‘Trees of Heaven’ and Mexican Fan Palms are among the invasive species that dominate the proposed site area in Arroyo Park
The latest chapter in decades of work to re-naturalize the Arroyo Seco is well underway.
By Wesley Reutimann
A multi-jurisdictional effort touching the cities of Pasadena, South Pasadena, and Los Angeles, the ‘Arroyo Seco Water Reuse Project’ calls for new, nature-based water infrastructure on two sites in the lower Arroyo. The beloved open space and tributary to the Los Angeles River was largely converted to a concrete flood control channel in the 1930s and 1940s.
The first site adjacent to the terminus of San Rafael Creek would divert and clean water before it enters into the Arroyo Seco. Further downstream, a space next to Arroyo Park in South Pasadena would employ a similar approach to one implemented below the Colorado Street Bridge two decades ago. Once again water from the existing concrete channel would be diverted to new wetlands designed to remove pollutants via natural processes. Both sites would also rehabilitate and expand existing walking trails.
The space between Stoney Drive and the Arroyo Seco is one of two sites slated for green infrastructure investments (Photo – City of Pasadena)
Project goals include improving water quality in the existing channel, recreating riparian habitat, increasing trail access, and supporting biodiversity. The project also calls for the removal of highly invasive species – including Trees of Heaven, toxic Castor Bean plants, and Mexican Fan Palms – that have overtaken the Arroyo Park site (image below). In their place native trees will be planted, providing improved habitat to local insects, birds, and wildlife.
‘Trees of Heaven’ and Mexican Fan Palms are among the invasive species that dominate the proposed site area in Arroyo Park
The Arroyo Seco Water Reuse Project calls for new, nature-based water infrastructure on two sites in the lower Arroyo. In addition, the project is aimed at reducing use of drinking water for irrigation. Per project planning documents, 12% of the water treated in the new wetlands space will be redirected to the Arroyo Seco Golf Course. This approach should help reduce the region’s reliance on imported drinking water at a time when the primary sources of such water – the Colorado River and Sierra snowpack – is becoming less reliable.
Made possible with competitive funding from Los Angeles County Measure W and the state of California, the $8.2 million project is expected to be further refined in the coming months. After environmental permitting is completed, construction bidding is then expected to take place, with final construction slated for 2025. More information about the project can be found on the City of Pasadena’s website.
Leave a Reply