Marin Waterfront Homes: Docks, Flood Zones and Shoreline Permits
A waterfront home in Marin County comes with a second set of rules that inland houses don’t have: who regulates the shoreline, who owns the land under the dock, what the FEMA flood map says, and what local sea-level-rise plans expect. On San Francisco Bay, the Bay Conservation and Development Commission (BCDC) has permit authority over the water and a 100-foot shoreline band; on the Pacific side, the Coastal Act and Marin County’s Local Coastal Program apply instead. Getting those answers for a specific parcel is most of the diligence on a Belvedere, Tiburon, Sausalito or Stinson Beach waterfront purchase.
This guide is for buyers comparing bay and ocean frontage across Marin. It sorts the county’s waterfront into types, explains which agency controls docks, seawalls and additions, sets out what flood insurance does and doesn’t cover, and ends with a document list to request before you remove contingencies. Town-by-town detail lives on our Marin County real estate guide and the local pages linked below.
Five kinds of Marin waterfront
“Waterfront” covers very different properties here. The setting decides which agencies you’ll deal with and which questions come first.
| Setting | Examples | Main shoreline regulator | First questions |
|---|---|---|---|
| Open bay frontage | Belvedere Island, the Tiburon shoreline, Sausalito’s bayfront | BCDC, plus the city or town | Seawall condition, pier permits, wave exposure |
| Lagoon or keys community | Belvedere Lagoon, Bel Marin Keys, Seadrift Lagoon in Stinson Beach | The city or county, plus the lagoon’s association or district; BCDC or coastal-zone status depends on the parcel | Association rules and dues, dock standards, levee protection |
| Creek, canal and marsh edge | Corte Madera Creek, Santa Venetia along Gallinas Creek | BCDC on tidal stretches; local flood control zones | Flood zone, pumps and levees, tidal access |
| Floating homes | Waldo Point Harbor and Sausalito’s marinas | BCDC, the county or city, the marina | Berth agreement, float survey, title |
| Ocean and Tomales Bay | Stinson Beach, Bolinas, Muir Beach, Inverness, Dillon Beach | Marin County under its Local Coastal Program, with Coastal Commission appeals | Erosion, septic, coastal permits, rental rules |
Floating homes are a separate purchase, because you buy the structure and rent the berth; our guide to Sausalito floating homes covers that market. Lagoon living in northeast Marin has its own district and special tax, explained in our Bel Marin Keys guide.
Who regulates the shoreline: BCDC, the Coastal Act and the town
Marin has two shoreline regimes. The County of Marin’s sea-level-rise page puts it plainly: the Pacific coastline is “subject to a distinct regulatory framework under the California Coastal Act and the California Coastal Commission,” while the bay shoreline falls under BCDC.
On the bay: BCDC
Under the McAteer-Petris Act, BCDC’s jurisdiction covers areas of the Bay subject to tidal action, including tidelands, submerged lands and marshlands up to five feet above mean sea level. It also covers a shoreline band, the strip between the shoreline and “a line 100 feet landward of and parallel with that line.”
Some tidal creeks are included too. BCDC’s list of certain waterways names Corte Madera Creek (to the downstream end of its concrete channel) and the Petaluma River among them, and it expressly excludes the Larkspur and Greenbrae Boardwalks. For a Larkspur or Greenbrae house on the creek, check exactly where the property sits.
BCDC says “most projects and activities in San Francisco Bay and along its shoreline require a permit.” The commission itself votes on major permits, while staff review the others, and the agency notes that many projects need other approvals before it will issue one. A new pier, a rebuilt seawall, fill or a larger deck within the band can all raise the question.
On the ocean and Tomales Bay: the Local Coastal Program
West Marin’s coastal communities are governed by Marin County’s Local Coastal Program, a land use plan plus a coastal zoning code (Title 20), with appeals to the Coastal Commission in some cases. Our guide to buying coastal property in Sonoma and Marin explains coastal permits, exemptions and bluff rules in detail.
The city, town or county underneath
BCDC and the Coastal Act sit on top of ordinary local permits. Belvedere, Tiburon and Sausalito run their own building and planning departments; unincorporated waterfront such as Strawberry, Santa Venetia, Bel Marin Keys and West Marin goes through the county’s Community Development Agency. Confirm the jurisdiction on the parcel record before you plan anything.
Docks, piers and the land under the water
A private dock can involve three separate questions: who owns the submerged land it sits on, which agencies permitted it, and who maintains it.
- Ownership. In California, tidelands can be privately owned, held by the state, or granted by the Legislature to a local trustee. Your title officer can tell you which applies, and what public trust or other exceptions appear in the preliminary report.
- State lands. Where a private pier sits on state lands, Public Resources Code section 6503.5 says the State Lands Commission “shall charge rent” for it, based on local fair annual rental values. Two kinds of older leases are exempt: one in effect on July 1, 2011, for the rest of its term, and one whose application and fees reached the commission before March 31, 2011. A replacement lease must include fair annual rent. If the seller has a lease, ask for it, its expiry date and the current rent.
