner a written demand for payment of all of its costs. The demand may be sent by first class mail to the address to which County real property tax bills are mailed or to another address provided by the Owner to the County. B. Timely payment The Owner shall reimburse the County for the costs identified in the County's written demand within thirty (30) days after the date of the written demand. C. Collection by County. The County may collect any amount not timely reimbursed by the Owner in any manner authorized by law and may place a lien against the Property in the amount of the non -reimbursed costs, plus interest at the rate authorized by law. 8. Obligation of the Owner to indemnify and hold harmless the County. The following shall apply to this Agreement: A. No County liability. This Agreement imposes no liability of any kind whatsoever on the County, including its agents, officers and employees. B. Obligation of the Owner to indemnify and hold harmless. The Owner shall indemnify and hold harmless the County, including its agents, officers and employees, for any and all damages, accidents, casualties, occurrences or claims which might arise or be asserted against the County, including its agents, officers and employees, resulting from the failure of the Facilities to perform their design function or to otherwise operate properly, any repairs, maintenance, construction, or any other acts performed by the County or the Owner, including their respective agents, officers and employees, related to the Facilities, regardless of how those acts were performed; or the Facilities' existence. C. Notice of and defense of actions. If a claim is asserted against the County, including its agents, officers and employees, based upon any of the indemnities in subsection (B), the County shall promptly notify the Owner of the claim. The Owner shall defend, at its expense, any lawsuit or other action arising therefrom. If, as a result of a claim, any judgment is allowed against the County, its agents, officers and employees, or any of them, the Owner shall pay all damages, costs, expenses and fees associated with the judgment. 9. References to County departments and officers; successors. Any reference in this Agreement to a County department or office includes its successor department or office as determined by the County. 10. Covenant running with the land. This Agreement shall be recorded by the County in the Clerk's Office of the Circuit Court of Albemarle County, Virginia, shall constitute a covenant running with the land, and shall be binding on the Owner, its administrators, executors, assigns, 6 Version: 01/17/17 heirs and any other successors in interests, including any homeowners' association. 11. Date of this Agreement. This Agreement shall be deemed to have been entered into by the parties and shall be effective on and after the date it is signed by the Albemarle County Executive. WITNESS the following signatures: NAME R : ul STATE OF CITY/COUNTY OF The foregoing instrument was acknowledged before me this _ day of DATE by NAME My Commission Expires: Registration Number: Notary Public COUNTY OF ALBEMARLE, VIRGINIA 7 Version: 01/17/17 IN Thomas C. Foley County Executive COMMONWEALTH OF VIRGINIA CITY/COUNTY OF The foregoing instrument was acknowledged before me this _ day of by Thomas C. Foley, County Executive, on behalf of the Board of Supervisors of Albemarle County, Virginia. Notary Public My Commission Expires: Registration Number: Approved as to Form: County Attorney Date Version: 01/17/17