1240815StormWaterManagementReportrcd 3 12 2026

Project Name Description Analysis Date BMP or LID Type 1240815 Pleasant Valley Way, W Orange 12/04/25 Recharge BMP Input Parameters Root Zone Water capacity Calculated Parameters Recharge Design Parameters Parameter Symbol Value Unit Parameter Symbol Value Unit Parameter Symbol Value Unit Empty Portion Inches of Runoff BMP Area ABMP 160.0 sq.ft of RWC under Post-D ERWC 0.61 in Qdesign 0.05 in to capture Natural Recharge BMP Effective Depth, ERWC Modified to Inches of Rainfall dBMP 0.2 in EDRWC 0.18 in Pdesign 0.10 in this is the design variable consider dEXC to capture Upper level of the BMP Empty Portion surface (negative if above Recharge Provided dBMPu 1.0 in of RWC under Infilt. RERWC 0.14 in

d dBMPu 1.0 in of RWC under Infilt. RERWC 0.14 in 0.1 in ground) Avg. over Imp. Area BMP Depth of lower surface of Runoff Captured dEXC 40.8 in 0.3 in BMP, must be>=dBMPu Avg. over imp. Area Post-development Land Segment Location of BMP , SegBMP 1 unitless Input Zero if Location is distributed or undetermined BMP Calculated Size Parameters CALCULATION CHECK MESSAGES ABMP/Aimp Aratio 0.01 unitless Volume Balance-> OK BMP Volume VBMP 3 cu.ft dBMP Check---> OK Parameters from Annual Recharge Worksheet System Performance Calculated Parameters dEXC Check---> OK Post-D Deficit Recharge Annual BMP Recharge (or desired recharge Vdef 109 cu.ft 109 cu.ft Volume volume) BMP Location---> OK

Volume volume) BMP Location---> OK Represents Post-D Impervious Area Avg BMP Recharge Aimp 11,238 sq.ft 41.6% % Infiltration (or target Impervious Area) Efficiency Recharged OTHER NOTES %Rainfall Root Zone Water Capacity RWC 3.69 in 78.5% became Runoff % Pdesign is accurate only after BMP dimensions are updated to make rech volume= deficit volume. The portion RWC Modified to %Runoff DRWC 1.12 in 0.7% consider dEXC Infiltrated % of BMP infiltration prior to filling and the area occupied by BMP are ignored in these calculations. Results are %Runoff Climatic Factor C-factor 1.67 no units 0.3% Recharged % sensetive to dBMP, make sure dBMP selected is small enough for BMP to empty in less than 3 days. For land %Rainfall Average Annual P Pavg 49.0

ough for BMP to empty in less than 3 days. For land %Rainfall Average Annual P Pavg 49.0 in 0.2% Recharged % Segment Location of BMP if you select "impervious areas" RWC will be minimal but not zero as determined by Recharge Requirement dr 0.1 in over Imp. Area the soil type and a shallow root zone for this Land Cover allowing consideration of lateral flow and other losses. How to solve for different recharge volumes: By default the spreadsheet assigns the values of total deficit recharge volume "Vdef" and total proposed impervious area "Aimp" from the "Annual Recharge" sheet to "Vdef" and "Aimp" on this page. This allows solution for a single BMP to handle the entire recharge requirement assuming the runoff from entire impervious area is available to the BMP. To solve for a smaller BMP or a LID-IMP to recharge only part of the recharge requirement, set Vdef to your target value and Aimp to impervious area directly connected to your infiltration facility and then solve for ABMP or dBMP. To go back to the default configuration clik the "Default Vdef & Aimp" button. 144