Challenge

Clean Water Services (CLS) needed assistance in carrying out a long-term water resources plan to improve watershed health, enhance streamflows, restore aquatic habitats, and identify actions to manage a large water rights portfolio within the Tualatin Basin.

Solutions

Clean Water Services contracted Summit to support an assessment of innovative tools to potentially add to CWS’ water quality credit trading program for temperature. Our team began by supporting a feasibility assessment of using aquifer storage and recovery (ASR) as a water management tool to mitigate thermal impacts from the District’s water resource recovery facilities. Our team gathered information for the report by first assessing the availability of source water for subsurface storage, characterizing the local hydrogeologic setting, assessing permitting feasibility, estimating the quantity and quality of stored water during recovery, characterizing potential impacts to existing water users and environmental conditions, and estimating potential benefits including generation of thermal credits.

CWS also retained Summit to assist with wider water rights management as a result of our assistance with the long-term water resources planning, specifically to support with management of the District’s water right portfolio. we’ve assisted CWS to identify strategies to manage and secure a large water rights portfolio within the Tualatin Basin. Further, Summit is currently providing support with an ongoing investigation of potential sources, extent, and fate and transport of per- and polyfluoroalkyl substances (PFAS) in shallow groundwater across the Tualatin Basin.

Results

Based on the feasibility evaluations, our team was able to develop planning level capital and O&M costs for the ASR offset. We have produced an innovative approach of using ASR as a water management tool by storing cold (<10°C) water in the subsurface during the winter and then recovering stored water during the summer for streamflow enhancement of 303(d) impaired waterbodies and aquatic habitat restoration.

Our team strives for the most innovative approaches for our clients.”