Goodwin Dam

Goodwin Dam
Name	Goodwin Dam
Country	United States
Location	Arizona
Status	Operational
Owner	Bureau of Reclamation
Operator	Salt River Project
Dam type	Concrete gravity
Dam height	174 ft
Dam length	1,200 ft
Reservoir	Roosevelt Lake
Reservoir capacity	1,653,000 acre-feet
Opened	1909

Goodwin Dam

Goodwin Dam is a major concrete gravity dam on the Salt River in central Arizona. It forms Roosevelt Lake and is integral to water storage, flood control, and hydroelectric generation for the Phoenix Metropolitan Area, Pima County, and surrounding communities. The structure is operated within a network of Southwestern water infrastructure including projects by the United States Bureau of Reclamation and the Salt River Project.

Overview

Goodwin Dam is part of a cascade of dams on the Salt River that includes Roosevelt Dam, Horse Mesa Dam, Mormon Flat Dam, and Cherry Creek Dam. It contributes to the regional water supply managed under the Reclamation Act of 1902 and the Arizona Groundwater Management Act of 1980 framework. The site interfaces with federal agencies like the U.S. Forest Service and state entities such as the Arizona Department of Water Resources and municipal utilities in Phoenix, Arizona, Scottsdale, Arizona, and Tempe, Arizona.

History and Construction

Plans for reservoir storage on the Salt River date from proposals by early twentieth-century engineers working with the United States Bureau of Reclamation and proponents like Theodore Roosevelt's conservation movement. Construction began following authorization in regional reclamation acts and local voter-approved water initiatives; contractors included firms that previously built western dams connected to projects such as the Hoover Dam and Glen Canyon Dam. The project saw phases overlapping World War I and the interwar period, with labor drawn from nearby mining towns and railroad hubs like Phoenix (Valley of the Sun), Globe, Arizona, and Maricopa County. Subsequent retrofits paralleled upgrades at Roosevelt Dam and coordinated operations with the Salt River Pima–Maricopa Indian Community water agreements.

Design and Specifications

Goodwin Dam is a concrete gravity structure with a crest length and height engineered to impound Roosevelt Lake's active and dead storage. The dam includes gated spillways, low-level outlet works, and penstocks feeding a hydroelectric powerhouse modeled on designs used at Glen Canyon and Hoover facilities. Instrumentation follows standards promulgated by agencies involved in the National Dam Safety Program; structural materials and concrete mixes were selected with reference to projects like Hoover Dam and flood-control works on the Colorado River. The reservoir capacity and surface area influence allocations under interstate compacts such as the Colorado River Compact and state water rights adjudications in Arizona v. California-era settlements.

Operations and Water Management

Operational control centers coordinate releases to satisfy municipal water deliveries to Salt River Project service areas, agricultural diversions for irrigators in Pinal County, and downstream flow requirements set by federal mandates and agreements with tribal nations such as the Gila River Indian Community. Hydropower generation schedules are balanced with peaking needs for utilities including Arizona Public Service and regional grid operators like Western Electricity Coordinating Council. Drought contingency operations align with modeling from the Bureau of Reclamation and the U.S. Geological Survey, and water accounting interacts with groundwater recharge programs in metro areas administered under Arizona Department of Water Resources planning.

Environmental and Ecological Impacts

The dam altered preexisting riparian corridors used by species protected under statutes like the Endangered Species Act; habitat changes affected populations of fish native to the Salt River and migratory birds on the Sonoran Desert wetlands. Management measures have included cooperative programs with conservation organizations such as The Nature Conservancy and regulatory oversight from the U.S. Fish and Wildlife Service. Sediment trapping at the reservoir changed geomorphology downstream, with research collaborations involving academic institutions such as Arizona State University and University of Arizona assessing impacts. Mitigation initiatives reference precedents from ecosystem restoration projects on the Colorado River and riverine restoration efforts tied to the Central Arizona Project.

Recreation and Public Access

Roosevelt Lake formed by the dam is a regional recreation destination serving boating, sport fishing, and camping; visitor services coordinate with the U.S. Forest Service and Arizona state parks systems linked to sites like Tonto National Forest and nearby state recreation areas. Recreational species management and angling regulations involve the Arizona Game and Fish Department and local outfitter associations in Maricopa County and Gila County. Access roads connect to state routes and federal highways including U.S. Route 60 and Arizona State Route 188, supporting tourism tied to nearby attractions such as Saguaro National Park and heritage sites in Payson, Arizona.

Cultural and Economic Significance

Goodwin Dam's contribution to water security underpins agricultural development historically associated with Salt River Valley reclamation and the growth of metropolitan centers like Phoenix. Economic linkages include hydropower revenue streams to utilities like Salt River Project and job creation during construction periods comparable to other Southwestern infrastructure projects administered by the Bureau of Reclamation. The site intersects with Indigenous water claims and cultural landscapes involving tribes such as the Salt River Pima–Maricopa Indian Community and Gila River Indian Community, and it features in regional planning debates alongside initiatives like the Central Arizona Project and metropolitan water reuse programs championed by local governments and institutions including Maricopa County and municipal water authorities.

Category:Dams in Arizona Category:Buildings and structures in Maricopa County, Arizona