Looking All Over for Urban Storm Water BMP Opportunities — An Island-Wide Storm Water Retrofit, Oahu, Hawaii

As a proactive effort and as part of its NPDES MS4 program, Hawaii Department of Transportation, Highways Division (HDOT-HWYS) is conducting an Island-wide feasibility study for retrofitting its existing MS4 system on the Island of Oahu that discharges to the receiving waters listed on the Section 303(d) of the Clean Water Act. The targeted pollutants include sediment, siltation, turbidity, and/or trash. The retrofits are to include both source-control and stream-based control as well as maintenance related best management practices (BMPs) designed to improve water quality of the receiving streams, bays and ocean. Major objectives of the study include: 1 Identify and evaluate potential pollutant sources from HDOT MS4 that may cause storm water pollution and stream degradation; 2 Identify management measures related to HDOT Highways activities for the pollutant reduction and reestablishment of stream stability; 3 Identify potential opportunities for installing permanent BMPs controls within HDOT right-of-way; 4 Rank and prioritize management and control BMPs identified in the study.