
Tahoe Water Suppliers Association

The Tahoe Water Suppliers Association (TWSA) is a Lake Tahoe-based partnership of California and Nevada municipal water agencies, dedicated to providing clean and safe drinking water. Our water source is Lake Tahoe, allowing us to deliver some of the finest drinking water in the world.
TWSA Membership 
- Cave Rock Water System
- Edgewood Water Company
- Glenbrook Water Cooperative
- Incline Village General Improvement District
- Kingsbury General Improvement District
- North Tahoe Public Utility District
- Round Hill General Improvement District
- Skyland Water Company
- South Tahoe Public Utility District
- Tahoe City Public Utility District
- Zephyr Water Utility
- Lakeside Park Association
Mission Statement
The mission of the Tahoe Water Suppliers Association is to develop, implement and maintain an effective watershed control program in order to satisfy recommendations in watershed sanitary surveys, advocate for the protection of Lake Tahoe as a viable source of drinking water, and to satisfy additional state and federal requirements.
Board Meetings
TWSA Board Meetings are held quarterly. View meeting dates and agendas on the TWSA Board Meetings page.
Spill Reporting
To report a pollution spill or boat sinking, please contact the appropriate local agencies from the list below:
- U.S. Coast Guard, Lake Tahoe Station: 530-583-4433
- South Lake Tahoe Police Department: 530-542-6110
- Douglas County Sheriff: 775-782-9911
- El Dorado County Sheriff: 530-544-3464
- Placer County Sheriff: 530-581-6330
- Washoe County Sheriff: 775-832-4110
- Nevada Department of Environmental Protection; Bureau of Corrective Actions: 775-687-9485
- Outside NV: 888-331-6337
History of TWSA
The origins of the Tahoe Water Suppliers Association can be traced back to when Nevada members first began working together during the state adoption of the 1986 amendments to the Safe Drinking Water Act (SDWA) and the creation of the Surface Water Treatment Rul (SWTR). In 1992 the Nevada members completed the first of three sanitary surveys and control programs in addition to a pilot study to determine trihalomethane formation potential and ozone disinfection design criteria. As a result, the Nevada State Board of Health granted five suppliers “filtration exemptions,” while one supplier (Round Hill) implemented filtration. In 2002 the members formally became the Nevada Tahoe Water Suppliers Association (NTWSA). Three years later the group add its first California member and Nevada was dropped from the name, becoming officially the Tahoe Water Suppliers Association.
Since the first official association was formed in 2002, Incline Village General Improvement District has provided one of its staff members as the Executive Director, as well as additional support staff for TWSA operations. The TWSA is managed by a board with each supplier having one appointed board member. Members contribute monetarily each year to the operations of the TWSA relative to the size and usage of their systems.
For more information on the history of the TWSA please see the TWSA Program Milestones
Pollution Prevention Projects
Drink Tahoe Tap ® Campaigns 
Visit the Drink Tahoe Tap page for programs and resources.
Aquatic Invasive Species
TWSA is a stakeholder with multiple workgroups engaged in pollution prevention projects in the Tahoe Basin; spanning issues from aquatic invasive species (AIS) to microplastics pollution. TWSA first became involved in Aquatic Invasive Species (AIS) issues in 2007 as the Lake Tahoe Watercraft Inspection Program was first being established. Our work focused then, and continues to date, on public education of the threat posed to water quality and water supply by the potential introduction of AIS such as zebra or quagga mussels into Lake Tahoe. TWSA has maintained a presence in the working groups bringing innovative ideas and resources – promoting non-chemical methods (Ultra-violet light boat, bubble curtains/aeration, rubber bottom barriers, diver-assisted suction) for AIS management. TWSA serves as a group partner with the Nearshore Aquatic Invasive Weeds Working Group (NAIIWG) since 2011, and most recently, the Tahoe Keys Property Owners Association Control Methods Test.
- The Tahoe Keys has an active weeds management project – for details visit tahoekeysweeds.org
Microplastics in Drinking Water
The TWSA is on the forefront of policy and research regarding micro plastics contamination in drinking water. We are working with local researchers, the Tahoe Science Council, the California Water Board and others, as active participants in understanding this emerging threat – providing feedback and resources. The TWSA member have conducted intake monitoring and Tahoe Tap’s water quality remains excellent.
- Intake Monitoring: Lake Tahoe Micro-plastics Report (PDF)
- Microplastics in Lake Tahoe – Press Release 7/13/2023
Water Conservation
Water conservation is easy to do and may only require a small change in some of your daily habits. You can save money, energy, the environment, and of course, water! Visit the Water Conservation page for helpful tips and resources.
TWSA Resources and Reports
Documents
TWSA /USACE
Source Water Protection
- Nevada Tahoe Conservation District
- Nevada Division of Environmental Protection
- California Department of Public Health
- Best Management Practices (BMP)/Defensible Space for Homeowners (Vimeo video)
Contact Us
Phone: 775-832-1284
Mail: 1220 Sweetwater Rd, Incline Village NV 89451