The Brief

Restoration of the Arroyo Seco trail is set to break ground in July and construction will be in full swing starting in August.

The Arroyo Seco, often referred to as just “the Arroyo,” is a protected parkland in Pasadena that contains the Arroyo Seco stream and canyon that stretches 8 miles through the western part of the city. The area contains 22 miles of trails throughout.

The Restoration

The project will focus on two critical linkage points for the three major areas of the Arroyo: the Hahamongna Natural Park, the Central Arroyo, and the Lower Arroyo.

“Both of those areas are fairly natural and have suffered greatly over the years,” said Rick Gould, managing director of the One Arroyo Foundation, the nonprofit in charge of improving the Arroyo. “It's hard to get to, quite frankly, and so the trails have deteriorated.”

Restoration of the trail will include fixing erosion issues, rebuilding some of the rock walls that have collapsed, and adding new connections to the other trails, Gould said.

“There are some slopes that have either been landslides that need to be rectified or the slope is so heavily eroded it looks more like a pile of rocks than it does a trail,” Gould said.

The design stage for the trail’s restoration started back in 2020. But due to COVID-19, One Arroyo had to extend their initial timeline for the project, spending the next two years fine-tuning the improvement plans.

The city will decide on a contractor for the project in the next 10 days or so, said Daniel Rothenberg, president of One Arroyo, with the groundbreaking ceremony slated for July.

The project will then hopefully be completed within four months, prior to the rainy season, sometime in mid-November or early December.

During the renovation, hikers can expect to see some construction work along the way. Small sections of the trail may be closed for a few days at a time, but the majority of the trail should remain open, Gould said.

Other aspects of the project include improving the Mayberry Parker Bridge that lays underneath the Colorado Street Bridge. That renovation will enable people to more easily access other parts of the Arroyo.

“It hopefully will promote usage of the trails and more activity down there,” Rothenberg said.

Gould also emphasized the project’s goal to help unify the Arroyo.

“I think the name One Arroyo kind of came out of the early process back in 2017, and that was to try to unify the three separate areas of the Arroyo in the city of Pasadena,” said Gould. “And so what was consistent between all three areas was the trail system.”

The Future Of The Arroyo

Beyond these initial restorations, One Arroyo has raised a significant endowment that will fund its continual maintenance, Rothenberg said.

Further maintenance may include repairing some of the smaller feeder trails that connect the various neighborhoods to the main Arroyo path, Gould said.

But, he added that One Arroyo has a more holistic mission.

“We are there to assist the city and the community in looking at the entire Arroyo,” he said. “There are a myriad of projects that our board is looking at as potential places that we can assist the city [with] and really move the Arroyo in a direction that I think we all want to see.”

Some other projects that they are considering include improving the rock walls throughout the Arroyo, not just along the main stretch of the trail. They are exploring the idea of renovating facilities in the Hahamongna Natural Park to use for environmental education programs and potentially restoring an amphitheater that was a part of the Central Arroyo over 50 years ago.

Rothenberg said that no matter what One Arroyo’s next project is, they will decide based on response from community outreach and what the city of Pasadena sees as most beneficial.