San Clemente Dam
This page gives a short history of the San Clemente Dam and description of the planned dam removal project and its environmental impact and related issues and controversies.
Contents
History
The San Clemente Dam was built in 1921 by a local businessman Samuel Morse on the Carmel River to supply the water needs of Monterey's growing population and tourism industry. Later the dam was purchased by Chester Loveland who owned the California Water and Telephone Company (CW&T). To meet the needs of the growing population and increasing demand from the sardine processing industry in Monterey, CW&T built the Los Padres Dam upstream from San Clemente Dam in 1948. In 1966 CW&T sold the dam to California American Water for $42 million. [1] [2] [3].
Geology and Ecology of Carmel River Watershed
Geology and Sedimentation
The Carmel River watershed is on a highly erodable geological formation (filler to be flushed out). Although the dam was built in 1921, by 1947 it was 25% silted and is now 98% silted. [4] Cite error: Closing </ref> missing for <ref> tag
- California red-legged frog
Dam Removal
The San Clemente Dam is set to be removed from 2013 - 2015 due to public safety hazards that could occur in the event of an earthquake or flood in the area.
Reasons for Dam Removal
In the 1990s, California Department of Water Resources (DWR) Division of the Safety of Dams(DSOD) issued a safety order which determined that in the event of the maximum credible earthquake or probable maximum flood the dam would potentially fail creating a public safetly issue [5]. After this report the San Clemente Dam was listed as a high priority public safety issue. An Environmental Impact Report was undertaken to explore the best method for addressing the public safety issues. In 2006 the DWR released a Draft Environmental Impact Report/Environmental Impact Statement (EIR/EIS). The EIR explored CalAm's preferred option of strengthening the Dam and four alternative projects, including the Carmel River Reroute and Dam Removal (CRRDR) option. The CRRDR option had several ecological benefits that the Dam Strengthening option did not have. In 2008 the DSOD stated the CRRDR project would address the dam's public safety issues and other environmental impacts caused by the dam making it the best option for all stakeholders [6].
Carmel River Reroute and Dam Removal (CRRDR) Project:
The Carmel River Reroute and Dam Removal (CRRDR) will provide several benefits for the Carmel River including:
- Permanent resolution to the dam safety concern
- Access for endangered steelhead trout to 25+ miles of spawning and rearing habitat
- Restoration of sediment to the downstream reach of the river and Carmel River State Beach
- Restored ecological connectivity for riparian and aquatic habitats
Project
In order to carry out the CRRDR, access roads are being constructed off of Carmel Valley Road after Carmel Valley Village and before the Sleepy Hollow turn-off. Once the access roads are completed CRRDR construction can begin.
The Carmel river will be rerouted into the adjacent San Clemente Creek a half mile upstream of the dam by cutting a diversion channel through a narrow ridge separating the two channels. The rock created by the diversion channel will be used to block the sedimented reach of Carmel and divert the river into the San Clemente reach. This rock barrier, known as a diversion dike, will essentially create a new ridge along the valley floor cutting off the Upper Carmel reach that is full of sediment. Sediment that has accumulated in the San Clemente reach will be excavated and moved to the Upper Carmel reach. The Sediment that has accumulated directly be hind the dam will also need to be excavated and transferred to the Upper Carmel reach. After the sediment has been excavated and placed upstream of the dam, the sediment slope will be stabilized to stabilize the sediment from being eroded during high flows.
Timeline
As of March 2013, construction is set to begin in 2013, and the estimated completion is set for 2015. Access roads are under construction at this time.
Stakeholders
References
- ↑ CalAm page http://www.amwater.com/caaw/customer-service/rates-information/monterey-san-clemente-dam-removal-project.html
- ↑ History - "Water Over the Dam" by Keith Vandevere http://www.kiracorser.com/ecoart/history/time.htm
- ↑ Carmel Vally Association "Carmel River History"
- ↑ Carmel Vally Association "Carmel River History"
- ↑ San Clemente Dam Removal Project Summary
- ↑ San Clemente Dam Removal Project Summary
Links
Disclaimer
This page may contain students's work completed as part of assigned coursework. It may not be accurate. It does not necessarily reflect the opinion or policy of CSUMB, its staff, or students.
