Arroyo Seco Watershed Restoration

Stillwater Sciences brings an in-house, aquatic, geomorphic, hydrologic, and restoration engineering team of experts who are passionate about native fish restoration. We are currently working on native fish habitat planning, barrier removal, fish population monitoring, watershed environmental flow analyses, design, CEQA/NEPA/ permitting, and/or construction projects in the Arroyo Seco, Trabuco and San Juan Creeks, Los Angeles River, San Gabriel River, Santa Clara River, and Ventura River Watersheds.

Stillwater recently completed Native Fish Habitat Monitoring of the Central Arroyo Seco stream restoration, post-Station Fire, for a Design-Build project that Wendy Katagi, C.E.P. (Senior Manager, Watershed and Ecosystem Restoration Services) managed prior to joining Stillwater. The intent of the stream restoration enhancements are to create improved habitat conditions for sustaining the native Arroyo Chub (Gila orcutti), a California Species of Concern. The improvements provide refuge, resting areas and spawning areas which included two backwater pools in the south project area provide resting areas during high flow events. Three weirs were constructed to direct flow to the appropriate part of the channel as needed during low flow conditions to maintain water levels in the backwater pools. A total of 0.3 acres of stream habitat area was restored.

This project won multiple awards including the Governor’s Outstanding Environmental Project Award. Stillwater Sciences completed post-construction monitoring of native fish habitat in the Central Arroyo as well as recommendations for native fish recovery for the Arroyo Seco Foundation. Excellent habitat exists for rainbow trout, arroyo chub, and other native fishes.


Location: Arroyo Seco Watershed, Southern California

Clients: Arroyo Seco Foundation and City of Pasadena

Project Manager: Wendy Katagi

Project Lead(s)

Wendy Katagi
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Work Products

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AJ Keith, Stillwater Sciences Senior Aquatic Ecologist, surveying Central Arroyo Seco stream restoration habitat conditions, post-Station Fire.

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