Renton Flood Zones: Checking a Home Near the Cedar River

Renton flood zones are narrower than most buyers expect. On FEMA’s current flood map, the high-risk zone along the lower Cedar River stays almost entirely inside the river channel, and of the 11,035 single-family lots we checked in six neighborhoods, four touch a high-risk zone at all. The more common label, by far, is the moderate-risk zone that covers most of North Renton.

At The Rache Team we have guided Renton buyers and sellers for more than 26 years, and flood questions come up on nearly every home near the river. So on October 7, 2026 we downloaded FEMA’s National Flood Hazard Layer for Renton and laid it over King County’s parcel boundaries for every single-family home in the neighborhoods we cover. This guide reports where Renton flood zones fall, street by street, and how to check any address yourself.

How Renton Flood Zones Are Mapped

The official source for Renton flood zones is FEMA’s Flood Insurance Rate Map. The panels that cover the city took effect on August 19, 2020, and the City of Renton adopted the matching flood study, by that date, in its critical areas code. The lower Cedar River, North Renton and The Landing are on panel 53033C0977G. You can view any panel at the FEMA Flood Map Service Center.

Four labels matter when you read Renton flood zones on the map:

• Zones AE and AH. These are Special Flood Hazard Areas, land with a 1% chance of flooding in any year. FEMA’s flood insurance program describes that as a 1 in 4 chance of flooding at least once over 30 years. Zone AH marks shallow flooding or ponding with a set flood elevation.
• Floodway. The channel and the land beside it that must stay open to carry flood water. Renton’s code prohibits new residential construction there except under narrow conditions.
• Shaded Zone X. The 0.2% annual chance flood area, often called the 500-year floodplain. FEMA calls it moderate risk and notes that such areas may have reduced their risk with levees or may see shallow flooding.
• Unshaded Zone X. The area of minimal flood hazard.

One note on our method. We counted lots, not buildings. A lot “touches” a zone when more than 1% of its area falls inside it, so a house can sit well clear of a zone that crosses its back fence.

Where Are Renton Flood Zones Along the Cedar River?

King County describes the lower 1.25 miles of the Cedar River through Renton as the only segment of the river fully lined by levees, built to reduce flood risk to downtown, the Boeing plant and Renton Municipal Airport. The FEMA map reflects that. From Interstate 405 to Lake Washington, the floodway and Zone AE follow the channel between the banks and reach very little private land.

The parcels that do touch the high-risk zone on this stretch are mostly public or commercial. The Renton Library at 100 Mill Ave S, which spans the river, sits in the floodway. So do edges of the Renton Community Center and Cedar River Park, the city’s parks maintenance yard on N 1st St and the east side of the airport. Two riverside apartment properties, on Maple Valley Hwy and on Burnett Ave S, have a strip of Zone AE along the bank. We found no single-family home in the high-risk zone between I-405 and the lake.

The levee is not a permanent fact, and it is worth knowing its recent history. The City of Renton reported in August 2026 that the Cedar River Left Bank Levee near the Boeing Bridge was damaged in a December 2025 flood. The city and the U.S. Army Corps of Engineers made repairs over two weekends that month, placing rock to protect the flood wall before this flood season.

North Renton: Renton Flood Zones on the Grid

North Renton is where the shaded Zone X matters. Of 360 single-family lots, 318 are in the 0.2% annual chance area, and 308 of those are entirely inside it. That covers nearly all of Wells Ave N, Pelly Ave N, Williams Ave N and Burnett Ave N. The 42 lots outside the shaded area are at the southeast corner of the grid, mostly on the 100 and 200 blocks of Meadow Ave N, Factory Ave N and Garden Ave N.

This is a different picture from the risk scores on listing sites. In our North Renton seller guide we cited a First Street rating that gave 74% of the neighborhood’s properties some risk of severe flooding over 30 years. That model and the FEMA map measure different things. First Street estimates future risk from rain, rivers and climate projections. FEMA’s map is the regulatory line that decides where flood insurance is mandatory. Both can be right: North Renton is low and flat, it is outside the high-risk zone, and almost all of it is inside the moderate one. Our North Renton neighborhood guide covers the rest of life on the grid.

The same shaded zone continues south across the river into the older blocks around S Tobin St, Logan Ave S and Williams Ave S, and it takes in several small condominium buildings on both sides.