- Permits. Ask for the BCDC permit (or confirmation that none was needed), the local building permit and any Army Corps or other approvals on file for the dock, gangway, float and boat lift.
- Associations. In a lagoon community, the association or district may set dock standards and boating rules. Read them with the CC&Rs before you plan a boat or a lift.
A dock’s condition matters as much as its paperwork. Pilings, floats and gangways wear out, so ask a marine contractor to look at the structure during your inspection period.
Seawalls, bulkheads and levees
Much of Marin’s bay frontage is held in place by private seawalls and bulkheads, and some neighborhoods rely on public levees. Both are cost and permit questions for a buyer.
Private walls
Repairing or replacing a seawall on the bay can need BCDC approval as well as a local permit, so a wall near the end of its life is a project, not a weekend repair. Ask the seller for the wall’s age, design drawings, repair history and permits, and have an engineer assess it if it shows cracking, settlement or undermining.
On the ocean side, the Coastal Act allows seawalls, revetments and similar structures when “required to serve coastal-dependent uses” or to protect existing structures or public beaches in danger from erosion (Public Resources Code section 30235). New development is expected not to need protective devices that would substantially alter natural bluffs and cliffs (section 30253), which limits armoring as a plan for new homes on the coast.
Public levees and pumps
Some waterfront neighborhoods depend on infrastructure owned by others. Two examples:
- Tiburon and Strawberry: Marin County Flood Control Zone 4 was formed in 1957 “to alleviate chronic flooding in Bel Aire.” It covers 850 parcels in parts of Tiburon, Bel Aire and Strawberry Circle, with 8 pumps at 3 pump stations and 0.15 miles of levee. Our Tiburon guide covers the town’s other hazards.
- Belvedere: the two levee roads to Belvedere Island are being reinforced; our Belvedere guide tracks the city’s seawall and levee schedule and funding.
Ask the city or district whether any assessment, parcel tax or ballot measure is planned to pay for future levee work before you set your budget.
FEMA flood zones and flood insurance
Many bay- and ocean-front parcels in Marin touch a FEMA Special Flood Hazard Area. Two zone types matter most:
- Zone AE is part of the Special Flood Hazard Area, with a base flood elevation shown on the map.
- Zone VE is a coastal high hazard area, which FEMA describes as an area “subject to high velocity wave action from storms or seismic sources.” FEMA adds that special floodplain rules apply there, including a requirement that buildings be raised on piles or columns.
Belvedere’s flood page says most properties in the Belvedere Lagoon and West Shore Road neighborhoods are in a Special Flood Hazard Area, either AE or VE; it doesn’t say which streets are which, so look up the address on FEMA’s map. The city keeps elevation certificates for new building projects in the flood zone, which you can ask to see at City Hall.
What flood insurance covers
Homeowners policies don’t cover flood. National Flood Insurance Program policies offer up to $250,000 for the building and up to $100,000 for contents, according to FEMA, and a new policy generally takes 30 days to take effect, though federal law (42 U.S.C. 4013(c)) waives that wait for a first policy bought in connection with a new or increased loan. A Marin waterfront house can easily be worth more than the federal building limit, so ask an insurance broker about private flood or excess flood coverage above it.
Get quotes early in escrow, with an elevation certificate if one exists, because the premium can change what a house costs to own. Our North Bay flood zone guide explains the maps, and our post on insuring a high-value California home covers the rest of the insurance picture.
What the disclosure report shows, and doesn’t
California’s Natural Hazard Disclosure Statement must say whether a property is in “a special flood hazard area (any type Zone ‘A’ or ‘V’)” or a dam inundation area (Civil Code section 1103.2). The statutory form doesn’t mention tsunami or sea-level rise, so look those up yourself. Our guide to the natural hazard disclosure report explains what a commercial report adds.
Sea-level rise planning on the bay and the coast
Marin’s sea-level-rise work is planning and coordination, not a single rule that applies to your lot. Still, it shows where the county and towns expect trouble.
The bay shoreline (BayWAVE)
The county’s 2017 Marin Shoreline Sea Level Rise Vulnerability Assessment, known as BayWAVE, covered the bay shoreline from Sausalito to Novato using the USGS CoSMoS model. It tested six scenarios:
| Timeframe | Sea-level rise | Sea-level rise plus a 100-year storm |
|---|---|---|
| Near term (about 2030) | 10 inches | 46 inches |
| Mid term (about 2050) | 20 inches | 56 inches |
| Long term (about 2100) | 60 inches | 96 inches |
The assessment’s community profiles show which streets and assets are exposed. Read the one for the shoreline you’re considering.
