Operation and Rules of the Lagoon


PRIVATE PROPERTY: The Belvedere lagoon is privately owned and maintained by the Belvedere Lagoon Property Owners Association (BLPOA) and its use is restricted to BLPOA members, their guests and tenants, and Belvedere Sailing Society (BSS) members. No classes or organized group activities are permitted unless approved in advance by the BLPOA.

USES: Permitted uses include swimming, sailing and windsurfing, and the use of manually-powered craft such as rowboats, canoes, paddleboats, and paddle boards. Multi-hulled sailboats and power driven craft of any type ARE NOT permitted on the lagoon because they have proven to be a safety hazard, especially for swimmers. (BLPOA maintenance operations are an exception). PLEASE RESPECT YOUR NEIGHBORS. The maximum length allowed for a sailboat on the lagoon is 15 feet. Boats and floatation devices are to be stored on docks and NOT anchored on BLPOA property. Fishing is permitted (Fish and Game license and regulations apply), however unattended lines are not allowed, and fishing is prohibited when water quality maintenance is underway. We recommend that residents consult the BLPOA website, www.belvederelagoon.org, for water quality alerts before swimming. Contact with lagoon water should be avoided for at least 72 hours after a rain.


  • BLPOA/BSS members and their guests/tenants are responsible for their own safety. There are no lifeguards on duty on the lagoon and a close watch should be maintained on non-swimmers, especially children. Small children using the lagoon's island should be accompanied by an adult. DO NOT swim near or climb on the tide gates located at San Rafael Ave. between Edgewater and Windward Roads. This can be particularly dangerous when the gates are open.
  • Swimmers always have the right-of-way over all watercraft. However, swimmers are encouraged to watch for boats on the lagoon and to avoid swimming near buoys or the start/finish line during sailboat races. Swimmers are encouraged to wear bright colored caps for better detection.
  • Boats should be operated in a safe manner at all times. Manually powered craft have the right-of-way over sailboats and sailboards. Sailboats should follow the basic "starboard over port tack" and "leeward over windward" right-of-way rules when encountering another sailboat or sailboard. California State Law AB 2538 requires boat passengers 11 years of age or younger and personal watercraft users to wear life jackets.

CONDUCT: Persons using the lagoon should conduct themselves with consideration for others. Sound travels more easily over water and therefore loud noise or music on the water, especially at night, can be annoying to others. Flood lights beamed at the water can also reflect into neighbors' homes. In all activities on or near the lagoon, please practice a "good neighbor" policy.

BUOYS: Only BSS buoys are allowed on the lagoon. They mark courses for the BSS sailboat races. Please do not move or tie boats to them.

ISLAND: The lagoon's island is for day use only. Dogs, fires or camping are not permitted. Please stay off the rock retaining wall that surrounds the island.


  • The BLPOA has water quality tests performed monthly (twice per month during the summer). If required, efforts will be made by flushing and debris removal to maintain water quality. Lagoon pollution can be at its highest level immediately following a storm when pollutants are washed into the lagoon from storm drains, therefore use of the lagoon and fishing at these times is discouraged and contact with lagoon water should be avoided for at least 72 hours after a rain. If you are a BLPOA member, please email us at info@belvederelagoon.org to make sure we have your current email address, so we can send you notices regarding this, if necessary.
  • City Ordinance #177 prohibits disposal of any pollutant into street drains. These drains empty directly into the lagoon. Debris should not be allowed to fall or be disposed of in the lagoon. Homeowners are responsible for informing their gardeners, painters, cleaning people, car detailers, and contractors of these regulations.
  • Fertilizer, and other phosphate-containing materials such as car wash soap, can impact lagoon water quality and are nutrients for algae and widgeon grass. LAGOON RESIDENTS SHOULD LIMIT THEIR USE OF THESE PRODUCTS near the lagoon and the drains that empty into the lagoon.


