1. Presented to: Severn River Association 2008 State of the Severn Anne Arundel County Government Department of Public Works Ron Bowen, P.E. October 21, 2008

2. Anne Arundel County Impervious Areas Our “greatest challenge” is restoration of those areas developed in an era when storm water management was non-existent or much less than it is today... Historical Urbanization vs. New Development

3. Severn River Watershed Impervious Cover Landcover Acres Impervious Acres Impervious % of Landcover % of Total Impervious Commercial (Private Lands) 1,9711,505 76 %16 % Industrial (Private Lands) 50638175 %4 % Residential (Private Lands) 16,3324,00124 %43 % Gov’t Owned (Public Lands) 10,2192,95629 %32 % Other (Private Lands) 15,3254473 %5 % Total44,3539,29021 %100 %

4. EPA/MDE Clean Water Act Listed Impaired Waters Severn River Pollutant Impairments Bacteria – Fecal Coliform for Shellfish Harvesting TMDL issued Biological (combination Benthic/Fish) Nutrients (Total Nitrogen and Total Phosphorous) Sediments Toxics (PCB in Fish Tissue)

5. Severn River Watershed Total Nutrient Loads from Stormwater and Septics Total Nitrogen (TN) TN (lbs/yr) - Existing TN (lbs/yr) - Buildout % Increase Total Phosphorous (TP) TP (lbs/yr) - Existing TP (lbs/yr) - Buildout % Increase = 449,629 = 490,257 = 9 % = 25,594 = 27,117 = 6 %

6. Severn River Watershed Existing Septic Systems Annual Nitrogen Load Critical Area104,975 lbs/year Non-Tidal Surface Streams112,342 lbs/year All Remaining Areas22,032 lbs/year Total239,349 lbs/year

7. Septic Systems within the Severn River Recommended Retrofits

8. Best Overall Conditions Worst Overall Conditions City of Annapolis Severn River Watershed Subwatershed Condition Assessment for Restoration

9. Severn River Watershed Stream Restoration Challenge 178 miles of total non-tidal streams 25 miles are degraded streams Rated poor to very poor Degraded Streams Stream Reaches

10. Severn River Watershed Stormwater Controls Watershed Area Acres Percent % 44,213 -- Managed Area 6,370 14 Managed Public Area Managed Private Area 3,86460 2,506 40 Note: Only 19% of current Stormwater controls provide water quality treatment Management Areas have varying degrees of impervious contribution (Avg 21%)