APPLICATION OF A GIS-BASED NONPOINT-SOURCE NUTRIENT LOADING MODEL FORASSESSMENT OF LAND-DEVELOPMENT SCENARIOS AND WATER-QUALITY IN OWASCO LAKE, NEW-YORK
Tm. Heidtke et Mt. Auer, APPLICATION OF A GIS-BASED NONPOINT-SOURCE NUTRIENT LOADING MODEL FORASSESSMENT OF LAND-DEVELOPMENT SCENARIOS AND WATER-QUALITY IN OWASCO LAKE, NEW-YORK, Water science and technology, 28(3-5), 1993, pp. 595-604
Citations number
12
Categorie Soggetti
Water Resources","Environmental Sciences","Engineering, Civil
The magnitude and water quality implications of nonpoint source phosph
orus loadings to Owasco Lake (New York) are evaluated through the appl
ication of a methodology which links geographic characteristics, long-
term average runoff loads and a set of critical lakewide water quality
response parameters. The approach utilizes the Universal Soil Loss Eq
uation together with empirical loading functions to derive representat
ive phosphorus export coefficients for the local drainage system. Cumu
lative loadings from individual sub-basins within the watershed serve
as input to a simple water quality model of Owasco Lake, showing the e
xpected lake response in terms of average total phosphorus concentrati
ons, trophic state, water transparancy, and minimum hypolimnetic disso
lved oxygen concentration. The methodology facilitates easy and rapid
assessment of general watershed management and development scenarios o
f interest. A unique aspect of the approach is its dependence upon des
criptive data supplied by a Geographic Information System (GIS) to est
ablish the coincidence of specific land use, soil texture and surface
slope attributes within each of the hydrologic sub-basins comprising t
he overall watershed. The GIS-generated attribute matrices provide a m
uch more accurate depiction of critical geographic characteristics kno
wn to impact nonpoint source runoff loadings, thereby improving the re
liability of current and projected phosphorus loads to Owasco Lake.