Tag Archive for: Texas

Texas Ranks #2 in States with Most Flood Damage

It’s easy to forget flooding in the middle of a drought. But we should never forget that Texas ranks #2 in states with the most flood damage. This and other statistics below demonstrate why we shouldn’t become complacent.

Debris pile from Imelda flood in Elm Grove Village (Kingwood).

Different Measures, Similar Rankings

Many ways exist to rank flood-prone areas and Texas ranks high on most of them.

  • National Flood Insurance Plan (NFIP) payouts? Texas ranks #2 after Louisiana between 1978-2021.
  • Most hurricanes? Out of the 300 hurricanes that made landfall in the US since 1851, Texas ranks #2 after Florida with 66 hitting the Lone Star state – 22% of the U.S. total.
  • Percentage of state’s total population living in floodplains? Texas ties for 10th according to a 2017 study. But a 2023 TWDB study shows that 20% of Texans now live in floodplains; that would tie us for 3rd if nothing else changed.
  • Most disaster declarations? Texas ranks #2 when considering all types.
  • Flood deaths? Texas ranks #1. Two hundred people died between 2010 and 2022. Over a longer period of time, 1959-2014, the state had over 850 flood deaths.
  • More Texans live in floodplains (one in five) than the entire populations of 30 other states.

Harris County Ranking

As bad as the Texas statistics are, Harris County’s are even worse.

Between 1978 and 2021, Harris County led all counties in the the entire country for NFIP claims filed (171,300), about 44% of the total claims for all of Texas.

Moreover, 42% of all Texans living in floodplains live in the San Jacinto watershed. The number of floodplain dwellers in the San Jacinto watershed alone exceeds the population of 15 states and the District of Columbia.

A Big Target

It’s important to look at many different measures, because no one measure conveys the full picture. For instance:

  • Number of hurricanes also reflects miles of subtropical shoreline.
  • The sheer size and population of Texas make it rank high on many measures. Said another way, we are a big target.
  • The high clay content of our soils discourages infiltration and encourages runoff of rainfall.
  • Dollar losses may depend as much as on affluence or population density in floodplains as the severity of flooding.
  • Dollar losses in Texas also reflect old building codes in many locations.

And then there’s the huge number of mobile homes in Texas. They are notoriously susceptible to high winds, like those often associated with hurricanes.

Their placement also makes them more vulnerable to flooding than other types of housing. A study by Headwaters Economics found that one in seven mobile homes is located in an area with high flood risk, compared to one in 10 for all other housing types.

Texas, a Leader in…

Texas leads the nation in many things: oil, gas, cotton, job creation, economic expansion and more. Unfortunately, we’re also a leader in flooding.

Better land-use and building codes could certainly help reduce the flooding. But will the state’s new flood plan recommend that? The focus seems to be on flood mitigation more than flood prevention.

The San Jacinto Regional Flood Planning Group recommended $46 billion worth of studies and mitigation projects in its regional plan. And the San Jacinto is just one of 15 watersheds in the state!

In sharp contrast to the magnitude of mitigation needs, the legislature voted only approximately $1 billion for flood prevention projects this year.

That’s enough to make a dent in the state’s budget, but not the problem. Perhaps we need to re-examine our priorities.

Posted by Bob Rehak on September 4, 2023, Labor Day

2197 Days since Hurricane Harvey


In Harm’s Way – To Build or Not to Build?

Texas and Maryland represent opposite ends of the political spectrum. So, it’s not too surprising that floodplain regulations in the two areas differ radically. When it comes to building in harm’s way, most municipalities and counties in the Houston region allow development in the floodplain with certain precautions. But several counties in Maryland prohibit floodplain building altogether. One even requires developers to deed floodplain land to the county.

In contrast, Texas developers even fight for the right to build in floodways!

Looking E toward Lake Houston in distance along the floodway of the San Jacinto West Fork. Photo taken July 2020.

The right to develop floodway land in the left foreground above was the subject of an eight-year lawsuit between a developer and the City of Houston.

Let’s examine the differences more closely.

Floodways vs. Floodplains

FEMA defines a floodway as the main channel of a river PLUS adjacent land that must remain free of development in order to avoid flooding areas upstream.

