Buying a Waterfront Home in Discovery Bay: What to Check

Discovery Bay sits just east of Brentwood, and its waterfront homes sell on the view from the back patio. Buyers who call me about one usually start with the dock. The questions that change the monthly cost come later, and they live in a few different offices.

Before you buy on the water in Discovery Bay, check four things: the parcel's FEMA flood zone, the new Reclamation District 800 levee assessment that starts on fall 2026 tax bills, the water and sewer bill from the Community Services District, and the permit history on the dock and anything on the slope.

Discovery Bay at a glance

• Government: unincorporated. The Community Services District runs water, sewer, landscaping, and recreation; the County handles the rest
• Levees: maintained by Reclamation District 800
• New levee assessment: first appears on fall 2026 property tax bills
• Flood zone: set parcel by parcel on FEMA's map

Who runs what in Discovery Bay

There's no city hall. Discovery Bay isn't a city, so the work is split. The Town of Discovery Bay Community Services District handles water, sewer, landscaping, and recreation, and everything else goes to Contra Costa County.

Reclamation District 800 is the third player. It maintains the levees, manages water circulation in the lakes and bays, and reviews construction on and around levees and slopes.

That split matters when you want to change something. Building permits come from the County, and if the work touches a levee or slope, RD 800 has a say too. Many neighborhoods also have an HOA with architectural rules. Ask which one governs the address and get its rules in your disclosure packet. My HOA resale disclosure guide covers what that packet holds.

Is flood insurance required behind the levees?

It depends on the parcel, not the town. FEMA's map puts each lot in a zone. In the high-risk A and AE zones, flood insurance is mandatory if your mortgage is government-backed. In the moderate- and low-risk X zones, including areas FEMA shows as protected by a levee, it's recommended rather than required, though a lender can still ask for it.

On a waterfront lot, the line between those zones can run close to the back of the property, because the water itself is mapped as high risk.

Look up any address yourself on FEMA's Flood Map Service Center. Then start your homeowners insurance early. I walk through that in locking in insurance before you close.

A new levee assessment starts on the 2026-27 tax bill

Many listings won't mention this one yet. RD 800's board formed a new maintenance and capital assessment in late 2025, and it first shows up on fall 2026 property tax bills. It pays for levee repair, drainage, water quality, and dredging, and the board can raise it with inflation each year, up to a 4% cap.

Waterfront buyers should know the amount isn't the same for every home. It depends on the parcel: land use, lot and building size, and for homes with boat access, which bay access zone the lot sits in. Two homes on the same street can pay different amounts.

RD 800 posts an assessment calculator on its assessment page. Run the address before you write an offer, and check that the address is inside the district at all. If you close mid-year, my supplemental tax bill post covers how property tax timing works.

Water, sewer, and the dock

In Discovery Bay the water and sewer bill comes from the CSD, on a rate schedule that steps up each July. Ask the seller for a recent bill, and check the CSD's current rates rather than a number from a listing.

The dock and the slope behind the house deserve their own look. Before you remove your inspection contingency:

1. Ask for the permit history on the dock, the deck, and any rock or bulkhead work. An unpermitted structure becomes yours at closing.
2. Ask your inspector what's in scope. If the dock, pilings, and shoreline aren't covered, bring in someone who works on docks. My home inspector guide covers what to ask.
3. Call RD 800 before planning changes to anything on the slope behind the house.

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Looking at a house on the water in Discovery Bay? Send me the address. I'll pull its flood zone and run the RD 800 numbers with you before you write anything. Call or text (925) 200-0717.

This post is general information, not legal, tax, or insurance advice. Flood zones, assessments, utility rates, and permit rules change and apply parcel by parcel. Confirm the current facts for a specific property with Reclamation District 800, the Town of Discovery Bay CSD, Contra Costa County, and your own insurance agent or attorney.

Margie Lupo, Broker Associate, SRES® · eXp Realty of Northern California, Inc. · DRE #01193496 · Brokerage DRE #02188495 · Equal Housing Opportunity

Sources

• FloodSmart, What's my flood zone? — flood zones and when insurance is required
• Reclamation District 800, Assessment Info — the new assessment and calculator
• Town of Discovery Bay CSD — what the CSD handles