Stanford officials look to solve Searsville dilemma Palo Alto Issues, posted by Editor, Palo Alto Online, on Jan 17, 2013 at 10:46 am
Stanford University officials are facing a mountain of decisions regarding what to do with Searsville Reservoir, which is slowly filling up with silt, in addition to dealing with a federal investigation for possible violations of the Endangered Species Act.
Read the full story here Web Link posted Thursday, January 17, 2013, 9:51 AM
Posted by stretch, a resident of another community, on Jan 17, 2013 at 11:30 am
I did spend many a summer at Searsville Lake, earned my Girl Scout swimming badges there and lived within hiking distance on Family Farm Rd. for a few years. A beautiful place.
Oregon is removing dams to let fish spawn again. No one ever talks about the town of Searsville that stood pretty much where the lake is. So, a town was moved and the normal flow of a creek was stopped so that San Francisco could have water, and now other species rely on the man-made result. What to do? I say remove the dam and let things go back to "normal".
Posted by Howard, a resident of the Crescent Park neighborhood, on Jan 17, 2013 at 11:39 am
Re "Remove the Dam" -- not a decision to be entered into lightly. Possible increased risk of flooding downstream. Also, removing the silt is a huge issue. I understand we are talking about a steady stream of big trucks carting away the silt, 24 hours a day, 7 days a week, for at least a year -- and where will they dump it?
Posted by Matt Stoecker, a resident of Portola Valley, on Jan 17, 2013 at 12:05 pm
Thanks Sue for writing the article and raising the issue.
Jeff- Acterra is a signatory group on our Beyond Searsville Dam coalition and some folks there are involved with Jasper Ridge and the Searsville Study community group process.
Howard- We agree that dam removal should not be entered into lightly and while we advocate studying this options, along with all others, we would not support a project that compromised the safety of downstream communities. We have consistently advocated for, and offered funding to carryout, a detailed alternatives analysis in order to make the most informed decision. We look forward to working with impacted communities on a preferred option that best meets everyone's needs.
Posted by Steve, a resident of Menlo Park, on Jan 17, 2013 at 12:39 pm
"When life hands you a lemon, make lemonade"
Is there an opportunity here that, while not solving all the problems identified, goes a long way toward mitigating them.
Perhaps the silt should be seen as a resource to be recovered and utilized over the long term rather than as a problem to be gotten rid of all at once. Silt is the type of soil that ever gardener wants, especially in the towns along the bay where clay is the more common soil type. If the silt were dredged and made available through Lyngso and other garden centers, I expect that we would come to see it as a valuable resource to be utilized rather than the "millions of tons of silt" that need disposing.
Removing it at a rate of 5% to 10% per year would allow Searsville Lake to eventually return to health, continuing to provide flood control for the communities below, water for Stanford's irrigation and, perhaps, recreational & educational opportunities for future generations.
Adding a fish ladder to the dam would be the crowning touch as steelhead could once again access the spawning beds upstream from the lake.
Posted by accelerate, a resident of Stanford, on Jan 17, 2013 at 12:57 pm
The problem of the dam has been known for years, but apparently very little progress is being made. The lake is filling up with silt, so they have to do something. Hopefully, the school is devoting enough resources to this project to figure out the best solution well before the situation becomes an emergency.
Posted by Crescent Park Mom, a resident of the Crescent Park neighborhood, on Jan 17, 2013 at 1:49 pm
Steve - I like your ideas...
If dredging Searsville will keep the downstream bridges from flooding in three towns, thus eliminating the need for costly flood insurance and bridge replacements, Stanford should do the right thing and let it happen.
Posted by Alice Smith, a resident of the Green Acres neighborhood, on Jan 17, 2013 at 6:57 pm
My children and I swam in Searsville lake probably 40 years ago. We would have a day out with friends.