The Landing and Southport

The two parts of the north end map differently. The Landing’s retail blocks along N 10th St and Park Ave N, and the apartment buildings on N 10th Pl, are in unshaded Zone X. At Southport, the Bristol apartment buildings, the office campus and most of the Hyatt Regency site are in the shaded Zone X. Gene Coulon Memorial Beach Park is almost entirely unshaded. Lake Washington itself is not mapped as a flood zone here, which is why the shoreline does not carry a high-risk band. See our Landing and Southport price guide for what sells there.

Renton Hill

Renton Hill rises directly above the river, and every one of its 229 single-family lots is in unshaded Zone X. The flood map is one of the clearest differences between the hill and the grid below it. It does not tell you how rain moves across a sloped lot, which is a drainage question for each property. The Renton Hill guide has more on the neighborhood.

Renton Flood Zones Away From the River

The largest high-risk area in Renton is not on the Cedar River. It is on the valley floor south and west of downtown, along Springbrook Creek and the old Black River channel.

Earlington and the Valley Floor

All 709 single-family lots in Earlington and the city’s West Hill are in unshaded Zone X. The neighborhood sits on the slope. Below it, Zone AE covers much of the office and industrial land along Lind Ave SW, Oakesdale Ave SW, Naches Ave SW and East Valley Rd, and Zone AH covers part of the Renton Village shopping center and other parcels on S Grady Way. Those are places Earlington residents shop and work, not places they live. Our Earlington neighborhood guide describes how the hill and the valley connect.

Talbot Hill: Four Lots on Talbot Rd S

Talbot Hill has the only single-family lots in our set that touch a high-risk zone. A Zone AH with a flood elevation of 19.5 feet covers the wetland between State Route 167 and Talbot Rd S. Four homes in the 2700 to 3200 blocks of Talbot Rd S have that zone on the low, back portion of the lot, covering from 3% to 36% of the lot. No Talbot Hill lot is half inside it. The other 1,266 lots are in unshaded Zone X. Read the Talbot Hill guide for the rest of the neighborhood.

Renton Highlands and Skyway-West Hill

Neither plateau has a mapped flood zone on a single-family lot we checked. That is 4,341 lots in the Renton Highlands and 4,126 in Skyway-West Hill, including the homes on the lake. Hills have their own water and soil questions, but Renton flood zones are not among them.

What Do Renton Flood Zones Mean When You Buy?

Renton flood zones change three practical things: insurance, what you can build, and what the seller tells you.

• Insurance is a cost to price in. In a high-risk zone, flood insurance is mandatory when the mortgage is government-backed, according to the National Flood Insurance Program. In the shaded Zone X it is optional. The program reports that 29% of its claims from 2014 through 2024 came from outside high-risk areas, so optional does not mean pointless. Ask an insurance agent for a quote on the specific address before you make an offer. A new policy normally takes effect 30 days after purchase, with an exception when it is bought with a new mortgage.
• Building rules follow the line. Renton regulates Special Flood Hazard Areas and floodways through its critical areas code. If part of a lot is in one, ask the city what that means for an addition, a garage or a detached unit before you count on building it.
• The seller disclosure asks about water. Washington’s seller disclosure form asks whether there are floodplains or critical areas on the property, whether there has been flooding, standing water or drainage trouble, and whether the basement has flooded or leaked. Read those answers closely on any home on the grid.

Renton flood zones are also not a history. A home in unshaded Zone X can have a wet basement from groundwater or a blocked drain, and a home in the shaded zone may never have seen water. The FEMA map tells you about river flooding. The seller, the neighbors and the property itself tell you the rest.

How to Check Renton Flood Zones for One Address

1. Search the address at FEMA. The Flood Map Service Center shows the panel and the zone. Zoom in until you can see where the line falls on the lot.
2. Note whether the zone touches the house or only the yard. That distinction drives most of what follows.
3. Look at the city’s map. The City of Renton’s COR Maps viewer shows parcels with the city’s own layers. For Skyway-West Hill, which is unincorporated, use King County’s iMap.
4. Ask for an elevation certificate. If one exists for the home, it records how high the home’s main floor sits against the flood elevation.
5. Get an insurance quote early. Do it before the offer, not after.
6. Read the river’s recent record. King County’s Cedar River watershed page tracks levee projects and flood damage along the river.

For a wider view of each area’s housing, our guides to Renton lot sizes by neighborhood and Renton home ages by neighborhood use the same 11,035 homes.