SW4230101_SNAP Version 4.2.0_20230615

Nutrient Export Summary
Landcover tt SCM Data Review
Errors/Advisories
Avg Annual precip (in) = 44.68
Total (Regulated+
Unregulated)Area (ft)_ 1,315,512
Project (Regulated)
_Area ( 1,315,512
ftZ)
Net BUA(Project Area
BUA only ftZ) 14,290 Net BUA indicates new development or expansion.
_
Custom Landcovers are
present:
no
Total Nitrogen Export Target
114.76
Scaled to Project Area (lb/yr):
Total Area Project Area Total Area Project Area
(Onsite+ Post-Project Post-Project
Nutrient Export Summary[ (onsite Only)
Offsite) Pre-Project before before
Pre-Project Treatment Treatment
Area (All Landcover Types)(acres) 30.2000 30.2000 30.2000 _ 30.2000
Percent Built-Upon Area(BUA) (%) 18% 18% 19% 19%
Built-Upon Area (BUA)(sgft) 237,196 237,196 251,486 251,486
Annual Runoff Volume(ft3/yr) 935,773 935,773 978,871 978,871
Annual Runoff%Change 5% 5%
Total Runoff Change(cuft/yr) 43,097 43,097
Total Nitrogen EMC(mg/L) 1.56 1.56 1.55 1.55
Total Nitrogen Load Leaving Site(lb/yr) 91.22 91.22 94.89 94.89
Total Nitrogen Loading Rate(Ib/ac/yr) 3.02 3.02 3.14 3.14 _
Total Nitrogen%Change Pre-to-Post 4% 4%
Total Nitrogen Change(lb/yr)Pre-to-Post \ 3.66 3.66
Total Phosphorus EMC(mg/L) 0.33 0.33 0.32 0.32
Total Phosphorus Load Leaving Site(lb/yr) 19.48 19.48 19.83 19.83
Total Phosphorus Loading Rate(Ib/ac/yr) 0.64 0.64 0.66 0.66
Total Phosphorus%Change Pre-to-Post 2% _ 2%
Total Phosphorus Change (lb/yr)Pre-to-Post LM L 0.35 0.35
L
SCM/Catchment Summary

SCM ID and Type Volume TN Reduction TP Reduction TN Out I TP Out
Reduction(%) N M (lbs/ac/yr) (Ibs/ac/yr)
Catchment 1 0.00% 0.00% 0.00% 0.00 0.00
101:NA 0.00% 0.00% 0.00% 0.00 0.00
102:NA 0.00% 0.00% 0.00% 0.00 0.00
103:NA 0.00% 0.00% 0.00% 0.00 0.00
Catchment 2 0.00% 0.00% 0.00% 0.00 0.00
201:NA 0.00% 0.00% 0.00% 0.00 0.00
202:NA 0.00% 0.00% 0.00% 0.00 0.00
203:NA 0.00% 0.00% 0.00% 0.00 0.00
Catchment 3 0.00% 0.00% 0.00% 0.00 0.00
301:NA 0.00% 0.00% 0.00% 0.00 0.00
302:NA 0.00% 0.00% 0.00% 0.00 0.00
303:NA 0.00% 0.00% 0.00% 0.00 0.00
Catchment 4 0.00% 0.00% 0.00% 0.00 0.00
401:NA 0.00% 0.00% 0.00% 0.00 0.00
402:NA 0.00% 0.00% 0.00% 0.00 0.00
403:NA 0.00% 0.00% 0.00% 0.00 0.00
Catchment 5 0.00% 0.00% 0.00% 0.00 0.00
501:NA 0.00% 0.00% 0.00% 0.00 0.00
502:NA 0.00% 0.00% 0.00% 0.00 0.00
503:NA 0.00% 0.00% 0.00% 0.00 0.00
Catchment 6 0.00% 0.00% 0.00% 0.00 0.00
601:NA 0.00% 0.00% 0.00% 0.00 0.00
602:NA 0.00% 0.00% 0.00% 0.00 0.00
603:NA 0.00% 0.00% 0.00% 0.00 0.00

SNAP v4.2.0
Errors/Advisories
SCM Area (ft2) = 0
SCM Treated Area (ft) = 0
Catchment Routing: No errors
Treating Runoff from
Existing BUA or Offsite: no
Disturbed Area (ft2) = 202,118
Total Phosphorus Export Target
43.19
Scaled to Project Area (lb/yr):
Total Area Project Area Total Area Project Area Total Area Project Area
Post-Project Post-Project Post-Project Post-Project Post-Project Post-Project
after Treatment after Treatment SCM-Treated SCM-Treated Untreated Untreated
Area Only Area Only Areas Areas
30.2000 30.2000 0.0000 0.0000 30.2000 _ 30.2000
19% 19% 0% 0% 19% _ 19%
251,486 251,486 0 0 251,486 _ 251,486
978,871 978,871 0 0 978,871 978,871
43,097 43,097
1.55 1.55 0.00 0.00 1.55 1.55
94.89 94.89 0.00 0.00 94.89 _ 94.89
3.14 3.14 0.00 0.00 3.14 3.14
3.66 3.66
0.32 0.32 0.00 0.00 0.32 0.32
19.83 19.83 0.00 0.00 19.83 19.83
0.66 0.66 0.00 0.00 0.66 0.66
2% z%
0.35 0.35

Falls Lake ONLY: Onsite Reduction Compliance Check
Nitrogen Phosphorus
Onsite%Reduction Requirement
Export Target Scaled to Area(lb/yr) 114.76 43.19
Export Load Post-Project Before Treatment 94.89 19.83
Total Reduction Need (lb/yr)
Onsite Reduction Need (lb/yr)
Onsite Export Target(lb/yr)
Project Area Post-Project After Treatment 94.89 19.83