SEASONAL WATER SUPPLY AND QUALITY UPDATE

Carmichael Water District has two primary water supplies, surface water from the American River and groundwater from the underground aquifer referred to as the North American Subbasin. The coordinated management of surface water and groundwater is known as conjunctive use practice and has been implemented in California and in Carmichael since the 1950s when groundwater wells were constructed. Similar to Sacramento regional partners, conjunctive use balances the limited water resources to ensure a sustainable American River ecosystem and reliable water supply. The District’s conjunctive use practice  maximizes surface water usage in the winter and spring months when surface water supplies are abundant, but during the hot summer and fall months the District shifts usage to leverage banked groundwater supplies. The current extreme drought conditions have resulted in the District receiving curtailment orders from the State Water Resources Control Board restricting the District’s use of American River supplies. A curtailment order is a legal mandate from the State Water Resources Control Board (State Water Board, or Board) directing a water right holder to stop (curtail) their diversions.

While the District continues to practice conjunctive use to ensure sustainability and reliability of our water supplies, we also focus on our fiduciary responsibilities by seeking out revenue generating opportunities for our customers. This includes participating in water transfers and water sales. Through conjunctive use and water transfers, the District can be an effective partner in the Sacramento Region by providing water supplies to other water agencies lacking sufficient water supply, while generating revenues for investment into District infrastructure improvements to increase the District water system reliability and drought resiliency.

The following details provide further information regarding the water supply balancing process, benefits, and potential temporary water aesthetic changes:

Groundwater Characteristics

  • The District typically increases its use of groundwater during the summer months
  • Groundwater is generally considered harder than surface water
    • This is due to a greater mineral content than surface water
    • In some cases, groundwater can cause mineral deposits to appear on glass and metal
    • When using soap, groundwater does not form a lather, or suds, as easily as surface water
  • At times groundwater can appear cloudy, milky, or white which most often results from air in the water.  These tiny air bubbles are harmless and have no effect on the safety or quality of the water. After filling a glass with water, you will notice that the bubbles typically dissipate in less than one minute.
  • As is standard practice, water supplied to our customers meets or exceeds all regulatory requirements established by the State Water Resources Control Board (SWRCB) and the Environmental Protection Agency (EPA)

Benefits of Conjunctive Use

  • Conjunctive use improves the availability and reliability of water supplies despite variable rainfall by using groundwater during drought or peak use periods and storing groundwater during wet periods.
  • Conjunctive use practices are beneficial for our environment and eco systems. In drier years when river conditions are stressful to fish, conjunctive use allows more surface water to remain in the river. This increases spawning and rearing habitat availability while also providing cold water for increased fish survival.
  • Additional surface water adds flexibility to manage in-stream flows in the lower American River for recreation, esthetics, and protection of other aquatic resources.

Benefits of Water Sales

  • The sale of surface water generates additional revenue for the District’s financial planning activities. This additional resource will help in funding water supply projects such as additional groundwater supply wells.
  • Water sales and transfers also help offset revenue lost due to drought reduction and possible water right curtailments.
  • This adds an additional resource for the District’s long term financial planning for a stabilized rate structure to balance drought revenue reductions.

Resources