Katy Flood Risk Resources: FEMA Maps, Harris and Fort Bend

A few local basics

The city of Katy lies in parts of Harris, Fort Bend and Waller counties, so your address may fall under different local agencies depending on the county. Your tax bill, your city or municipal utility district, and your county's maps can help you figure out which applies.

Some background that helps when reading flood information for this area:

• The Addicks and Barker reservoirs are U.S. Army Corps of Engineers flood control reservoirs in west Harris County. They were built in the 1940s and are dry most of the time.
• During Hurricane Harvey in August 2017, heavy rain caused widespread flooding across the Houston region, and both reservoirs held large volumes of water.
• Buffalo Bayou begins in the Katy area and flows east through Houston. Bear Creek and South Mayde Creek drain parts of the area toward Addicks.
• The Brazos River runs west and south of the area. Richmond and Fulshear sit on the Brazos side of the region.

Which watershed you are in tells you which creek or river matters most for your street. It is a useful first question, and the tools below can help answer it.

Step 1: Look up your address on a FEMA flood map

FEMA's Flood Map Service Center is the official public place to find flood maps. You type in an address and the site shows the flood map panel for that location, along with a zone designation.

1. Go to the FEMA Flood Map Service Center at msc.fema.gov.
2. Use the address search.
3. Open the map for your location and note the flood zone label.
4. Save or print the map panel, and write down the date on it.

FEMA's FloodSmart site, the public face of the National Flood Insurance Program, also has pages for finding your flood risk and your flood zone. The Ready.gov flood page points readers to the same Map Service Center, and adds a caution worth remembering: flooding does not follow the lines on a map.

What a flood zone designation means, in general

FloodSmart describes flood zones as labels on a community's flood map that show a level of risk, from higher to lower. In general terms:

Three cautions:

• A map is a snapshot, drawn from the data available when it was made. Development, drainage work and heavy rain can change how water behaves.
• A lower-risk label does not mean a home cannot flood. Houses outside mapped high-risk areas do flood.
• Lenders, insurers and local permit offices each use maps in their own ways. Your agent can tell you what applies to your policy.

Harris County Flood Control District (HCFCD) makes the same point in its own words. Its flooding page says everyone lives in a flood zone, and that you do not need to live near water to be flooded.

Step 2: Use local tools in Harris County

The Harris County Flood Control District, created by the Texas Legislature in 1937, runs several public resources.

• Floodplain lookup. HCFCD's watershed pages, such as the one for the Addicks Reservoir watershed, include a "Check my Floodplain" link. That page lists Bear Creek, Horsepen Creek, Langham Creek and South Mayde Creek among its primary streams. HCFCD's site also links to a list of interactive mapping tools.
• Flood Warning System. The Harris County Flood Warning System, at harriscountyfws.org, shows rainfall, channel status and water levels on a map. It is meant for watching conditions as a storm develops. The site carries a disclaimer, so treat it as one input and follow official alerts.
• Flood education and history pages. HCFCD publishes the history of major floods in the county, including Harvey, and explains how drainage works.
• Notifications. HCFCD's site has a link to sign up for flood warning notifications.

Do not wait for a storm to try these. Open each one on a dry day, find your watershed, and bookmark the pages on your phone.

Step 3: Fort Bend County resources

If your home is in Fort Bend County, which includes Richmond and Fulshear, start with Fort Bend County's Drainage District page. The district's stated mission is to maintain drainage channels where it has easements, and it also checks drainage plans for new developments. The county posts criteria documents, including minimum slab elevation criteria for new construction. These are mainly for builders and engineers, but they show that elevation rules exist at the county level.

Fort Bend County's Drainage District and engineering offices are sensible places to ask who handles floodplain questions for your address. Call or write to the county office rather than guess. If you live inside a city or a municipal utility district, ask them too, because local rules and local drainage maintenance can differ from the county's.

If your address is in Waller County, such as Brookshire, look for that county's floodplain administrator and ask what maps they use.

Elevation certificates, in general

An elevation certificate is a document that shows how high a building sits compared with expected flood levels. FloodSmart says it includes details like the building's location, its characteristics and its first floor height. Insurers can use it to judge flood risk, and it may affect what you pay for flood insurance.

Your home may already have one on file. FloodSmart suggests contacting your local floodplain manager, whose contact details are often on city or county sites. A licensed surveyor typically prepares new ones. Keep a copy with your insurance papers. It is a technical document, so ask your insurance agent to explain what it means for your policy.

Before a storm

This is a simple checklist, built on what public agencies publish.

1. Know your zone and your watershed. Do Step 1 and Step 2 now.
2. Check your coverage. Standard homeowners policies typically exclude flood, and a new flood policy generally has a waiting period. Our guide on flood vs water damage insurance covers the basics.
3. Photograph your home and belongings now. Date-stamped photos of every room make a later claim easier.
4. Gather papers. Keep your policies, ID, mortgage information and agent contact in a waterproof bag or a secure cloud folder.
5. Make a plan. Pick a route out, a place to go and a person to call. Follow evacuation orders when officials give them.
6. Move valuables up. Put important items on high shelves or upper floors.
7. Know your shutoffs. Learn where the main water valve and the electrical panel are.
8. Sign up for alerts. Use the county notification tools mentioned above.

During a storm

Stay informed through official sources. Ready.gov's "Turn Around, Don't Drown" message states that six inches of moving water can knock you down, and one foot can sweep a vehicle away. Stay off flooded roads. If water is entering the home and you can reach higher ground, go there. In an emergency, call 911.

After a storm

1. Wait for the all-clear. Do not enter a flooded home with live power, and stay away from downed lines.
2. Treat floodwater as unsafe. It can carry sewage and chemicals. Wear boots and gloves if you must go in, and wash well afterward.
3. Photograph everything before moving or tossing anything.
4. Call your insurer and, if you have one, your flood insurance provider. Ask what they need from you.
5. Start drying promptly. The EPA says to dry water-damaged materials within 24 to 48 hours to limit mold.
6. Keep receipts for emergency repairs and temporary lodging.

Our guide to the first 24 to 48 hours after water damage goes through the early steps, and our page on flood water cleanup in Katy explains what pros typically do. If you work near the reservoirs and Buffalo Bayou, our page for the Energy Corridor area has local context.

When the water is out of the street and you need drying help, you can request help and we work to connect you with an independent local pro. Availability varies after big storms, so expect that it may take time.

Sources

• FEMA Flood Map Service Center: msc.fema.gov/portal/home
• FloodSmart (FEMA), flood zones: floodsmart.gov/flood-zones-and-maps/what-is-my-flood-zone
• FloodSmart (FEMA), elevation certificates: floodsmart.gov/get-insured/elevation-certificates
• Ready.gov, floods: ready.gov/floods
• Harris County Flood Control District, flooding and floodplains: hcfcd.org/About/Flooding-and-Floodplains
• Harris County Flood Control District, Addicks Reservoir watershed: hcfcd.org/Activity/Projects/Addicks-Reservoir
• Harris County Flood Warning System: harriscountyfws.org
• Fort Bend County Drainage District: fortbendcountytx.gov Drainage District page
• U.S. Environmental Protection Agency, mold: epa.gov/mold