MODELING OF NONPOINT SOURCES IN TICKFAW RIVER WATERSHED

Abstract

Louisiana has twelve water quality management basins delineated by natural drainage patterns of the state's major river basins. The Tickfaw River watershed in the Lake Pontchartrain basin is especially challenged from rapid population growth, industrial activities, and agricultural use. This watershed is located in southeastern Louisiana with Tickfaw River flowing from the Mississippi state line to Springville at Louisiana Highway 42 then to Lake Maurepas with a total drainage area of 1,896 km2. The elevation of the watershed changes from 0 m above sea level in the south to 130 m in the north. Forests cover 66% of the watershed. Agriculture is the second predominant land use type in the watershed. Outstanding natural resource and secondary contact recreation designated uses are fully supported, but fish and wildlife propagation and primary contact recreation are not supported. There are many suspected sources of impairment, including agriculture, construction, forest management, and industrial sources. The specific objective is to model the Tickfaw river watershed in order to quantify and differentiate the sources of pollution that arise from agriculture, forestry, urban storm water runoff, and other sources making use of a Geographic Information System (GIS), the EPA’s BASINS tools, HSPF for modeling water quantity and quality, and ArcView 3.2.