People moving to the Katy area are often concerned about Katy flood zones. The good news is that, for the most part and with a few exceptions, most Katy neighborhoods are located out of Special Flood Areas. There are a few areas that are in 500-year Floodplain (yellow zone) and a few more that are near creeks, bayous, and low-lying areas that put them in the 100-year Floodway (purple).
Beware of new construction neighborhoods that are located in 100-year and 500-year flood zones! If you are buying a home, get my report for Katy flood maps.
To understand the flood lingo, a home in a 100-year flood zone has a 1 percent chance of flooding every year. If you are located in the 500-year flood zone, that likelihood is reduced to .2% every year. But keep in mind that natural disasters rarely follow the rules of probability to the letter. Instead of thinking of this as a fast and hard rule, it is simply meant to be a guideline for builders, homeowners, and community planners.

Source: https://www.proplogix.com/blog/how-elevation-certificates-help-determine-your-property-flood-risk
I’m not a flood expert, weather expert, engineer, surveyor, etc…I’ve just lived on the Texas Gulf Coast for over 40 years and experienced many floods, hurricanes and tropical storms. Here’s my opinion based on what I have experienced…
Pretty much all areas of the United States (and the world) have to deal with natural disasters. In California it’s earthquakes, mudslides, and wild fires. In the Midwest it’s tornadoes. In the Northeast it’s winter storms and blizzards. Many parts of the country deal with flooding…especially near rivers. Other parts deal with severe droughts. The fact is, you can’t completely avoid natural disasters anywhere…so you need to minimize your risk and prepare for them as best you can.
If you want to live anywhere on the Gulf Coast (Texas, Louisiana, Mississippi, Alabama, Florida) or anywhere in the Houston region, then you will need to be prepared for hurricanes and flash flooding. One thing history has shown us regarding flooding…history means nothing! Each time we experience a major flood, you will see many flooded home owners on the news saying something like, “We’ve lived here over 30 years and never flooded before.” Last year (2019) there was a major flash flood and the new thing we heard afterwards was, “We didn’t flood in Harvey, but we flooded this time.”
So just because a home has never flooded before, does NOT guarantee it will not flood in the future. It just means it has a lower risk for flooding. Likewise, just because a home flooded during Hurricane Harvey, does NOT mean it will ever flood again. That was a historical storm that, most experts believe, is unlikely to occur in Katy again in our lifetime.
So, if you are buying a home in most parts of Katy Texas that do not back to a natural water source, then your risk for your home flooding is relatively low, especially compared to the rest of the Houston area. However, I still recommend you buy flood insurance! Trust me, it’s worth your “peace of mind” when hurricane season rolls around.
NOTE: In my definition of “flooding” I am referring to the interior of your home being infiltrated with flood/surface water. This does not refer to typical street flooding, since our streets are part of the designed drainage system in our area.
Flood Facts for Houston Area
Risk
- Floods are the #1 natural disaster in the United States.
- Just an inch of water can cause costly damage (est $25,000) to property. As little as six inches of moving water can knock you off your feet or move your car.
- Everyone is at risk.
- Most homeowners insurance doesn’t cover flood damage.
- More than 50 percent of properties in high-risk areas remain unprotected by flood insurance; all properties in high-risk areas need to be protected with flood insurance.
- Between 20 and 25 percent of all flood insurance claims are filed in low-to moderate-risk areas.
- New construction can increase flood risk, especially if it changes natural runoff paths.
- More than 5 million Americans are protected with flood insurance but millions more are unaware of their personal risk for property damage or options for protection.
- For building in high flood risk areas, there is a 26 percent chance of experiencing a flood during the life of a 30-year mortgage, compared to a nine percent chance of experiencing a fire.
Impact
- Flood losses in the United States averaged $2.4 billion per year for the last decade.
- The National Flood Insurance Program (NFIP) has paid nearly $16 billion in flood insurance claims to policyholders during the 2005 hurricane season (as of August 31, 2006.)
- Federal disaster assistance is usually a loan that must be paid back with interest and is only available when a disaster has been federally declared.
- In the last 52 years, nearly 1,000 flood events have been designated as federally declared disasters.
- Nearly 75 percent of all federally declared disasters over the past five years involved flooding.
Source: https://www.eng.hctx.net/Consultants/Floodplain-Management/Floodplain-Information#FloodFacts
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What Katy Areas Flooded After Hurricane Harvey?
During Hurricane Harvey, two unprecedented things occurred that caused a few homes in Katy to flood (less than 8 percent, and that’s including businesses and retail establishments). The areas around the Addicks and Barker Reservoirs had the most severe issues, but some flooding occurred around natural bayous, creeks, and other low-lying areas.
Hurricane Harvey dropped a record-breaking amount of rain in the Houston region…over 50 inches (“only” 31 inches in Katy). The amount of rain that fell cause the Addicks-Barker Reservoirs to overfill.