A floodplain extends farther out, usually to the edge of a valley. Floodplains flood repeatedly. Frequency and depth depend on rainfall and elevation within the floodplain. The area in the photo above flooded 53 times since Lake Houston was built 67 years ago. It even flooded SIX times in ONE year.

Houston Building Regulations

During Harvey, more than 150,000 structures in Harris County flooded. The area shown above went under 28 feet of water.

After Hurricane Harvey, Houston made its building regulations in floodplains more stringent. This table by the engineering firm WGA summarizes the changes.

From WGA

The idea: by building higher, you build safer.

Regulations also address the foundation type and “fill” practices.

However, builders can still move dirt around inside the floodplain. They use a practice called “cut and fill.” Example: they take dirt out of a stormwater detention basin and use it to elevate slabs. That way they don’t reduce the area available to store floodwater.

These regulations do nothing to make homes already built in a floodplain safer. They only affect new building.

And they only make people safer to the extent that engineers can accurately predict the future. The future includes both rainfall and upstream development.

In the case of Harvey, remember that FEMA had revised flood maps just 10 years earlier. Now it’s revising them again.

The point: under the “there are ways to build here safely” philosophy, your “safety” is based on imperfect knowledge, changing conditions, changing regulations and shifting estimates.

Sample Maryland Regulations

Maryland takes a different approach to building in harm’s way. It says “Don’t.”

The State of Maryland provides model floodplain regulations. Section 4.2(b)1 states: “Subdivision proposals shall be laid out such that proposed building pads are located outside of the special flood hazard area and any portion of platted lots that include land areas that are below the base flood elevation shall be used for other purposes, deed restricted, or otherwise protected to preserve it as open space.”

Counties and Communities implement their own floodplain regulations. I haven’t checked every county, but found that Howard County:

  • Prohibits any new structures in the 100-year floodplain. See page 152.
  • Requires subdivisions to either a) deed land in floodplains to the county or b) grant floodplain easements to the county. (Page 136)
  • Prohibits storing building materials in a floodplain. (Page 136)
  • Prohibits clearing, excavating, filling or altering drainage in floodplains. (Page 136)
  • Will not issue variances for projects within floodways that result in any flood discharge levels (Page 139)

Montgomery County, Maryland, has prohibited residential development in 100-year floodplains since 2007. (Page 4).

Frederick County, Maryland, states that no development has occurred in its floodplains in the past 10 years.

Two Different Philosophies

The Texas philosophy says, “There are ways to build safely in flood-prone areas.” The Maryland philosophy seems to say, “It’s safer not to.”

It’s difficult to say objectively which is better/safer. The regulations are designed for different different people in different areas: Rural vs urban. Hilly vs. flat. Temperate vs. Subtropical.

But I will say this. As I read Howard County’s Hazard Mitigation Plan, the number of homes that could be damaged in a 100-year flood – ten – and a 500-year flood – twenty – shocked me. (Page 39). Compare that to the 154,000 structures damaged in Harris County during Harvey. Well, no, don’t. There is no comparison.

Posted by Bob Rehak on 12/4/2022

1923 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.

Why Does the State that Leads the Nation in Billion-Dollar Weather Disasters Resist Minimum Drainage Standards?

Every once in a while, thoughts collide in a way that makes you see the world more clearly. Such a collision happened today. I suddenly realized that Texas, the state that leads the nation in billion-dollar, weather-and-climate related disasters, also has many developers plus city and county officials pushing back against higher minimum drainage standards that would reduce flooding. At a time when those disasters are increasing in frequency!

How Proposed Drainage Standards Will Affect Developers

My last post talked about “Minimum Drainage Standard Recommendations for Communities In or Draining Into Harris County.” A reader asked how the proposed changes would affect developers.

I replied, “The proposed changes would force developers in the future to install detention ponds and storm drains large enough to help reduce flooding. It would also prohibit them from reducing the floodwater storage capacity of the 500 year floodplain. Finally, it would force them to raise the level of homes above the 500-year floodplain or flood-proof them.”

