Sweeping views of the San Francisco Public Utilities Commission’s Peninsula Watershed and rolling green hills home to several endangered species are among the experiences those trekking on the Fifield-Cahill Ridge Trail can expect on one of the docent-led events offered on the 10-mile route.

Extending from trailheads at Skylawn Memorial Park in San Mateo to a terminus at Sneath Lane in San Bruno, the Fifield-Cahill Ridge Trail has offered a rare look at the commission’s watershed lands and the Crystal Springs, Pilarcitos and San Andreas reservoirs for 15 years.

Fifield-Cahill Ridge Trail

The 10-mile trail connecting Skylawn Memorial Park in San Mateo to Sneath Lane in San Bruno opened to the public some 15 years ago after a yearslong, collaborative effort between the San Francisco Public Utilities Commission and several environmental groups in the region.

But the public hasn’t always had access to the gravel service road and the educational opportunities that have accompanied the opening of the trail in 2003. Because of the trail’s proximity to a watershed holding nearly 30 billion gallons of drinking water, the effort to make it available to the public took years as officials developed a plan for protecting the water quality as well as endangered and native species that inhabit that stretch of the ridgeline, said John Fournet, community liaison for the SFPUC’s Natural Resources and Lands Management Division.

By limiting trail access to three days a week and to those who make reservations in advance to go with trained volunteer trail leaders, Fournet said officials were able to find a way to balance stewardship of the watershed and the benefits of giving the public access to the land.

‘This has always been something the community has wanted to do,” he said. “We were able to come up with a program that mitigated potential environmental impacts and it’s been great to work with our 300-plus volunteers and also great to have close to 20,000 participants to get out there.”

Fournet credited volunteers from a variety of stakeholder groups — including the Bay Area Ridge Trail Council, the Committee for Green Foothills, the California Native Plant Society and the Golden Gate Audubon Society, among others — in helping carry out managed access to the trail. He said fire is among the biggest threats associated with giving hikers access to the land, but with the help of hundreds of volunteers to monitor hikers as they enjoy the trail, they’ve been able to maintain the quality of the water and protect the state- and federally-endangered species such as the California red-legged frog, the San Francisco garter snake and the Mission blue butterfly.

“The trail leader volunteers are the living, breathing trail mitigation,” he said. “They’re the ones that actually allow us to do the program without impact.”

As the southern end of an 80-mile stretch of continuous ridgeline trail extending from Marin County, the Fifield-Cahill Ridge Trail establishes a critical connection in the Bay Area Ridge Trail, said Janet McBride, executive director of the Bay Area Ridge Trail Council. Extending as far north as Mount St. Helena and as far south as Gilroy, the Bay Area Ridge Trail will be a 550-mile loop around the Bay Area once complete, said McBride.

With the goal of connecting people with open space near where they live, several members of the council have been enthusiastic about volunteering as trail leaders for the Fifield-Cahill Ridge Trail, said McBride. She added the program the SFPUC developed with input from environmental and community groups to manage access to the watershed has served as a model for other sensitive environments, and commended the time-intensive effort to allow public access there.

“It was a very big deal, it was a hard-won effort,” she said, of the opening of the trail in 2003. “It’s definitely part of a beautiful, long [and] connected stretch.”

As one of the most sensitive environments and remote parts of the Peninsula Watershed, the Fifield-Cahill Ridge Trail and other parts of the watershed contain fewer invasive species than other open spaces in the county, making them a valuable resource for education programs, said Lennie Roberts with the Committee for Green Foothills. As an advocate for access to trails and parks in the county, Roberts acknowledged the SFPUC’s role in balancing multiple priorities for the land.

“I think people actually get a learning experience as well as a recreational experience, which is always a good thing,” she said.

Fournet expected the educational benefits of the trail to grow with a planned 6-mile extension to the Golden Gate National Recreation Area’s Phleger Estate, which is currently undergoing environmental review. He said officials are in the process of developing a master interpretative plan for the property and implementing it on the existing and new trails once the extension is completed.

“It’s representative of that type of ecosystem on the coast, but it’s probably one of the more intact and least disturbed,” he said. “The experience of that area has been invaluable.”

Visit sfwater.org/index.aspx?page=147 for more information on the Fifield-Cahill Ridge Trail. Visit sfwater.org/trails to reserve a spot one of the docent-led events or hikes on the trail.