Source: http://www.businessinsider.com/hurricane-harvey-2017-rainfall-map-2017-8
While Katy flood zones are typically rated as 100-year or 500-year, Hurricane Harvey is being described as a an unprecedented, 1,000 year or even 3,000 year event (read more)! This means that homes that flooded during that once-in-a-life time weather event may never flood again.

Source: https://en.wikipedia.org/wiki/List_of_wettest_tropical_cyclones_in_the_United_States


Source: https://www.hcfcd.org
What to Watch for When Buying a Home
Less than 8 percent of Katy homes and businesses (approximately 7,209) were flooded during Hurricane Harvey…so don’t let what you see on TV give you the wrong impression…most of the homes in Katy TX do not flood on a regular basis and did not flood even during this HISTORIC hurricane. The water got high and some of the roads were flooded for a few days (mostly around Fry Rd, east of Grand Parkway), but this was an unprecedented weather event which may never occur again.
With that in mind, I will say that it will be very important for home buyers to watch out for repaired homes and to make sure they have been repaired properly. The main thing that most people worry about is mold problems in homes that have flooded. Supposedly, once the homes have been properly dried out, then mold cannot grow. Mold requires moisture to grow. While mold spores are around us all the time, they will not grow and become a problem when the source of the moisture is eliminated. It’s usually hidden leaks and on-going moisture that allows mold to grow. (read more)
By now, homes that were repaired after Hurricane Harvey, should be properly dried out and restored. If there are any concerns of mold issues, it’s easy to have an environmental air analysis performed by an expert and determine if the home has a hidden problem with high levels of mold spores. If it does, then move on to another home. If it doesn’t, then you get an updated home in a beautiful area of Katy (where the homes tend to be older and outdated).

“I am highly allergic to mold and I always do an air analysis when I buy a home.
I paid for these tests on the last three homes I purchased, even though none
of them had ever flooded.” –Sheila Cox
The Texas Legislature passed a law, effective September 1, 2019, that now requires home sellers to fully disclose flood zones and flood history for homes. Section 5 of the Sellers Disclosure now looks like this:

So this will be information you will receive when you buy a home in Texas.
But beware of investors who have never lived in the home and can, therefore, avoiding reporting these issues. This is why you may want to avoid some investment properties. If a Seller company wants you to sign away your legal rights regarding Deceptive Trade Practices and their disclosure responsibilities (such as Zillow or OpenDoor), then BUYER BEWARE. (“Buyer Beware” is “code” for “don’t buy it!”)
> View a current list of Katy Homes for Sale in Low-Risk Flood Zones
How to Avoid Buying a Home in a High-Risk Flood Zone
If you want to watch out for homes in high-risk flood areas (and you should!), then hire a real estate agent who will watch out for you (Sheila Cox! 😀 ). Most home builders’ agents, in new construction neighborhoods, will NOT tell you that their neighborhood is in a 100-year flood plain. I have had to inform multiple clients about this over the years (and they were very grateful for me).
The year before Hurricane Harvey, I had a client who wanted to look at homes in a specific neighborhood, close to the Brazos river, that I knew had serious issues (although it hadn’t flooded yet). I informed her about the issues and prevented her from buying there. Guess what? Many homes in that neighborhood flooded during Harvey. It was a mess! My client was so grateful that I prevented her from buying in that neighborhood.
Unfortunately, the MLS does not provide a search field for “previous flooding” or flood zones. However, since I know the area so well, when I set up homes searches for my clients (request yours here), I can filter out the areas that I know are located in higher-risk flood areas. It’s not perfect, but it’s a good way to avoid risky areas. Then, when a client expresses interest in a specific home, I always double-check the flood map and the Seller’s Disclosure before I show the home. It’s really good to have someone looking out for your best interests!
About the New “Flood Factor” Website and Ratings
There’s a new information source on flooding that I am concerned about because it seems INACCURATE according to our actual real-world flood history and the FEMA flood maps. I highly recommend that you do NOT rely on the “Flood Factor” ratings in this area, or you may buy a risky home. Get more information in my report…
Get My Katy Flood Report
With Maps
(includes flood maps for new neighborhoods)

Flood Insurance Important for ALL Gulf Coast Areas
As a resident of the Gulf Coast, you should know that hundreds of homes in the Houston area that are not in high-risk flood zones and had never flooded before during any other flood or hurricane event, did flood during Harvey. So that means…you never know for sure and you had better carry Flood Insurance on your home at all times! In my opinion, a $400-500 flood insurance policy is worth the peace of mind you have from knowing you won’t be financially devastated if a storm sits on top of your neighborhood and drops 50 inches of rain! I don’t know of any areas in the country that can handle that much water…do you?
One of my biggest pet-peeves is hearing people in the Houston region say, “I don’t need flood insurance because my home has never flooded before.” Duh. Neither did approximately 85 percent of the homes that flooded during Hurricane Harvey! One thing I can guarantee you about flooding on the Gulf Coast…there are NO guarantees.
I live in a very low-risk flood zone X area and I have flood insurance!
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