Jaspar Ridge research is important to the understanding of a fragile ecosystem. I know that some form of protection for the rainy season (25 -50 or 100 year heavy rains) is needed now and Stanford's ability to alleviate the downstream impact is a critical factor to the planning for flooding. I don't know if the dam should be desilted or decommissioned but will follow the discussions with the SCC Water District, the Joint Powers Authority and Stanford with interest. Thanks to Fred for tine above to the SEarsville Wikilink. Very interesting.
Posted by Mr.Recycle, a resident of the Duveneck/St. Francis neighborhood, on Jan 17, 2013 at 8:34 pm
@Crescent Park Mom & Steve - Maybe Matt Stoecker can adress this directly, but looking at his group's website, they dont want to dredge and build a fish ladder, they want to remove the dam, which absolutely would make the san francisquito creek flooding problem worse.
Posted by Matt Stoecker, a resident of Portola Valley, on Jan 17, 2013 at 9:27 pm
We do support dam removal or notching most of the dam, but only in a manner and with the implementation of other project components that do not elevate the flood risk to downstream communities. We actually support looking at dam removal as part of a larger watershed scale project to improve flood protection downstream and upstream of the dam.
I've actively worked on projects within the watershed since 1998 and since then have advocated for the Highway 101 to Bay creek expansion project starting this summer, the Highway 101 bridge expansion under study, and replacement of all undersized bridges on San Francisquito Creek to reduce flooding downstream. I continue to support these projects and advocate for additional protective measures that also benefit the health of the creek.
Searsville Dam and operations currently do not have any flood control function as documented by numerous recent reports investigating the question. Much of this is due to the fact that the reservoir is full when peak flow events occur, it is almost filled in with sediment, and it it relatively small. The dam does however currently contribute to flooding issue upstream where sediment is backing up tributary streams adjacent to residences. Dam removal options have not yet been studied at Searsville and there is no evidence that removal options would make the flooding problem worse.
We believe that dam removal has the potential to restore historic wetlands and floodplain areas submerged by the reservoir which could reduce flooding downstream as these areas absorb flood flows. The current study is expected to assess this potential. As with other dam removal projects, like on the Elwha River in Washington State and Matilja Dam in Southern California, such a project can be implemented with expanded and revived floodplains and wetlands, downstream bridge replacement, high flow by-pass structures, and improved levees.
We look forward to the study findings and potential for significant flood protection benefits with one or more of the Searsville alternatives being investigated.
Posted by PVrez, a resident of Portola Valley, on Jan 18, 2013 at 9:06 am
The fact is that the trout here are an Endangered Species so legally they need to be a priority.
However, if one's priority was reducing flooding, would dredging out the sediment be the safest, most effective and sustainable option? What if the dam fails? Do you propose it is dredged regularly to keep it free of sediment? Who would pay for it?
Posted by Steve, a resident of Menlo Park, on Jan 18, 2013 at 11:01 am
Thanks for taking time to write this thoughtful response. There are several things you said however that I question and wonder if you could respond to.
First, you wrote "The dam does however currently contribute to flooding issue upstream where sediment is backing up tributary streams adjacent to residences."
I don't understand how the presence of the dam could have any affect on what happens upstream from the lake. Streams coming off the mountain have no knowledge of what's downstream so how does the dam cause sediments to accumulate upstream.
Second, you write "Dam removal options have not yet been studied at Searsville and there is no evidence that removal options would make the flooding problem worse."
If removal options haven't been studied, it seems to me there is no evidence one way or the other regarding its effect on flooding. So you're statement the there is no evidence that removal would make flooding problems worse is nothing more than wishful thinking on your part.
Instead, logic would suggest just the opposite to me. Currently, the reservoir behind the dam is nearly full so it provides little to no flood control capability. We can both agree on that. However, removing the dam entirely would remove what little flood control there is and therefore only increase the likelihood of flooding or, at best, have no effect on flooding potential.
