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San Vicente Dam Raise

The largest RCC dam raise in the world ensuring a long-term sustainable and dependable water supply for the San Diego region.

San Diego County Water Authority |  San Diego, California

Introduction

In the early 90s, the San Diego region was importing in excess of 90% of their water from hundreds of miles away through a series of complex intrastate aqueduct systems, including pipelines, tunnels, and pump stations. These systems were at constant risk of natural disasters ranging from wildfires to earthquakes, as well as, projected global climate change effects and California’s extended drought.

To mitigate the legion of risks, the San Diego County Water Authority (SDCWA) took proactive measures to ensure their community would have an adequate and dependable supply of local water storage. They would implement a 20-year, $1.5 Billion Emergency and Carryover Storage Project.  The final phase of the project was concluded in 2015 with the completion of the San Vicente Dam Raise – the highest roller compact concrete (RCC) dam raise in the world.

 Project Scope

This final phase of the Emergency and Carryover Storage Project, was the 35.7 meter (117 foot) raise of the existing 67 meter (220 foot) high San Vicente Dam. This existing water storage dam would be raised using roller-compact concrete (RCC) in order to save time and money. This method of construction enabled the team work 24-7 because of the fast placement schedule of RCC. RCC has a fast construction schedule because the zero-slump concrete is able to support heavy construction equipment immediately after placement.

Height of original concrete gravity dam, in feet

Dam Raise using RCC, in feet

Height of completed dam, in feet

Highest Dam Raise in the World using RCC


Reaching new heights at San Vicente

International Water Power & Dam Construction highlights the San Vicente Dam Raise. MWH experts, Glenn S. Tarbox, Gerard E. Reed III and J. Wade Griffis, provide details on the largest raise of a concrete dam in the US, and the highest raise using RCC in the world.

Read the full version of Reaching new heights at San Vicente.

Project Challenge

The San Vicente Dam is in an area of the United States at high risk for earthquakes. To mitigate this risk, the dam was optimized to reduce the impacts of seismic motions, including a smoothly varying downstream face to eliminate stress concentrations. The dam can withstand an earthquake of 7.5 magnitude on the nearby Elsinore Fault, ensuring at times of natural disaster the local population will still have reliable access to water.

 

Project Solution / Result

The completed San Vicente Dam now stands at 102.7 meter (337 feet) tall and is the largest dam raise of its kind in the world.

The dam raise project added 152,000 acre-feet of water storage to San Vicente Reservoir. This reservoir combined with the two other projects in the Emergency and Carryover Storage Project, Olivenhain Dam and Lake Hodges, now provide the region with more than 90 days of emergency water supplies.

Awards and Acknowledgements 

2016 Project of the Year – Structures >$75 million

APWA (American Public Works Association – San Diego Section) 

2016 Project of the Year Award – Dams & Reservoirs

ASCE (American Society of Civil Engineers – San Diego Section)

2016 Project Achievement Award – Public Works >$15 million

CMAA (Construction Management Association of America – San Diego Chapter)

2016 Excellence in the Constructed Project

USSD (United States Society on Dam)

2016 Global Best Project – Award of Merit for Water/Wastewater

ENR (Engineering News Record)

2016 APWA San Diego and Imperial Counties Chapter Project Award

APWA (San Diego Section)