2.4 SPRCTAL PRORI.EMS TN MANAGEMENT OF RUNOFF 

 LAWN CARE-RELATED CONTAMINANTS 



Findings and Concerns 



Pesticide and fertilizer application on hotne lawns has increased steadily since the 

 beginning of the 1970's, and chemicals are frequendy applied adjacent to impervious zones 

 having high potential for surface nmoff. The Long Island NURP study monitoring results 

 indicate that medium density residential development has the highest loading factor of any 

 land use studied (Long Island Regional Planning Board, 1982). Other researchers have 

 identified turfgrass, in particular, as a source of substantial levels of contaminant leachate. 



A 1980 survey conducted by Cornell University showed that 39 percent of the 

 residential land on Long Island was in turfgrass (130,000 acres) and that an additional 

 26,000 acres of turf was associated with commercial development The study found a 

 direct correlation between fertilizer use and affluence, with wealthier communities heavily 

 utilizing lawn care services (Cornell Water Resources Inst, 1985). 



The Long Island study assembled a range of statistical data on application. In the most 

 affluent communities, 98 percent of residents used fertilizers on their lawns and gardens, 

 72 percent used lawn care services, and the average fertilizer application rate was 3.3 

 pounds per 1000 square feet of turf. In the least affluent neighborhoods, 45 percent of 

 residents used fertilizer and none subscribed to lawn care services. In those areas, the 

 average fertilizer application rate was 1.1 pounds per 1000 square feet Overall, the 

 average for Long Island turfed areas was 2.3 pounds per lOCX) square feet, or between 

 6500 and 8500 tons of fertilizer applied annually. On mature lawns, any amount over 1 

 pound per 1000 square feet is excessive, and is likely to reach receiving waters via runoff 

 or leaching into groundwater (Cornell Water Resources Inst, 1985). 



Attiibutirai of residential loadings depends upon the extent of sewering and the 

 condition of ISDS. In sewered areas, where the primary source of nitrates is turf and 

 garden care practice, the 1980 Long Island study showed that nitrate levels were correlated 

 with housing density, such that levels ranged between 3.0 to 4.3 ppm at one house per 

 acre, and up to 1 1 to 15.5 ppm. at densities of five to ten houses per acre. The authors 

 concluded that though affluent neighborhoods fertilize more readily, smaller house lots 

 have higher proportions of land in turf (Cornell Water Resources Inst, 1985). 



The Planning Board of the Town of Falmouth cited other studies of the use of fertilizer 

 on lawns which showed a range of averages from 1,52 lbs. N per 1000 square ft. 

 (standard deviation 1.4) to 3.75 lbs N per 1000 square ft Socioeconomic and environ- 

 mental factors identified as playing a large pan in the size and fertilization of lawns included 

 average income of residents; age of the development; zoning status; maturity of lawns; size 

 and age of trees in the area; topography of land area (Memorandum to the Falmouth, 

 Massachusetts Planiung Board from K. Buckland, Town Planner, Nov. 25, 1986). 



Golf courses, cemeteries, and other heavily landscaped areas have also been sources of 

 concern with regard to contaminant loading. On Long Island, in the same study, 

 researchers found that more fertilizer (4.3 pounds/1000 square feet) is used on golf course 

 greens than on fairways (3.1 pounds/1000 square feet). However, fairways constitute 74 

 percent of the course area, and clippings are left to serve as mulch, so nitrate levels are 



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