Geomorphically-informed design at high speed
unexpected challenges
In early 2017, the Zone 7 Water Agency called FlowWest with a big problem. Heavy rains and flows in the Livermore Valley had blown out a stream bank on Arroyo De La Laguna on the outskirts of Pleasanton - a 40-foot high bank had retreated at least 40 feet and threatened homes.
Approaches that Deliver
We led a team that achieved what initially seemed impossible. Between March and October 2017 we designed, permitted, and constructed a ~$3.5 million project that stabilized the stream bank using virtually all natural materials, created new riparian habitats; and addressed geomorphic problems in the reach to ensure that the project would be sustainable in the long term. The cost of failure would have been high.
ecological Alternative
Conventional engineers would have stabilized this bank with inert materials that deteriorate with age. Our approach is ecologically based - it will get stronger as willows and other vegetation mature and it uplifts native habitats in the arroyo.
This rapid outcome required creativity, ability to interact with and manage expectations and emotions of landowners and stakeholders, credibility with regulators, and knowing how to work hand-in-hand with the contractor to get the project built quickly and properly.
