Many of you have been wondering: What’s Next for the Matilija Dam?
Overall, the next step to take down the dam is to identify and secure funding to complete the necessary engineering and environmental permitting to get the project “shovel ready.”  This work will likely take another couple of years.  Several stakeholder organizations have formed a funding subcommittee to collaborate and take the steps necessary to remove the dam in a reasonable time frame.

In the mean time, here are some updates on the latest accomplishments of the Matilija Coalition courtesy of Paul Jenkin’s blog on http://matilija-coalition.org/ and  venturariver.org

May

In the beginning of May, the Matilija Coalition got exciting news as another grant has been approved for the Matilija Dam Ecosystem Restoration Project.  $5M from the state Wildlife Conservation Board will fund final design and engineering for the removal of the dam as well as downstream levees.  This funding will keep the project moving forward after the current work under a $3.3M California Department of Fish and Wildlife (CDFW) grant is completed in 2021 and get these projects “shovel ready.”

July

Back in July, the Matilija reservoir was drained in response to safety concerns and liability resulting from the recreational use of the dam site.  The 12″ valve controlling the dam outlet was opened on the morning of Wednesday, July 1, releasing flows of approximately 30 cubic feet per second downstream.  The valve will remain open maintaining the reservoir in a drained state until the winter rains.   

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Images of the drained reservoir reveal the degree of additional sedimentation since the Thomas Fire, which has reduced the storage capacity of the dam to less than 150 acre feet.  The initial flush released relatively clear water, but downstream water quality degraded as flows began to cut a channel through the sediment.  The long term effects of drawing down Matilija Reservoir are evident in the series of photos taken at Camino Cielo. 

 

The slow downcutting and meandering of the stream channel through the sediment in the remnant reservoir mobilizes fine sediments and transports them downstream.  During the summer months flows are low and decreasing until the next rains come in November or December.    These “suspended sediments” are deposited on the streambed, with significant implications for the ecosystem.  Fish spawning and rearing habitat and the benthic organisms that form the foundation of the food chain are impacted by fine sediment.  This is why the dam removal planning analysis has been focused on timing sediment release with a large storm event so that the fine sediments will be transported to the ocean during high flows. For more information, check out the full article

September

Announced on September 1st, the Matilija Coalition has commissioned a report from the Bay Area Council on the economic benefits of the Matilija Dam removal. The results found that the dam removal would result in around 2,300 new jobs and $350 million dollars in economic output. Check out the full article for more information