  • The BLPOA performs regularly scheduled maintenance on the lagoon. From March through September, chemicals are periodically used by BLPOA maintenance staff to control outbreaks of algae or widgeon grass around the lagoon. Unless otherwise notified by the BLPOA, the use of these chemicals does not require any restriction on use of the lagoon following application.
  • Lagoon homeowners/tenants are responsible for maintaining their bulkhead and/or dock, including areas under the dock. Vegetation should not be allowed to grow into the lagoon water as this encourages algae growth.
  • When not in use, boats should be properly stored out of the lagoon water on the owner's property. During winter months, boats should be properly secured to the dock. Missing or found boats should be reported to the BLPOA office (415-435-0285), not the Belvedere police. Boats left unattended in the water over extended periods become an unsightly nuisance and may be removed by the BLPOA at the owner's expense. Boats left unclaimed at the BLPOA/BSS boatyard for more than 90 days will be sold or destroyed.

BOATHOUSE AND YARD: Located at 50 Lagoon Road, the boathouse/yard is owned by the BLPOA and is used for maintenance work, boat storage, and other authorized functions. The boat-dock area may be used by BLPOA and BSS members only for boat launching and removal. Small boats stored in the yard must be registered with the BLPOA. Boats, trailers, and equipment left at the boatyard/boathouse not registered with the BLPOA will be removed at owner's expense. Call 415.435.0285 for LAGOON LOST & FOUND.


  • Lagoon property owners/tenants are not permitted to fill, dig out, or build on BLPOA property, including any permanent or floating dock or structure. Construction on lagoon waters which is part of the homeowner's property is permitted provided the required building permit and survey, if required, are obtained. Homeowners contemplating work on their dock or lagoon bulkhead may request the lagoon water level to be lowered. This will only be permitted between November 1st and April 1st, subject to the weather and tide/water conditions in Richardson Bay, and to a water level and for a period of time at the discretion of the BLPOA. Contact the BLPOA at 415-435-0285 at least one week in advance to make arrangements.
  • Construction of docks, lagoon bulkheads, and other structures near the lagoon should take into consideration the seasonal water levels of the lagoon as provided under Water Level Control. Bulkheads should be designed and maintained to allow for the fluctuation in lagoon water levels and to allow for periodic dredging on the lagoon side of the bulkhead to maintain water depth.
  • Homeowners are responsible for maintaining the integrity of their lagoon bulkhead and the proper elevation of their property to prevent possible property flooding or "slumping" into the lagoon. A diagram showing recommended bulkhead design is available upon request.


  • The BLPOA controls the water level in the lagoon through three manually operated gates at culverts under San Rafael Avenue that connect the lagoon to Richardson Bay. These gates allow salt water intake into the lagoon during high tides, and water discharge from the lagoon during low tides. Water levels in the lagoon are also affected by storm water runoff that enters the lagoon through Tiburon's and Belvedere's storm water drainage systems. Lagoon water level is adjusted as necessary to establish an appropriate balance between recreational use of the lagoon and flood control requirements.
  • During the period from April 1st to October 1st, the summer operating level (SOL) for the lagoon is approximately 3.5 feet above Mean Lower Low Water (MLLW is the basis for tide tables). During this period, the emphasis is on recreational uses of the lagoon and the water level is left constant except during periods of flushing for water quality control. During the rest of the year, the water level is lower to provide for rainfall/storm water storage. The target winter operating level (WOL) for the lagoon is approximately 2.2 feet MLLW (15 inches below SOL). The water level may be temporarily adjusted below the SOL/WOL without notice by the Lagoon Operating Manager due to weather and tide conditions, or for maintenance.

INQUIRES OR QUESTIONS ABOUT THE LAGOON OR BLPOA: For any questions or inquiries about lagoon operations or maintenance, leave a message at 415-435-0285, or write to BLPOA, P.O. Box 465, Belvedere, CA 94920.


Lagoon Safety Tip:

Manually powered craft have the right-of-way over sailboats and sailboards. Sailboats should follow the basic "starboard over port tack" and "leeward over windward" right-of-way rules when encountering another sailboat or sailboard.


Lagoon Safety Tip:

Manually powered craft have the right-of-way over sailboats and sailboards. Sailboats should follow the basic "starboard over port tack" and "leeward over windward" right-of-way rules when encountering another sailboat or sailboard.