Then I added, “From a flood prevention point of view, these are all good things. But from a developer’s point of view, they add expense. If you buy a home in an area that complies with these standards, it will probably mean a higher-priced, but much safer home. I hear that developers and some civic officials are already pushing back against these proposed changes.”

Natural Disaster Costs, Frequencies

After sending the reply, I went to the NOAA site to find information about natural disasters, their costs, their frequency and their primary locations.

I found this fascinating story about the increasing frequency of billion-dollar weather disasters. I pulled the three charts below from it.

Source: NOAA.

The last decade had twice as many billion-dollar weather disasters as the previous decade and four times more than the decade of the 1980s. The last five years had 69% of all such disasters in the entire 40 year period.

Tropical Cyclones and flooding comprised 29.5% all these billion-dollar disasters.

Source: NOAA.

Reason for Increasing Costs, Even After Adjusting for Inflation

In explaining these rising costs, NOAA says, “These trends are … complicated by the fact that much of the growth has taken place in vulnerable areas like coasts and river floodplains. Vulnerability is especially high where building codes are insufficient for reducing damage from extreme events.”

Texas Leads Nation

And who leads the nation in billion-dollar, weather-and-climate-related disasters? Texas.

Connecting Some Tragic Dots

So there you have it.

The state with the most billion-dollar disasters has many developers and civic leaders pushing back against higher minimum drainage standards at a time when major weather disasters are increasing.

Food for thought as this debate begins. Kind of makes you wonder about the wisdom of permitting starter homes in flood plains next to raging rivers, building 2200 acre developments without any detention ponds, and encouraging developers to get their water to rivers faster in floods.

New Northpark Woods development in Montgomery County next to San Jacinto West Fork and its sand pits.

Posted by Bob Rehak on 6/8/2020

1014 Days after Hurricane Harvey and 263 after Imelda

Researching Sand-Mining Best Management Practices, or Lack Thereof, In Texas

“Say what?”

House Bill 571 became the law of Texas in 2011. It requires sand miners to register with the state and follow “applicable environmental laws and rules.” So I put on my Sherlock Holmes hat and tried to determine what those were. After weeks of searching, I had my first clue as to why sand mines on the San Jacinto don’t follow guidelines that are common in other states.

The Texas Commission on Environmental Quality (TCEQ) website is bewildering. TCEQ documents posted online contain:

Simply googling “Texas sand mining best management practices (BMPs)” does not hit the mother lode. So you keep on searching, not knowing whether the information doesn’t exist or you’re just searching the wrong way. You keep thinking, “With a state as business-friendly as Texas, there must be a clear, simple articulation of guidelines somewhere!”

I finally gave up and asked someone at TCEQ to just send me environmental rules, regulations and BMPs for sand mining. It took three tries, but yesterday, I finally got usable information. And the answer is…! THERE ARE NONE FOR THIS PART OF TEXAS … with the exception of  a few EPA guidelines about refueling trucks within sand mines, some elements of the Clean Water Act, and a couple pages in a 133 page application.

The person helping me at TCEQ said that there appear to be:

  • No rules that include a setback distance between a sand mine and the San Jacinto River.
  • No restrictions on TCEQ permitting of sand mines in flood prone areas.

Texas does have guidelines for sand mining along the Brazos River in the John Graves scenic area of the Edwards Aquifer. However, they don’t apply to the San Jacinto River. And they have huge loopholes. For instance, see section 2.5 Stream Crossings and Buffers on Page 8. “Haul-road crossings through the buffer zones should be constructed ONLY WHEN NECESSARY [emphasis added].” 

The closest we come to articulating BMPs for sand mining along the San Jacinto: two pages within a PERMIT APPLICATION (see pages 62 and 63 of 166) to operate a sand mine. There are also some attachments to a letter from the TCEQ to the U.S. Army Corps of Engineers about the nationwide permitting process in Texas (see image at top of page). Neither of these are intuitive places to search for BMPs.

The experience of researching Best Management Practices for sand mining in Texas reminded me of filling out an IRS tax form – minus all the clarity in the IRS forms.

This lack of clarity is a big part of our problem in my opinion.

