Quick Answer: Bel Marin Keys owners pay two district parcel taxes that keep the lagoons working. Measure G funds the heavy infrastructure: the two boat locks, the levees and dredging. Measure D funds year-to-year waterway maintenance, including weed control. As of October 2026, lock construction is planned to start September 1, 2027, the weed program is under way, and North Lagoon dredging is being studied with no published cost or schedule yet.
Key Takeaways:
- Measure G started at $1,800 per parcel in 2024-25 and rises 2.5% a year for 21 years. By my math that's about $1,891 this fiscal year.
- Measure D dates to 2001, was $773 per household in 2023, and rises 2% a year. That works out to about $820 this fiscal year.
- Work at the locks is only allowed between September 1 and January 31, which is why the district's planned construction start is September 1, 2027.
- A professional lake-management firm, LakeTech, now handles weed control and water-quality monitoring in the lagoons.
- The exact amounts for any home are printed on its property tax bill.
If you own on the water in Bel Marin Keys, two lines on your property tax bill pay for most of what makes that water usable. One covers the locks and the other big infrastructure. The other keeps the lagoons clean and navigable from season to season. Buyers who are new to the Keys often don't know what either one is, so here's what each tax funds and where the work stands this fall.
What are Measure G and Measure D in Bel Marin Keys?
They are the two parcel taxes that fund the waterways. Bel Marin Keys isn't run by a homeowners association. The Bel Marin Keys Community Services District, a public agency, maintains the lagoons, the two navigational locks, the levee and the parks, and these two voter-approved taxes pay for most of the water side of that job.
Tax | What it pays for | Where it started | My estimate for 2026-27 |
|---|---|---|---|
Measure G (2024) | Infrastructure, "including locks and levees, and dredging waterways" | $1,800 per parcel in 2024-25, rising 2.5% a year for 21 years | About $1,891 |
Measure D (2001) | Maintaining the community's marine facilities, including lagoon and weed management | $773 per household in 2023, rising 2% a year | About $820 |
Together that's roughly $2,700 a year. The estimates are my own arithmetic from the starting figures the district publishes on its Measure G and Measure D pages. They aren't the county's certified charges, so use the tax bill for the real number.
When do the Bel Marin Keys lock repairs start?
The district's planned construction start is September 1, 2027. The project covers repairs and upgrades to the North and South locks and the North Flood Gate, according to the district's summer 2026 newsletter.
The schedule is set by permits and the calendar, not by money. Here's where things stand:
- State permits are done. The newsletter reports approvals from the Regional Water Quality Control Board and the California Department of Fish and Wildlife.
- The federal permit is the last big one. July board minutes show the district expecting the U.S. Army Corps of Engineers permit around the end of September. I haven't seen the district confirm that it has been issued.
- A county building permit comes next.
- The work window is short. Environmental rules limit work at the locks and seawalls to September 1 through January 31 each year.
In the meantime the fund keeps building. July committee minutes show about $2.2 million in the Measure G account. The district has also said it will choose its contractor on qualifications for this kind of marine work, not on low bid alone, and new stop logs for the North Lock were fabricated this summer.
What is the district doing about weeds in the lagoons?
It brought in a professional firm this year. LakeTech now manages the lagoons for the district, and the district manager's latest update lists what that includes: harvesting widgeon grass in the North Lagoon, applying a blue food-grade dye that slows grass growth, monitoring water quality and mapping the aeration systems.
The Measure D committee approved up to $100,000 a year for dye treatment in April, to be used only if needed. A North Lagoon flushing is scheduled for October 8 and 9. This is the part of the tax you can see from the dock, and it's ongoing maintenance by design.
Is the North Lagoon going to be dredged?
It's on the district's list, and it's early. June board minutes list a North Lagoon dredge as a future agenda item. July minutes say a committee will start analyzing a full dredge after the district finishes its search for a Waterways Manager, and that the existing dredging permit needs to be validated for the disposal site and the volume. The district is recruiting for that manager position now.
The funding piece is already in place in one sense, because Measure G's ballot language covers dredging. What I haven't found in the district's published documents is a cost estimate or a schedule. When those appear, they'll come through the board's public meetings.
Where can you find the exact numbers for a Bel Marin Keys home?
On the tax bill and the district's website. Marin County lists voter-approved charges as their own line items on the property tax bill, so the Measure G and Measure D amounts for any address are easy to confirm. The district posts its agendas, minutes and quarterly Neighbor to Neighbor newsletter at bmkcsd.us, the board meets on the third Thursday of the month at 6:30 p.m., and the office number is 415-883-4222. This post is general information, not tax advice.
For a look at the lagoons, the docks and the streets behind all of this, here's my Bel Marin Keys driving tour:
More on the Keys: waterfront living, benefits and tradeoffs, buying a boater-friendly home, the flood insurance guide and Bel Marin Keys in winter.
Thinking about Bel Marin Keys? Whether you're buying on the lagoon or getting ready to sell, I'm glad to walk through the neighborhood, the tax bill and the market with you. If you already have a number from another agent, a second opinion on that valuation costs nothing.
Kyle Frazier, JD, CRS, CLHMS · Broker Associate, Compass · DRE# 01405738
[email protected] · 415-350-9440
Frequently Asked Questions
Is Bel Marin Keys an HOA?
No. Bel Marin Keys is served by the Bel Marin Keys Community Services District, a public special district, not a homeowners association. The district maintains the lagoons, the two navigational locks, the levee, parks and boat ramps. A few enclaves inside the Keys have their own smaller associations, so check the documents for the specific address.
How much is the Measure G tax in Bel Marin Keys?
Measure G started at $1,800 per taxable parcel in fiscal year 2024-25 and rises 2.5% a year for 21 years. Applying that increase twice gives about $1,891 for 2026-27. That figure is my estimate from the district's published starting rate. The exact charge for any home is printed on its Marin County property tax bill.
How much is the Measure D tax in Bel Marin Keys?
The district says Measure D passed in 2001, was $773 per household in 2023 and rises 2% each year. Three years of that increase puts it at about $820 for 2026-27, by my arithmetic. It pays for maintaining the community's marine facilities, which includes lagoon and weed management. Confirm the exact amount on the property tax bill.
When will the Bel Marin Keys locks be repaired?
The district's planned construction start is September 1, 2027. State permits are in hand, and the remaining steps are the federal Army Corps of Engineers permit and a Marin County building permit. Work at the locks and seawalls is limited to September 1 through January 31 each year, so the schedule moves in one-year steps.
Is the North Lagoon in Bel Marin Keys being dredged?
Not yet. District board minutes from summer 2026 show a North Lagoon dredge on the list of future items, with a committee set to analyze it after the district hires a Waterways Manager. Measure G's ballot language allows the tax to pay for dredging. The district hasn't published a cost estimate or a schedule that I've found.
Sources: Bel Marin Keys Community Services District: Measure G ballot language and full text; Measure G and Measure D committee pages; Neighbor to Neighbor newsletter, July 2026; board and committee minutes, April through July 2026; From the District Manager (updated October 5, 2026). Status as of October 6, 2026. Schedules can change, so confirm with the district before relying on any date.
