Keeping Up with Demand

In the 1930s, federal funding allowed water service to expand into the suburbs, and during the 1940s, an increased use in evaporative coolers created a higher demand for water.

In the last three months of 1940, wet weather created the largest runoff in seven years, and this runoff ended a record drought. The ending of the drought was celebrated on April 26, 1941, on which day Governor Sidney Osborn declared it a “Day of Thanksgiving for Water.”

A postwar increase in population and a surge in economic conditions in 1946 caused a critical water shortage in Phoenix and city officials began to look at options. The Arizona Republic reported that fire protection in the summer was inadequate because high demand caused pressure to drop significantly.

In September 1946, the water development committee presented the idea of making major improvements to the Phoenix water system, which would include improving the distribution system, the Verde River water intake, constructing the gates at Horseshoe Dam, and building the very first water filtration plant. The bonds to fund the projects, which were about $5 million, were overwhelmingly approved by voters in November of that year.

In June 1947, the city awarded the contract for the construction of the Verde Water Treatment Plant for $1.16 million. And after a new right-of-way was negotiated with the Salt River Indian Reservation, the plant began delivering water to Phoenix in 1949.

However, because of much political wrangling over Verde River water rights and future Central Arizona Project issues, the gates to the Horseshoe Dam were not completed until June of 1950. And although the gates, which would provide an additional 23,000 acre-feet of water, took a while to complete, the effect of giving Phoenix additional water to utilize during the peak demands of summer would benefit Phoenix for many summers to come as the desert city grew.

In 1952, the city of Phoenix signed a contract with Salt River Project (SRP) known as the domestic water service agreement. That same year, the city constructed a water treatment plant on the Arizona Canal near 24th Street. The plant, which was then known as the Squaw Peak Water Treatment Plant, now the 24th Street Water Treatment Plant, began delivering water to residents in 1953.

In 1957, the Phoenix water system began expansion into northern, western, and southern areas of the city that had recently undergone annexation. Phoenix voters approved a $35 million bond sale so the city could enhance the water system and purchase private water companies in the recently annexed areas. The bond sale also included an expansion of the Squaw Peak Water Treatment Plant, and the construction of a new reservoir.

In 1959, Phoenix and Mesa entered into an agreement to purchase land from the Val Vista Investment Company for a jointly owned water treatment plant. Before the plant could be built, Mesa needed to enter into a domestic water service agreement with SRP.

Then after a dozen years, in 1971, Phoenix and Mesa requested a funding grant from the U.S. Environmental Protection Agency as part of the recently created Clean Water Act. The grant was requested to assist in the construction of the Val Vista Water Treatment Plant. Construction began in 1973 and water deliveries began in 1974.

Meanwhile, Phoenix continued to grow in the west valley. In the late 1950s John F. Long began developing the community of Maryvale, and along with the growth, the demand for water began to increase on that side of town. As a result, in 1961, Phoenix purchased land near the Arizona Canal to build what would soon become the Deer Valley Water Treatment Plant. The plant began supplying water to citizens in 1964.

Also in 1961, the city authorized an expansion of the Squaw Peak WTP, and the addition of more reservoirs at city plants and elsewhere. Meanwhile, the city continued to purchase private water companies and add service connections.

In 1964, total water production capacity for the city of Phoenix reached 360 MGD.

In late September 1968, the law was signed that paved the way for the Central Arizona Project (CAP) to begin. Groundbreaking for the CAP began in May 1973, although it would take another 12 years for Colorado River water to reach Phoenix. The CAP proved crucial to providing a water supply for non-agricultural lands outside the boundaries of the Salt River Project that did not have surface water rights from the Salt and Verde rivers.

In 1980, as part of Arizona’s compliance with federal requirements regarding authorization of CAP allocations, state officials created the Arizona Groundwater Management Act, and along with it, the Arizona Department of Water Resources. This act restricted Phoenix’s ability to pump groundwater as before. However, because of the completion of the CAP in the Phoenix area, the city would now have a third surface water source.

The Union Hills Water Treatment Plant, which was the first water treatment plant to treat CAP water, was completed in October 1985.

In 1987, Phoenix joined a group of other Valley cities to negotiate improvements to dam safety in the wake of disastrous floods that struck the Salt and Verde Rivers in the late seventies and early eighties. The final project was known as "Plan 6.” It included adding height to Roosevelt Dam, and constructing the New Waddell Dam to increase water storage at Lake Pleasant. The Valley cities pledged funds to speed construction of the dam safety project, and after its completion, received rights to floodwaters that might be captured by the modified structures.

Phoenix and other Valley municipalities also paid for the SRP/CAP interconnect that would allow SRP facilities to accept CAP water into the SRP system, providing even more flexibility in treating and delivering water to Phoenix residents. The SRP/CAP interconnect also served as a necessary first step in facilitating the ability to recharge water into the ground in order to replenish groundwater supplies. The Arizona Legislature created the legal authority for water recharge projects in 1986 and in 1987 CAP began construction of projects that would allow Arizona to store excess Colorado River water in the ground for future use. By 1993, the SRP/CAP interconnect enabled Valley cities to construct the Granite Reef Underground Storage Project (GRUSP) downstream of the interconnect in the Salt River.

Last modified on 12/19/2007 09:24:08