Guadalupe Reservoir Reservoir Report

Last Updated: December 5, 2025

Guadalupe Reservoir in California was constructed in 1959 and is located in the Santa Cruz Mountains.


°F

°F

mph

Wind

%

Humidity

Summary

The reservoir is fed by the Guadalupe Creek and is a part of the Santa Clara Valley Water District's water supply system. The hydrology of the reservoir is largely dependent on surface flow from the creek and snowpack providers in the surrounding mountains. The reservoir provides water for agricultural and recreational purposes, including irrigation and fishing. However, due to the ongoing drought in California, the water level in the reservoir has been lower than usual, affecting its ability to meet the water needs of the surrounding communities. Additionally, the reservoir has experienced issues with algae blooms and contamination in recent years, leading to temporary closures for recreational use.

Reservoir Details

Storage 24hr Change -0.21%
Percent of Normal 396%
Minimum 346.0 acre-ft
2021-10-23
Maximum 5.97070623172e+15 acre-ft
2023-04-26
Average 472 acre-ft
Dam_Height 142
Hydraulic_Height 132
Drainage_Area 6
Year_Completed 1935
Nid_Storage 3460
River_Or_Stream Guadalupe Cr
Surface_Area 75
Hazard_Potential High
Dam_Length 695
Primary_Dam_Type Earth
Nid_Height 142
       
Seasonal Comparison
Storage Levels
Pool Elevation Levels
Top Conserv Storage Levels
Inflow Levels

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.

Hazard Potential Classification

High
Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.