Title
Approval of a Resolution Authorizing a Professional Services Agreement for the Bioretention Hydraulic Performance Study with Associated Earth Sciences, Inc.
Recommended Action
Committee Recommendation:
Not referred to a committee.
City Manager Recommendation:
Move to approve a Resolution authorizing a Professional Services Agreement for the Bioretention Hydraulic Performance Study with Associated Earth Sciences, Inc. (AESI)
Report
Issue:
Whether to approve a Resolution authorizing a Professional Services Agreement for Phase III of the Bioretention Hydraulic Performance Study with AESI.
Staff Contact:
Eric Christensen, Water Resources Director, Public Works, 360.570.3741
Presenter(s):
None - Consent Calendar Item.
Background and Analysis:
Water Resources has agreed to sponsor a team of consultants led by Associated Earth Sciences, Inc. (AESI) to conduct the third phase of a Bioretention Hydraulic Performance Study (BHPS), a controlled field study of bioretention facilities (engineered rain gardens). The objectives of this study are to:
* Assess bioretention lifespans and address practical questions about how quickly different sites age through facility infiltration rates, soil composition, vegetation and maintenance practices.
* Conduct a point-in-time checkup on up to 50 older (10 years or older) bioretention facilities.
* Communicate the long-range bioretention effectiveness to a broad base of Statewide jurisdictions.
* Gather a large dataset on different systems to understand the possible influence of the above factors on performance.
* Provide guidance from an engineering perspective on what lessons we can learn studying these older sites; what are the critical factors to prevent bioretention site performance failure in future designs; and build confidence in the longevity of properly designed/constructed bioretention systems.
Funding for the implementing consultant team is provided through an agreement from the Washington State Departme...
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