While I look forward to the study of this issue being published, I'm skeptical that we can look to the Elwha River dam for guidance. The Elwha River below the dam flows just 4 miles through National Park before entering directly into the Straits of Juan de Fuca - no population to speak off along this entire length. In contrast, the stream below Searsville dam winds for 12 miles through some of the most developed and expensive real estate on the west coast before emptying into the bay. I don't know how many residents are going to want "high flow by-pass structures, and improved levees" built in their neighborhoods to solve a flooding problem that might be better solved by simply dredging the silt from an already existing dam.
Posted by musical, a resident of the Palo Verde neighborhood, on Jan 18, 2013 at 1:31 pm
@Steve, I had the same question about how sea level rise in the bay could affect flooding upstream in San Francisquito Creek, unless of course the level of high tide rose into those elevations. The explanation I got was that a reduction of the gradient near the end of a waterway will slow the flow there, and this added resistance can slow the flow further upstream than one might imagine. Water coming off the mountain may have no knowledge of the water level in the reservoir, but water sees the water immediately in front of it. If someone far ahead is not getting out of the way fast enough, it can slow down the whole line. Explanations beyond this devolve into boundary conditions, Reynolds numbers, and the Navier-Stokes equation.
Another effect of the dam is that it keeps about 2000 feet of streambed perpetually saturated over a width of several hundred feet. Water flowing into the upstream end very quickly makes its presence known at the downstream end. Yes, if the dam was not at capacity there would be some storage available to slow the flow downstream, but it's not clear that this amount of storage would exceed what unsaturated ground would absorb or otherwise add resistance to the flow.
Good questions. Either we can just try things that seem logical and see what happens, then try something else, or we can wait for what the studies suggest, and then try something else.
I still find this watershed map fascinating -- Web Link
Posted by HUTCH 7.62, a resident of the Old Palo Alto neighborhood, on Jan 18, 2013 at 7:04 pm
Remove the dam save the fish, who in Palo Alto really cares about flooding in EPA anyways. I'm sure those who live near the Newell bridge would be happy to see EPA wash into the Bay....LOL people around here crack me up
Posted by Antigravity, a resident of the Old Palo Alto neighborhood, on Jan 21, 2013 at 11:29 am
The upstream landowners' silt has filled in the reservoir. They should be liable for removing the silt and restoring it to it's original site with appropriate post-fill habitat restoration and erosion mitigation. This can be done for pennies a pound of silt, so cost should not be the issue.
Posted by clc, a resident of Portola Valley, on Jan 23, 2013 at 6:30 pm
Searsville Dam does have a drain valve at the bottom of it. It should be opened and allow the lake to drain completely. At the same time Stanford could run their pumps to fill Felt Lake. Don't worry about silting up the lower creek, steelhead, or redlegged ,frogs, birds, or bats. Let the lake clean itself out, see what kind of mess is down there. The valve could be closed at times for flood control. Reopened again for more clean out. The fish and frogs will continue to hang in there until the best solution is figured out. Doing nothing in the name of further studies is getting to be a lame way out Stanford.
Posted by Eroding confidence in Stanford stewardship, a resident of the Old Palo Alto neighborhood, on Jan 23, 2013 at 9:29 pm
Take a walk on Oak Creek Drive behind the apts and carefully observe the massive collapse of the creek bank in key areas from the December storms
This was aptly forecast in the Stanford financed Sand Hill road widening EIR Hydrology section as a consequence of the the new widened bridges at Sand Hill/Oak Ave, Junipero Serra and Alpine at Webb Ranch
The accelerated flow from these new smooth walled bridges, as opposed to previous "dams" of the original bridges, which previously tended to overflow into the golf course,
is cause for heightened concern
Plus the Natural HazardvDisclosure Statement Disclosures required by state law for all property sales downstream of Sand Hill bridge ALL state that Flooding will occur in Menlo Park and Palo Alto neighborhoods as a result of "Searsville Dam Failure Inundation"
So a lot more study and analysis together with first hand accounts of residents along the creek need to be assessed before anything is done about Searsville Dam and lake
We got lucky ladt month due to low tides during the heaviest runoffs.
Climate change gurus attest to more extreme events in this current global warming cycle