The ocean coast (C-SMART) and current work
On the Pacific side, the county’s earlier Collaborative Sea Level Rise Marin Adaptation Response Team (C-SMART) studied West Marin, including Stinson Beach; our Stinson Beach guide summarizes what it found there. As of October 2026, the county’s sea-level-rise page lists C-SMART among past efforts. It describes a governance study commissioned in 2024, with a Board staff report dated July 14, 2026, on how local agencies could work together on adaptation.
For a buyer, the practical step is to ask the town or the county planner whether any adaptation project, assessment district or new shoreline standard is proposed for the street.
Documents to request before you remove contingencies
- Jurisdiction: the parcel record showing city or unincorporated county, and whether the lot is within BCDC’s shoreline band or the coastal zone.
- Flood: the FEMA zone and base flood elevation, any elevation certificate, the seller’s flood policy declarations page and claims history.
- Shoreline structures: permits, drawings and repair records for the seawall, bulkhead, dock, gangway and boat lift, plus any State Lands lease.
- Title: the preliminary report’s exceptions for tidelands, public trust or access easements, and any recorded BCDC permit conditions.
- Association or district: CC&Rs, dock and boating rules, dues and any special tax on the bill.
- Local reports: the town’s resale report where one is required, and sewer lateral or septic records.
- Insurance: written flood and homeowners quotes for your own policy, not the seller’s.
Diamond may refer you to partners we work with; you’re free to choose any provider.
Selling a waterfront home in Marin
Waterfront buyers ask the same questions in every escrow, so put the answers in the listing file before the first showing: flood zone and elevation certificate, the flood policy, seawall and dock permits and age, any State Lands lease, and association documents. Missing permits for a pier or a wall surface late and slow escrows down.
Belvedere and Tiburon each require a resale report before a sale, and other Marin towns have their own point-of-sale rules; our Marin County selling requirements page lists them. Pricing should come from comparable sales with the same kind of frontage, since an open-bay lot, a lagoon lot and a creek lot are different products. Our Marin luxury homes guide covers how the top of the market trades.
Questions people ask
Do I need a BCDC permit to repair my dock or seawall?
Often, yes. BCDC says most projects in the Bay and along its shoreline need a permit, and its jurisdiction includes a 100-foot shoreline band. Ask BCDC staff before you plan work, and expect to need city or county permits as well.
What is the difference between flood Zone AE and Zone VE?
Both are FEMA high-risk zones. VE is a coastal high hazard area subject to high-velocity wave action, where FEMA’s rules require buildings to be raised on piles or columns; AE is a high-risk zone without that wave designation.
How much does federal flood insurance cover?
NFIP policies cover up to $250,000 for a home’s structure and up to $100,000 for contents. Owners of higher-value homes often look at private or excess flood coverage for the gap.
Do I own the water in front of my Marin waterfront home?
Not necessarily. Tidelands can be private, state-owned or granted to a local trustee. Your title report shows what you’re buying. Where a private pier sits on state lands, state law requires the State Lands Commission to charge rent, apart from a few older leases.
Does the natural hazard disclosure cover sea-level rise?
No. The statutory disclosure form covers FEMA flood zones, dam inundation, fire, earthquake fault and seismic hazard zones. Check sea-level-rise and tsunami maps separately.
Can I add a second story to a waterfront house in Belvedere or Tiburon?
Possibly, but flood-zone construction rules, local design review and, near the shoreline, BCDC review can all apply. Confirm feasibility with the city or town and an architect before you count on it.
Is Stinson Beach under BCDC?
No. Stinson Beach is on the Pacific coast, where Marin County’s Local Coastal Program and the Coastal Act govern development.
If you’re weighing bay or ocean frontage in Marin, we can pull the parcel’s permits, flood data and title exceptions with you before you write an offer. Start with our Marin buyer services, or contact us about a specific property.
This is general information, not legal or insurance advice; talk to a California real estate attorney, a licensed insurance broker and, for shoreline work, a coastal engineer about your property.
Sources & notes
- San Francisco Bay Conservation and Development Commission: Jurisdiction
- San Francisco Bay Conservation and Development Commission: Permits
- California Public Law: Public Resources Code section 6503.5 (rent for private recreational piers)
- California Public Law: Public Resources Code section 30235 (shoreline protection)
- California Public Law: Public Resources Code section 30253 (minimizing hazards)
- California Public Law: Civil Code section 1103.2 (Natural Hazard Disclosure Statement)
- FEMA: Glossary, coastal high hazard area
- FEMA: Fact sheet, flood insurance: what to know
- City of Belvedere: Flood zone resources
- Marin County Flood Control District: Flood Control Zone 4, Bel Aire
- Marin County Flood Control District: Marin Shoreline Sea Level Rise Vulnerability Assessment (BayWAVE)
- County of Marin: Sea-level rise (page updated October 13, 2026)
- County of Marin Planning: Local Coastal Program
Not covered here: dock-specific sections of the Belvedere, Tiburon and Sausalito municipal codes, the State Lands Commission’s application process, and current flood insurance premiums, none of which we verified for this page.
Last reviewed October 2026 by Matthew Martinez.