(650) 344-5200 ext. 106

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(11) comments

Nancy Reyering

Lennie Roberts has long been a staunch advocate for public access, and has the successes to prove it. Her work preserving access to the coast and Bay include the current battle at Martin’s Beach where billionaire Vinod Khosla closed off historic access. And as one of the Founders of Midpeninsula Regional Open Space District, she has enabled people from all walks of life to hike, bike, and ride horseback on 225 miles of trails.

The Crystal Springs watershed is a protected area for good reason. It’s not only our drinking water, but also has the highest concentration of rare, threatened, and endangered species in the Bay Area and is a State Fish and Game Refuge.

Because of the delicate nature of the Watershed, and because the reservoirs hold nearly 30 billion gallons of drinking water, the SFPUC developed and adopted the Peninsula Watershed Management Plan, which establishes the framework in which additional education and public access improvements are considered.

“The SFPUC takes our environmental stewardship responsibilities seriously, and we are proud to share this treasured natural resource with the community in a responsible manner,” said SFPUC General Manager Harlan L. Kelly, Jr. “For the past 15 years, we have managed the Fifield-Cahill Ridge Trail in a way that provides public access while also protecting the ecosystem and our local water supply, and creating education opportunities for trail users to learn about the watershed.”

Trail volunteers on the Peninsula Watershed are trained conservation leaders who lead excursions on foot, mountain bike, or horseback three days a week. To date, 315 trail volunteers have lead nearly 2,000 trips on the watershed, with more than 5,500 users benefitting from the program. The SFPUC carefully monitors trail use by the public to ensure that there are no significant impacts to the fragile ecosystem.

Since the late 1800s, more than 23,000 acres of land on the Peninsula have been protected to support local water supply, which includes the Pilarcitos, San Andreas and Crystal Springs reservoirs.


EBMUD's 59,000 acres of beautiful watershed lands and reservoirs in the East Bay and Sierra Foothills protect water quality for EBMUD customers.

An oasis for wildlife and a lush haven for people, these lands offer many opportunities to explore and enjoy nature.
Explore East Bay watershed lands

In the East Bay, the shores of Lafayette Reservoir and San Pablo Reservoir offer great spots to picnic, walk, birdwatch, boat and fish. Along 80 miles of East Bay trails, hikers and horseback riders can soak in lake views and streams, redwoods, wildflowers and open grasslands. In July 2018, two trail segments were opened to mountain biking; learn more!



As expected, the usual fear and 1/4 truths are trotted out to defend the irrational exclusion of people from the westernmost stretch of the watershed lands.
Ca 280 is directly next to Crystal Springs Reservoir,Ca 92 crosses over the Crystal Springs Reservoir....to suggest that non motorized visitors 3-4 miles away will severely impact the watershed is laughable.

The Fifield-Cahill trail(fireroad)is composed entirely of westward facing slopes and the ridiculous notion that this trail(fireroad),if opened to non docent required access will impact fragile habitat is ludicrous.
Fifield-Cahill is miles from Crystal Springs Reservoir or Pilarcitos dam.

Bringing in 7 day a week,dawn til dusk yearly permitted stakeholder policy will greatly complement SFPUC staff by protecting this land from the current illegal pot farms and ATV trespassers, who BTW also support keeping the good people away so they can trespass unhindered.

I wholeheartedly agree with CGF in many areas of preservation,but CGF,Native Plant and Loma Prieta Sierra club are dead wrong in opposing consideration of even a yearly permit system that visitors would secure to visit the Fifield-Cahill trail w/o a reservation and docent accompanying requirement.


People who believe that this land should become more knowlegable to the decision process done previously. Access to these lands is a privilege not an entitlement.


People who believe that access to these lands is a privilege not an entitlement should research the definition of publicly funded open spaces.
Bringing in stakeholders rather than deterring them will greater protect these 23,000 acres whereas now every year it is a haven for illegal pot farming,illegal ORV intrusion.




One major problem with the docent led Fifield-Cahill Ridge Trail hikes is that to my knowledge, it is a one-way hike, either from 92 to the Portola Gate or reverse and the hikers have to juggle cars so everyone can get back to their cars.

As a regular hiker on Sawyer Camp Trail and Sweeney Ridge, among numerous other local trails, I fail to understand the arguments for how this area has been kept closed to hikers and even fishing for so long. AFAIK, EBay MUD allows hikers and fishing along their reservoirs. Why is it OK for them but not for the SF owned land? No one has been poisoned from the water in the East Bay, have they?

