SUSTAIN Application for the Optimization of Stormwater BMPs to Improve Biological Conditions in an Urban Stream in Southern British Columbia.

Optimization of stormwater BMP siting and dimensions was achieved through the application of SUSTAIN, a decision support system available from the US EPA (Environmental Protection Agency). Interpretation of the B-IBI scores (Benthic Index of Biological Integrity) assessed the creek benthic invertebrates to be in “poor” biological condition. Management objectives included control of stormwater runoff discharges to reduce the flashiness of the hydrological response and to control pollutant emissions. BMPs were optimized through a multi-objective optimization geared towards obtaining a cost-effective suite of alternatives in order to achieve the best level of control for improving biological in-stream conditions.