Water Quantity
Tempe began filling the 220 surface-acre lake on June 2, 1999, and declared it officially full on July 14, 1999. The City purchased water for the initial fill from the Central Arizona Project, which delivers water statewide from the surplus in the Colorado River. This water was delivered through the Salt River Project Canal System. Using technology, the City of Tempe has minimized the amount of water lost to seepage. A flood levee forms an impenetrable wall around the sides of the lake. This levee was covered with a structural and aesthetically attractive lake edge. Underground, a clay wall connects to bedrock underground at the west end. On the east end, a seepage recovery system recovers almost 100 percent of the water that seeps into the ground. Water is recaptured by 10 wells around the eastern portion of the lake and pumped back into the lake. Eight bladders form two inflatable dams that contain the water on the east and west ends of the lake and can be deflated or inflated in 45 minutes to release overflow water or catch flood tail water. Water released during storms is replaced with the tail waters from water released from the lakes upstream. Water from evaporative losses will be replaced primarily with Central Arizona Project water and recharge water exchanges.

The City of Tempe relies on renewable and sustainable water supplies, with a diverse mix of water resources available to meet the needs of our water service area. This means that Tempe does not use groundwater in excess of what is naturally or artificially recharged back into the aquifers, preserving that water for years when droughts do occur and there is a shortage of surface water supplies. Tempe is committed to continuing this strategy in keeping with the goals of the Groundwater Management Act passed by the Arizona Legislature in 1980. For more information go to using Town Lake water efficiently.

Current weather conditions and current water temperature at Town Lake.

Town Lake Water Flow
Tempe Town Lake is part of the Salt River channel and as such, is subject to receiving water from upstream. When snow melts from the north or rains fall across our state, water is released from the SRP dam systems into the Salt River and then Tempe Town Lake.

Here is a general guide to understanding water flows to Town Lake:
Flows under 10,000 cubic feet per second (cfs) normally do not result in any change to standard operations at Town Lake. If flows exceed 10,000 cfs, the City of Tempe would expect some debris to pass and would address that situation. The lake level would be expected to remain constant. If flows exceed 30,000 cfs, dams would be lowered partially, then adjusted to any increased flow thereafter.

The gauges at Priest Dr. and Curry Rd. account for the water passing through Tempe Town Lake. Anyone can monitor the water flow in current time by clicking on Salt River at Priest Dr. and  Indian Bend Wash at Curry Rd.  

Town Lake has been hailed as a model to forward thinking, progressive planning and efficient water management.