Phosphorous Loading in the Blackstone Watershed Where does it come from And What can we do about it? Blackstone River User’s Conference September 18, 2012 Peter Coffin, Coordinator, Blackstone River Coalition
MAMADEPCWMHSPF LU CodeDescription PPP 3Forest Res MultiMulti-family Residential Res High Den High Density Residential (< 0.25 acre lots) Res Low Den Low Density Residential (> 0.5 acre lots) CommercialGeneral Urban, Shopping Center Urban Open Parks, Cemeteries, Undeveloped Open Land Transport Airports, Docks, Divided Highways, Freight, Railroads Regional and model export coefficient comparison for phosphorus in lbs/acre/year
Land Use Code*Land UsePerviousImpervious 1Cropland Pasture Forest Non-Forested Wetland00 5Mining Open Land Participation Recreation Spectator Recreation Water-Based Recreation00 10Multi-Family Residential High Density Residential Medium Density Residential Low Density Residential Saltwater Wetland00 15Commercial Industrial Transitional Transportation Waste Disposal Water00 23Cranberry bog00 24Powerline/Utility Saltwater Sandy Beach00 26Golf Course Marina00 31Urban Public/Institutional Cemetery Orchard Nursery Forested Wetland00 38Very Low Density Residential Junkyard Brushland/Successional Phosphorus Load (lb./ac/year) in Blackstone River Watershed from HSPF Model
Overlay Phosporous Load Map on to Google Earth 30 meter pixels highlight Phosphorous Loads
Bioretention and rain gardens use plant and microbes in the practices to treat pollutant loads. These can range in removal efficiency of 30% to 90% (MA DEP).
Water Quality Swale (Image Source: Portland Bureau of Environmental Services) These are vegetated open channels to treat 10-year storms (MADEP). Pollutant removal efficiency is 20% to 90% for phosphorus.