Regional Water Supply

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In the Carson River Watershed, water for the river system is provided by the Sierra snowpack in Alpine County.  The headwaters from the snow pack flow from the East and West Fork of the Carson River, its two tributaries, which join to form the main stem of the Carson River near Genoa, Nevada before continuing its journey to the terminus in the Carson Sink.

On its journey from the headwaters to the terminus, the Carson River flows through five major groundwater basins: Carson Valley, Eagle Valley, Dayton Valley, Churchill Valley, and Carson Desert (Churchill County Area). All the water in the Watershed, both surface and groundwater is fully allocated, so any new demands for water must come from existing sources.

One interesting project CWSD was involved in was updating the Marlette Water System. Learn about that project here.

CSWD is tasked by Nevada legislation to consider water supply & demands on a regional basis. Therefore, CWSD coordinates its work with water purveyors throughout the watershed to enhance their efforts to meet water demand for their users.

Identifying future water needs is a focus of CWSDs.  Therefore, CWSD funds studies and projects to understand future challenges to water supply.  CWSD also works with water purveyors as it considers municipal and industrial water users.

To help water purveyors meet their water demands, CWSD provides funds for regional pipeline and interties, and regional studies.  These funds and studies help water purveyors meet their water demands in the most economically viable way and in the most scientifically sound manner. CWSD also promotes water conservation throughout the watershed to avoid wasting water.

Preserving water and avoiding waste is critical in balancing the water resources among agricultural users, environmental needs, and municipal and domestic demands.

Applicable Water Laws

Nevada Water Law, California Water Law, and the Alpine Decree

Basic water laws governing surface and groundwater within the Carson River Watershed include Nevada Water Law, California Water Law, and the Alpine Decree.

Nevada Water Law

Nevada Water Law is based upon two fundamental theories of appropriation and beneficial use. This essentially means that water rights are based upon the state allowing individuals or entities the right to appropriate waters, both surface and groundwater, based on a priority system and availability. The priority is linked to the date of the first action taken to place water to a beneficial use. The earlier the priority date on a water right permit/certificate, the better its claim to utilize either surface or groundwater.
To learn more about Nevada Water Law, visit Nevada Division of Water Resources website at

California Water Law

California Water law is administered by the State Water Resources Control Board (Control Board).  Although all the surface water rights are included in the Alpine Decree, any water transfers, changes in use, changes in point of diversion, or purpose of use must be approved by the Control Board.
To learn more about California Water Law, visit website of California Water Resource Control Board at ttp://

Alpine Decree

The Alpine Decree (Decree) has adjudicated the use of all surface water associated with the Carson River. The Decree divides the river into 8 different segments, with each segment regulated within itself. Per the Decree, water will not be delivered to a senior priority in one segment against a junior priority in another segment.  For example, a senior priority in the Dayton segment will not receive water before a junior priority in the Carson Valley. This division of the river into segments and the management of the water as it moves downstream is one of the challenges in dealing with water management along the Carson Watershed. The ability to leave water in the river for transport downstream or upstream for use in a different segment is not unheard of; however, the amount and timing of when water can be used may be limited. Cooperation between surface water users will become more important as future growth strains available water resources. Developing agreements to move water through the river system could provide greater flexibility in meeting varying water demands as well as enhance flows in the river for habitat. Further research and development of a viable plan to manage water between segments of the Carson River is a significant task that will need to be evaluated and undertaken as part of an overall Watershed management system/plan.
Alpine Decree

Carson River Watershed Water Purveyors

Major Water Purveyors

Within the Watershed, there are several public water purveyors in the watershed. In addition to these, there are other water users and domestic wells.

Alpine County, California

Alpine County:  The majority of water use in the Carson River Watershed portion of Alpine County is from domestic wells. However, a small water system is operated in Markleeville by Markleeville Water Company.
The Washoe Tribe of Nevada & California operates a small water system in its Woodfords Community.

Douglas County, Nevada

  1. Gardnerville Ranchos GID:  Gardnerville Ranchos GID (GRGID) is located in the southern part of the Carson Valley.
  2. Gardnerville Water Company:  The Gardnerville Water Company provides water to the Town of Gardnerville within the central portion of the Carson Valley.
  3. Town of Minden:  The Town of Minden provides retail water to the Town of Minden, the Bently Science Park, and wholesale water to Douglas County, Indian Hills GID, and in 2014 to Carson City.
  4. Indian Hills GID  Indian Hills GID (IHGID) is located south of Carson City and primarily serves residential customers.
  5. Douglas County Utilities:  Douglas County Utilities manages multiple water systems within the Carson Valley as follows:
  • North Valley System: The North Valley System is primarily the Walmart commercial area and future planned development along the north boundary of the County between Carson City and Douglas County.
  • East Valley System: The Douglas County East Valley System encompasses the Johnson Lane area north of the Douglas County airport.
  • West Valley System: The Douglas County West Valley System encompasses Genoa, Walley’s Resort, and the developed areas along the Jack’s Valley Road golf courses.
  • Fairgrounds/Sunrise Estates: These two systems located in the southeast portion of the Carson Valley provide water for the county’s fairgrounds and a small residential development located north of the county fairgrounds.
  • Sheridan Acres/Jobs Peak: These two systems are located in the southwest portion of the Carson Valley and are adjacent to residential areas located off of Foothill Road Directly west of the Gardnerville Ranchos GID.

Carson City, Nevada

Carson City:  Carson City is the single largest water supplier within the Carson River Watershed with approximately 18,500 connections and serves a population of about 55,000.  In addition, Carson City has a robust water reuse program administered by its wastewater department.

Storey County, Nevada

Virginia City is served by the historic Marlette Water System, which also provides water to Carson City. Part of the Marlette system was built in the late 1870’s and is still being used today. Storey County maintains the Virginia City water system.

Lyon County, Nevada

  1. Lyon County Utilities:  Lyon County Utilities like Douglas County maintains a variety of systems spread along the Carson River corridor including Mound House, Dayton, and the Mark Twain Area.
  2. Stagecoach GID:  Stagecoach is a small GID located northeast of the Dayton area. The Stagecoach area along with Silver Springs has a large potential for growth with the completion of the USA Parkway project.
  3. Silver Springs Mutual Water Company:  Only a portion of the developed area around Silver Springs is served by the municipal water company. This area near Lahontan Reservoir has a large potential for growth with the USA Parkway completion.

Churchill County, Nevada

  1. Churchill County:   Churchill County manages a small water system located to the west of the City of Fallon.
  2. City of Fallon:   The City of Fallon provides water to only those areas annexed to the City and meeting their requirements for annexation. The City of Fallon currently treats water pumped from the Naval Air Station. This water is treated and then pumped back to the air station.
  3. Fallon NAS   The Naval Air Station located southeast of the City of Fallon has a separate water system, which provides water to the base and base housing. The Naval system serves a population of approximately 700 customers/users.
  4. Fallon Paiute Shoshone Tribe:   The Fallon Tribe has a sizable water system in the Carson Desert Valley Basin that serves an estimated 330 connections.

Other Water Users and Domestic Wells

Currently there are over 8,000 wells in the Watershed.  Obtaining actual numbers of domestic wells within each hydrographic basin will be helpful over the next 30 years to face challenges such as decreasing water quality (example: high nitrates from septic system) or declining ground water levels.   Additionally, there are many smaller water systems throughout the Watershed.  As they struggle to meet clean water standards, they are often driven to join municipal systems.