Thunderbird Park Reservoir

Thunderbird Park Reservoir is an earth dam located in Maricopa County, Arizona, built in 1985. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Thunderbird Park Reservoir

The primary purpose of Thunderbird Park Reservoir is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by City Of Glendale, Cholla Water Treatment Plant (local government). It impounds the Unnamed Wash - Os near Glendale.

The dam stands 44 feet tall and stretches 600 feet across, creates a reservoir covering 2 acres, has a maximum storage capacity of 39 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1985, the structure is 41 years old.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 04/26/2024.

At 44 feet, this dam is taller than 90% of dams nationwide.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Arizona dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateArizona
CountyMaricopa
Nearest CityGlendale
River/StreamUnnamed Wash - Os
Coordinates33.69083, -112.19833

Physical Characteristics

Dam TypeEarth
NID Height44 ft
Dam Height44 ft
Dam Length600 ft
Year Completed1985 (41 years old)

Storage & Hydraulics

NID Storage39 acre-ft
Max Storage39 acre-ft
Normal Storage37 acre-ft
Surface Area2 acres
Drainage Area0 sq mi
Max Discharge75 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeWater Supply
OwnerCITY OF GLENDALE, CHOLLA WATER TREATMENT PLANT
Owner TypeLocal Government
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection04/26/2024
Emergency Action PlanYes

Identifiers

NID IDAZ00204
Federal IDAZ00204
More InfoState Dam Safety Program

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