A preliminary study of runoff of selected contaminants from rural Maine highways

Abstract 1Introduction 1Site Descriptions 2Data Collection 3Physical Characteristics of Highway Runoff 4Chemical Characteristics of Highway Runoff 6Total Phosphorus and Biologically Available Phosphorus 7Sediment Fractionation 8Load Computations 10Annual Export Estimates of Phosphorus and Total Sediment. 14Limitations of the Study 15Summary 16References 18FIGURES1. Map showing location of the highway runoff study sites in west-central Maine........ 22. Illustration of the highway runoff collection and sampling scheme for theRoute 27 site in Rome, Maine. 33. Graph showing the relation between total phosphorus concentration and sediment weight in highway stormwater runoff samples 74. Graph showing the regression function for estimating total phosphorus load, as a function of peak discharge, for unsampled runoff at the Kimball Pond Road site, New Sharon, Maine 115. Graph showing paired phosphorus digestion data for 1995, illustrating the extrapolated function used for estimating biologically-available phosphorus from total phosphorus record. Kimball Pond Road site, New Sharon, Maine 14TABLES1. Precipitation and snowfall data for New Sharon, Maine. 42. Summary of total sediment, specific conductance, and pH data, by site. 63. Summary of phosphorus concentration data, by site. 64-6. Fractionation and phosphorus concentrations for a sediment sample collected May 20, 1993 from:4. The ditch of Kimball Pond Road runoff site New Sharon, Maine 85. The shoulder of Route 27 runoff site, Rome, Maine 96. The sanding pile at the Maine Department of Transportation lot,Mercer, Maine 97. Number of events and total runoff sampled, by site, during study 108. Standard error of estimate for load estimating regression models by siteand constituent. 119. Total and biologically-available phosphorus data for sediment samples taken from the highway runoff sites and Maine Department of Transportation sanding piles 1210. Export estimates for dissolved orthophosphate, total phosphorus,biologically-available phosphorus, and total sediment at three highway sites in west-central Maine, September 1992 through August 1993 15