Pasadena Council Approves CUP and Mitigated Negative Declaration

June 1, 2015 - The Pasadena City Council certified the environmental document and approved a conditional use permit for the Arroyo Seco Canyon Project, a partnership between Pasadena Water & Power Department and the Arroyo Seco Foundation. The project will expand local water supplies from the Arroyo Seco stream and local groundwater while at the same time improving environmental conditions for fish and habitat. Enhancements to Pasadena's water intake structure in the mountain canyon will improve its reliability as well as conditions for fish and aquatic species. The spreading basins at the top of Hahamongna Watershed Park will be expanded to allow Pasadena to take its full entitlement during high flow periods by reducing the size of the former JPL parking lot on the east side of the basin from 1100 spaces to less than 100 reserved for recreational visitors. Arroyo Seco Foundation developed the original conceptual plan and grant application for this project and has worked closely with Pasadena Water & Power to publicize and shape the program. We are excited about the nursery that we are now developing to propagate native plants for the habitat restoration elements of the project. The project should be completed in two years.

View or download these key documents:
Mitigated Negative Declaration | Conditional Use Permit  |  Response to Comments

The Arroyo Seco Canyon Project (ASCP) is an innovative program to improve water resources, habitat, and recreational opportunities in the area between Hahamongna Watershed Park in Pasadena and the Angeles National Forest. Projects like this that contribute to long-term sustainability become all the more vital as our region faces severe drought conditions.

ASCP is a partnership between the Pasadena Water and Power Department and the Arroyo Seco Foundation (ASF) funded by the California Integrated Regional Water Management Program and Pasadena Water and Power Department. ASF provided the initial conceptual design and secured a $3.3 million grant from the State of California for the project.

Project benefits include:

  • Improving fish passage
  • Increasing local water supply
  • Enhancing water quality
  • Restoring aquatic and riparian habitat
  • Improving passive recreational opportunities

Project elements include:

  • Rehabilitation of the intake structure. The Arroyo Seco water intake structure diverts water from the Arroyo Seco stream for public use. The upgraded facility will better manage sediments and improve the ability to reliably supply clean fresh drinking water to Pasadena residents by replenishing the City's groundwater.
  • Installation of a public restroom. A restroom facility will be built next to the new parking area at the entry to the highly used Gabrielino Trail. This restroom will improve the water quality of the Arroyo Seco Stream by decreasing human bacteria in canyon water flows and will enhance the recreational experience in the canyon.
  • Removal of unused water facilities. The removal of the Headworks facility will allow for naturalization of the stream and improve aquatic connectivity. This outdated facility will no longer be necessary thanks to improvements at the intake and other facilities.
  • Habitat restoration. The former area of the Headworks facility will be restored with ecologically appropriate woodland, plant, and riverine habitat to encourage birds, insects, butterflies, fish, and frogs to thrive. Invasive species will be removed through clearing of non-native plants.
  • Improving passive recreational opportunities. Installation of interpretive signs, picnic tables, a drinking fountain, and a horse trough will enhance recreational use.

Click HERE to download the full conceptual design report released in 2013.