Between South Pasadena and Highland Park is a tiny wilderness of Mexican fan palms and even some oak trees. Some locals say they love it the way it is, graffiti, fire hazard and all.
But the city of Pasadena says it needs the place to filter out E. coli bacteria and zinc pollution that ruin water quality in the Arroyo Seco, which then flows into the L.A. River.
The Arroyo Seco is born in the Angeles National Forest and winds through through La Cañada Flintridge, Altadena, Pasadena and South Pasadena and finally Los Angeles. The water-cleaning project has been drawing protests from several community groups and some elected representatives for the area. Neighbors have organized a lawsuit against the city and there’s a growing social media campaign to bring the project to a halt.
Pasadena plans to remove some of the densely clustered trees in the two-acre wood next to San Pascual Park to make way for a new wetland ringed by native plants and walking paths.
The city would remove thousands of cubic yards of soil and plants — six dump trucks’ worth each day — over about five months. It would make infiltration basins and widen the stream’s path over them to maximize water filtered by the soil as it slows and is drawn by gravity underground to recharge the aquifer.
In 2010, a resolution by the Los Angeles Regional Water Quality Control Board set maximum bacteria levels allowed in the watershed. In response, Pasadena and South Pasadena secured close to $15 million for the water reuse project. Pasadena has said it faces fines of up to $10,000 a day from the board for not reducing bacteria, but those haven’t been imposed yet.
At first glance, it might seem like a lot of commotion over a parcel that is about the size of two football fields. But to community members, unpaved and unmanicured areas such as the verdant tangle of vegetation in the San Pascual site are an invaluable part of the city’s limited green space.
“They’re going to go in and bulldoze that whole thing, wipe it all out, and then they’re going to put in these pools that will store water, and then they’ll put some vegetation around the side of it,” said Tim Brick, executive director of the group Stewards of the Arroyo Seco. He described the site as a “little environmental gem.”
Andrew Salas, chair of the Gabrieleño Band of Mission Indians — Kizh Nation, called for a “full avoidance” of the area. In a letter to city officials, he wrote that the project risks permanently damaging fragile and tribal sites within the Hahamongna Watershed, and includes a “high probability of encountering ancestral human remains.”
The place is used.
“People will go down there and sit, because it’s like 10 to 15 degrees cooler there by the stream,” said Clara Solis, a member of Save San Pascual Park. People nearby don’t all have air conditioning, she said. “It’s valuable to us.”
She said her appreciation of trees comes from growing up in unincorporated East L.A., near the 60 and 710 freeways. She saw trees in her neighborhood cut down to make it easier for cars to exit the freeway, resulting in more freeway noise and pollution. The trees had been a shield.
When Solis learned that close to 140 trees were to be removed in the Arroyo Seco project, she jumped into action.
She led a lawsuit against Pasadena in 2024, alleging it didn’t carefully consider the effect the project would have, prompting the city to do a full environmental impact report.
Grassroots organizers also say the first wave of notices did not reach many residents who live on one side of the arroyo and were distributed only in English.
Though the objections to the project are diverse and heated, what unites almost everyone is the desire for a cleaner Arroyo Seco.
The environmental nonprofit Heal the Bay gave it an F on its Annual River Report Card in 2025, mainly for E. coli.
Brent Maue, city engineer for the Public Works Department of Pasadena, said the San Pascual site is a good candidate for this work. The sliver of land is “one of the few” where it’s possible to improve water quality and restore a wetland at the same time, he said in an email. More people will be able to use it, too.
Christina Monde, Pasadena’s city project manager for the Arroyo Seco project, attributed some of the opposition to misconceptions, such as that Pasadena is cleaning the water in order to irrigate a golf course. But the pipe that takes water for that golf course dates back 70 years and its capacity will not increase, she said. The draft environmental impact report supports that.
Monde doesn’t think the wild patch is so important to keep in its current state.
“It’s just not the pristine area that people say it is, and I think that the improvements that we’re proposing will make it a much more aesthetically pleasing, accessible, and safe area for the community to enjoy,” she said, citing unauthorized trails, overgrowth, unhoused people living there, broken chain-link fencing as well as barbed wire and algae.
She noted that 82 of the 136 trees to be removed are invasive Mexican fan palms, which also pose a fire hazard.
The public comment period on the draft environmental report has been extended to Saturday. Comments should be sent to [email protected]. There will be another community meeting, Monde said, but no date has yet been set.
Visiting the San Pascual site today illuminates all sides of the debate. A rusted fence almost entirely encircles the lot. There is a path in from the northern corner, marked by a hand-painted wooden sign on a utility pole that reads “HANDS OFF THIS.” Following the path feels like a peek into a Jurassic jungle as it unspools past lush clusters of palms, coming close to a small stream diverted from the Arroyo, and all the bacteria it carries.