TPDES Stormwater Annual Report FY2021 TPDES Stormwater Annual Report FY2021 | Page 52

Education & Outreach
7.0
Ongoing Stormwater Education Participation and inclusion of bacteria-specific materials
forum by attending a minimum of 1 meeting per year .
Include one explainer video related to TMDLs on the City ’ s website .
Stormwater Quality Manager attended 3 out of three meetings . One TMDL explainer video was incorporated on the City ’ s Stormwater webpage in FY21 .
Identify by the end of FY21 , a minimum of one ( 1 ) benchmark for each POC : The permit requires that benchmarks be determined for POCs identified by permittees . The primary POC for the City of Arlington is bacteria . The benchmark must be determined by either of the two methodologies ( A or B ) outlined in the City of Arlington ’ s MS4 permit .
The City chose to utilize the methodology outlined in Option A : waste load allocations for permitted MS4 stormwater sources . Waste Load Allocations ( WLAs ) for regulated stormwater sources for TMDL and impaired waters are calculated and outlined in the I-plan . WLAs for impaired assessment units ( AUs ) within Arlington ’ s jurisdiction are listed below . These WLAs will serve as the benchmarks for TMDL and impaired waters within Arlington . All loads are expressed as billion MPN / day .
Assessment Unit ( AU )
Stream Name
WLASW
0841 _ 02
Lower West Fork Trinity River
1920.0
0841F
Cottonwood Creek
46.053
0841K
Fish Creek
103.393
0841L
Johnson Creek
491.0
0841M
Kee Branch
184.4
0841R
Rush Creek
678.7
0841T
Village Creek
357.9
Continue to implement the Year 1 goal – monitoring bacteria levels monthly at 13 established locations throughout the MS4 ’ s watersheds : See Year 1 Goal outlined above .
By the end of FY21 , review all SSO discharges that reached a waterbody occurring from 2010-2019 to determine MS4 contribution : Based on the available data , the City has determined that it may be a source of the pollutant of concern identified in the SWMP and the CWA 303d list and that discharges from the MS4 would likely contain the POC above the LOC . Between 2010 and 2020 a total of 618 SSO ’ s have entered a waterbody or drainage course with a total of over 9 million gallons of sewage discharged .
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