Research Needs That Address Transportation Water Quality

G. Kenneth Young, Ph.D., P.E., Principal, GKY and Associates, Inc.
Stuart M. Stein, P.E., President, GKY and Associates, Inc.
Marjorie Zeffre

This needs synthesis derives from NCHRP project 25-20 which is one of several addressing impact analysis in the context of surface water resources. Related projects are 25-09, Impact of Construction and Repair Material on Surface and Groundwaters, 25-12, Wet Detention Pond Design for Highway Pollution Control, and 25-13, Assessment of Impacts of Bridge Risk Runoff Contaminants on Receiving Waters.

A number of research need statements on management of runoff have recently appeared, and collectively they have perplexed and confounded rational choice of which problem merits attention first, and of what should be done next - in short, how do you prioritize the diverse interests of states and TRB committee recommendations? The interests and recommendations overlap with regional differences coming to play to generate slightly different versions of the same need. What sets this research project apart from previous information syntheses on the subject is the objective of identifying and prioritizing research needs with an anticipation of future needs.

This project found knowledge gaps and suggested a research program to fill these gaps that is sensitive to the transportation context. The work identified needs for indicators and toxicity methods as transportation specific ways to resolve receiving water assessments. Other research is needed to isolate unambiguous transportation caused effects and to address the intervention of metal constituents that are very specific to highway runoff. In addition, research on space constrained BMPs is needed through projects to set criteria, find retrofitting methods, and provide demonstrations.