In this story from today’s Bee the spillway option to release more water from Folsom Lake to prevent flooding is explored and looks to be very workable, and can be done fast. However, the use of the American River running through the Parkway as a flood control channel, while necessary now and in the near future, should not be the long-range goal as the power of the water running high and fast through the Parkway causes a lot of damage and threatens the integrity of the Parkway.
This is why our preferred long-range solution is the Auburn Dam and the raising of Folsom Dam, the goal being to hold more water and not have to release it during heavy run-off, which has other positive consequences including increasing recreational opportunities, and access to water during dry years for the salmon run.
That being said, it still makes a lot of sense to build this spillway. As we learned with the building of Folsom Dam, (which filled in the first week after an unforeseen big storm) big dams have a history of not being big enough, and the spillway is the kind of back-up that is vitally needed.
Here is an excerpt.
Cheaper Folsom Dam fix?
Spillway plan could provide 200-year flood protection sooner, federal report says.
By Matt Weiser -- Bee Staff Writer Published 12:01 am PDT Friday, June 16, 2006
A new spillway at Folsom Dam could double Sacramento's flood protection -- and do so up to nine years sooner and $650 million cheaper than previous plans.
Those are the key findings of a federal report announced Thursday, almost exactly one year after high bids shelved a plan to enlarge existing river outlets in the dam.
The new spillway would be built just south of the present main dam. A 1,700-foot-long concrete chute, the spillway would provide an additional way to dump floodwaters from Folsom Dam into the American River during severe storms.
As proposed, the spillway would have six gates located about 100 feet below Folsom Lake's maximum surface elevation, allowing dam operators to release floodwaters much sooner to accommodate greater upstream runoff.
The new report, called a Project Alternatives Solution Study, was produced jointly by the U.S. Bureau of Reclamation and Army Corps of Engineers.
It is an engineering feasibility study that still needs refinement. The dimensions of the structure and its cost are estimates.
But it confirms the spillway can meet Sacramento's flood-control needs.
"We know now that a joint federal spillway project is a viable solution," said Col. Ronald Light, district engineer for the U.S. Army Corps of Engineers.
The project would give Sacramento at least 1-in-200-year flood protection, or the ability to withstand a storm with a one-half percent chance of happening in any given year.
The project represents an unprecedented degree of cooperation between the federal agencies, shaving years off the planning process.