I'd like to see a trail connection from Portola Gate to North Peak and also into the southern portion of the Rancho Coral De Tierra area by El Granada.

Below is a link to a much better written article on the subject of opening up the Peninsula watershed from a few years back. At that time, the article said that big changes were coming soon and that the Fifield-Cahill Ridge Trail was going to be opened to hiking. Three years later and it all looks like the usual head fake from SF Water.

The Peninsula Watershed: To Open, Or Not To Open?
by Nathaniel Dolton-Thornton
August 20, 2015

Isn't there someway to sue SF Water to force them to open the watershed?

vincent wei

How many years has this taken? It surely was an issue before 2003.

Hasn't the self-anointed Committee for Green Foothills fought against public access for years now?

I know they have fought to stop any kind of improvements to what is an unsafe road - highway 92.


Hikers do not post a fire hazard. The five homes for public employees who live on the land have power lines - that is an unecessary fire hazard! This is the exact kind of illogical rhetoric and unscientific fear-mongering that results in loss of a tremendous public asset. It's time to move past the fear use science and open the SF watershed from sunrise to sunset just like all the other watersheds. Just like the reservoir at Hetch Hetchy. The article fails to mention the water is filtered after the reserviors, the sane reserviors are surrounded on the Eastside by a freeway less than 20 feet away from the water. Closing ridge lines that are a mile away is ridiculous.


I am again disappointed With the daily journal is reporting on this topic. Once again the “local paper” takes the partly line from The City. With no mention of historical context, or even outreach of any kind to ilk like mine. Who have been organizing democratically for years.

Some facts of history and science that the author might want to consider putting in for context? How about these

-The Watershed was closed in 1930 to the public the city of San Francisco when a private water company was reborn as the SF Water Department. Sparking deceases and decades of democratic uprising in San Mateo County.
-The trail in question is the original route for Skyline as the bond in 1919 paid for, and homestead land before that (Cahill-Fifield is a historical trail, like Sawyer Camp)
-Alitotto promised to “Open the Watershed” in 1968, but lied after getting what he wanted out of the alignment of 280. Does anybody in San Mateo County remember? Does this paper remember?
-The EIR 2002 CEQA document on Cahill-Fifield clearly says normal pedestrian access is fine. Scientifically to threatened species in this area. In 2003 the powers that be chose the most restrictive option of me fo in 2003 the powers that be chose the most restrictive option of 4, the “docent option”. The other options for just scientifically feasible. Meaning the language from Fournet here can be read as tax payer sponsored fear mongering. And the paper complicit for only having this comment section as a counterbalance.
-The Trail in question opened to docent access after a 15 year (or so) long political fight. Led by people on San Mateo County to petition the ear of those in power in San Francisco.
- lastly I was in your offices to try and tell you guys about the link below where I prove all this and much more. One of your sales guys told me he “knew about the Sea Lions in Crystal Springs already”. Ok...

Are you not the newspaper, you don’t have a history section? You do, but you do not know your history.


15 years of guided tours and reservations...enough already!
The time has come for a dawn til dusk open gate access for the non motorized public.
This "trail"(fireroad) is miles away from the Crystal Springs reservoir, protecting water quality from non motorized visitors when Ca 280 and Ca 92 cross directly next to and over the reservoir?
Crystal Springs reservoir sits a stone's throw away from Ca 280,the statement that protecting water quality as the main concern is inaccurate.
There is more non reservation public access to Hetch Hetchy reservoir,which is the source of Crystal Springs water,than this Fifield-Cahill fire road that sits 4-5 miles from the reservoir.

Identifying Lennie Roberts as an "advocate for access to trails and parks in the county" is a cruel joke,she has done everything within her power to prohibit dawn til dusk access w/o reservations to this public space,she is not a public access advocate.
The Fifield-Cahill tr connects to Sweeney Ridge above Pacifica,not Sneath Ln, which is where you encounter a closed gate ,then you must turn around and walk back to Ca 92.....ridiculous.

SM Daily Journal,please broaden your scope of interviewee's next time you formulate an article on the Crystal Springs Watershed, possibly speaking to other advocates that look to broaden access parameters that don't require months of planning and an anointed guide to walk-ride horses or bicycles on fire roads the public pays for.

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