Tag Archive for: Daniel and Kathleen Moore

What Can Be Done to Reduce Flood Risk?

Flood-control experts have many tools in their tool chests to reduce flood risk. They include:

  • Widening channels to increase stormwater conveyance
  • Deepening channels to increase stormwater conveyance via dredging
  • Benching, i.e., reducing floodplain height to increase stormwater storage
  • Building retention and detention basins to create more storage and reduce flood peaks
  • Improving building codes to mandate higher home elevations
  • Requiring greater setbacks from rivers, streams and bayous
  • De-snagging to prevent log-jams from backing water up
  • Preserving wetlands, grasslands and forests to absorb and slow runoff, and to create recreational opportunities for nearby homeowners
  • Bio-swales and ditches to create more stormwater storage and positive drainage around homes
  • Buying out flood-prone homes and converting the property to recreational or flood-mitigation space.

I’m sure more techniques exist. But those represent the big categories.

Complex Decisions Involving Many Factors

No one tool works for all situations. And many of the tools that reduce flood risk fly in the face of other human values. They may conflict with other values beyond safety, that we hold dear. Consider, for instance, property rights, individual freedom, job formation, expanding the tax base, a desire to live near water, and risk-taking.

So how do professionals decide which tools to apply where and when?

Again, it depends on a number of factors. To name a few:

  • What are the benefits compared to the costs?
  • Does the cost of the cure exceed the cost of the damage?
  • What is the recurrence interval of flooding in a certain area?
  • Are you trying to fix a problem or prevent one?
  • Is the trouble spot pre- or post development?
  • How frequent and deep will likely flooding be?
  • Are changing conditions upstream contributing to increased flood heights?
  • How much damage will flooding cause?
  • Is State or Federal disaster-mitigation aid available?
  • Is Disaster Relief aid available?

Homeowner Inquiry Prompted Exploration

A homeowner reacted to one of my posts today. She lives in a low-lying area near FM1485 and the San Jacinto East Fork. It flooded badly on May2, 2024. She was certain that dredging and tree removal from the East Fork would help. But after investigating the area online, then from the ground and air, I wasn’t sure.

The normal river elevation in that area is 47.25 feet.

But on May 2, the river rose to 77.4 feet – 17 feet above the top of the river banks and 30 feet above normal!

Jeff Lindner, Harris County Meteorologist, had this to say about the May flood. “Since 1994, this was the second highest crest of the river at FM 1485. It exceeded Tropical Storm Imelda by 4.0 ft and the October 1994 flood by 1.0 ft.”

Lindner continued, “The flood of record remains Harvey which was 4.0 ft higher than the May 2024 event. The river exceeded the .2% (500-yr) exceedance probability elevation at the FM 1485 bridge by 1.5 ft. The table below shows the top five highest peaks on the East Fork of the San Jacinto River since 1994 at that location.”  

Date Peak Elevation 
  • 8/27/17 (Harvey)            81.2 
  • 5/2/24                              77.4 
  • 10/18/94                          76.2 
  • 9/19/19 (Imelda)            72.8 
  • 11/14/1998                      71.6 

HCFCD calculates the elevation of a 100-year flood is 70.6 feet.

So…

Residents in this neighborhood experienced five 100-year-or-greater floods in 20 years. That’s one every four years. Is the risk 1% or 25% per year?

See the FEMA floodplain map below for the area in question.

It shows you how difficult flood prediction can be. It also shows you why even nature lovers should give water in Texas a wide berth unless they are prepared to lose everything. The May flood wasn’t even related to a tropical event!

u
Yellow/green diagonal line is the Harris/Montgomery County line. Image shows neighborhood S of FM1485 near East Fork. Crosshatch=floodway, Aqua=100-year and Tan=500 year floodplain.

Unfortunately, most of the homes in this neighborhood didn’t look like people could afford to lose everything. And I saw several that had been totally obliterated along with two roads that washed out.

I’m not sure what this was. But it was the only structure semi-standing for blocks around.

Professionals Say Buyouts Best Option In This Case, But…

In an area like this, flood-mitigation professionals have few good options. Given the depth of flooding, three professionals told me that intervention would have to be on a massive and costly scale to make a difference. As a result, each suggested buyouts as the best, most cost-effective alternative in this area.

Shortly after the May event, I interviewed a young couple named Daniel and Kathleen Moore. They lived on some of the highest land in the subdivision, but had flooded three times in the seven years that they owned their home (Harvey, Imelda, and May 2024).

They were hoping for a buyout. I called again today to see if they succeeded, but they were selling their property and moving out of state with their new baby. Why?

While Daniel was restoring the home, someone burned it to the ground on July 28th. Nothing stands there now but a charred chimney.

This was a heartbreaking story that deeply affected me personally. I once lived in a home near a creek that flooded frequently when I had two young babies.

While buyouts may sometimes be the most cost-effective option, they are not easy, according to a County Emergency Management Director that I interviewed. Counties must apply for FEMA buyout money and then it can take years to evaluate and rank all the applications and distribute the money.

Forest Cove buyouts took five years after Harvey to complete.

Ironically, the fact that the Moore’s were in a 500-year floodplain may have hurt their buyout chances. FEMA likes money to go to homes that are insured but which flood frequently.

So What About Dredging and Tree Removal?

The Moore’s lived in Montgomery County. But the other family that contacted me lived on the Harris side of the county line in the same neighborhood.

Typical scene in East Fork south of FM1485
Area has trees down everywhere.

Experts I talked to suggested dredging wouldn’t make an appreciable difference given the narrow width of the river channel and the height of flooding. Plus, it could undermine more trees along the heavily wooded banks.

Removing trees that have already fallen, they say, is a good idea. They could float downstream, form log dams that flood other homes, and/or harm boaters in Lake Houston. But who is responsible for removing them?

I asked Matt Barrett, head of SJRA’s Flood Management Division. Said Barrett, “SJRA’s jurisdiction does not include Harris County, so projects constructed in Harris County would have to be led by HCFCD.”

Distant Chances for Other Flood Mitigation

That said, Barrett also volunteered that SJRA has partnerships with both HCFCD and the City of Houston. The entities work together on multiple projects from the San Jacinto River Basin Master Drainage Plan. But finding funding remains a challenge. And large scale projects are not quick to implement.

That brings us full circle to the original question in the headline. What was or is the best thing(s) homeowners can do to reduce their flooding chances? In my opinion:

I’m not a professional engineer and I do not render professional engineering opinions. But I have interviewed a lot of flood victims who wish they could turn back the hands of time and build on higher ground.

Foundation being endangered by riverbank erosion.

If you have the slightest qualms about flooding when purchasing property, make sure you consult a professional engineer to evaluate your risk and mitigation options.

Posted by Bob Rehak on 8/20/24

2548 Days since Hurricane Harvey

The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.