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Project: Santa Ana River Mainstem (SAMO)

Description: Santa Ana River Mainstem Project provides 100-year flood protection to over 3.35 million people in the growing urban communities in Orange, Riverside and San Bernardino Counties. Covering 75 miles, starting from headwater of Santa Ana River east of City of San Bernardino to the mouth of the river at the Pacific Ocean. The Project includes seven independent features. Project also includes environmental features to provide wetland habitat for federally listed endangered species. The plan provides for the acquisition of mitigation lands, restoring temporary loss of habitat values, cultural mitigation, and a 32-mile system of recreation trails.

Reference Number: 3860-PM-066

Implemented By: Orange County Flood Control District

Objective: Increase flood protection to residences and businesses. Includes significant environmental enhancement features.

Type: Restoration, Recreation/Access/Interpretation, Infrastructure Improvement

Total Cost: $2,386,826,868.25

Project Status: Project Implementation

On Time?: Yes    Within Scope?: Yes    Within Budget?: Yes

Estimated Completion: 12/31/2032    Actual Completion:

Associated Counties: Orange

Contribution SourcesContribution DateContribution Amount
Federal Contribution12/18/2018$1,584,500,000.00
Local Contribution6/3/2016$263,670,000.00
Other State Funds12/18/2018$219,874,244.00
Prop. 84, Flood Control Subventions Program8/28/2013$31,782,624.25
Prop. 1E, Flood Control Subventions Program6/3/2016$287,000,000.00

Project MetricMetric TopicQuantityUnit
RestorationErosion Control  
RestorationRiver Channel Restoration2880acres restored/assessed/managed
Infrastructure ImprovementDam Modification  
Infrastructure ImprovementFlood Control Subventions  


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