So what is a burly, cigar-chomping sand miner wearing a Caterpillar gimme cap on a bulldozer supposed to do? Put the dozer in gear and make money, of course. End of rant.

Posted on June 28, 2018 by Bob Rehak

303 Days since Hurricane Harvey

Do Local Sand Mines Follow Best Management Practices?

Note: This is the first article in a series on sand mine best management practices. It focuses on insufficient natural buffers between the mines and the San Jacinto river. Subsequent posts will focus on land clearing, site reclamation practices, and more.

A comparison of sand mining actual and best management practices found that performance shortfalls in local mines exacerbate sedimentation in the San Jacinto River, contrary to assertions by the Texas Aggregate and Concrete Association (TACA) that sand mining has environmental benefits.

Proximity of mines to San Jacinto River in non-flood conditions.

TACA claims that when a river floods, the current is so weak that sand and sediment are deposited inside of mines. An analysis of satellite and aerial photos shows, though, that the current is strong enough to break dikes, destroy roads, re-route the river through mines, and carry sediment downstream.

TACA sounds eerily reminiscent of Richard Pryor when his wife caught him in bed with another woman. “Who you going to believe? Me or your lyin’ eyes?”

In at least one case, a broken dike has gone unrepaired for years while pollution continues to escape into the San Jacinto, the main source of water for Lake Houston and millions of people.

Dangers of Sand Mining

Numerous states and countries acknowledge the following risks of sand mining. Most impose regulations on the industry because sand and silt washed downstream from mines can:

  • Impair water quality
  • Increase water treatment costs
  • Impair wildlife and fish habitat
  • Reduce carrying capacity of rivers and streams
  • Reduce the volume of lakes
  • Block drainage ditches
  • Contribute to flooding
  • Impose dredging expenses on taxpayers
  • Ruin recreation

Louisiana: Leader in Communicating Best Practices

The Louisiana Best Management Practices Guide to sand mining is one of the most concise, candid and clearly written guides in the world. Government and industry developed it together. The refreshingly honest introduction states:

  • “Sand and gravel mining operations can potentially cause off-site impacts to water quality if site planning and BMPs are not factored into every aspect of the mining operation.”
  • “…BMPs … should be utilized … to prevent pollutants from leaving the mining operation.”
  • “Siltation is considered the highest nonpoint source priority of concern in wetland areas and the second highest priority affecting lakes (1992 Report to Congress).”
  • “Mining related activities have been estimated to cause 7 percent of the nation’s nonpoint source impacts to lakes and 17 percent to coastal waters.”

Comparing Texas Practices to Other Areas’

Texas does not make it clear what the state’s best management practices (BMPs) for sand mines are. So how do sand mines along the San Jacinto measure up to other states’ and countries’ guidelines? Not well.

One focus of their BMPs is the use of buffer zones, setbacks and strips of vegetation to reduce erosion and control sedimentation. The minimum distance between mine and river in most cases is 100 feet. Some specify more.

  • Alaska, for instance, discourages mines from locating within 1000 feet of a public water source, i.e., the San Jacinto which feeds Lake Houston, the main drinking water source for millions of people. The minimum near other bodies of water in Alaska is 200 feet.
  • Malaysia specifies a 50 meter setback (164 feet) from all river channels.
  • Australia prohibits sand mining in sensitive areas altogether.

In Texas along the San Jacinto, miners often excavate to within 40-50 feet of rivers, and remove vegetation to build dirt roads on the remaining narrow strip between the mine and the river. These thin, sandy barriers provide little defense against floods. They have been repeatedly breached, as you will see below. The river often runs right through mines, carrying sand and sediment downstream.

Types of Barriers against Sedimentation

Louisiana mandates a minimum 100-foot buffer adjacent to perennial streams. The state recommends a dual defense against sedimentation: vegetation and structural measures. Their best practices guide states, “Vegetation is an inexpensive and effective way to protect soil from erosion. It also decreases erosion from flowing water by reducing its velocity. Roots hold soil and increase infiltration. Topsoil should be added where existing soils are not suitable for adequate vegetative growth.”

Vegetative controls include:

  • Maintaining buffer zones between mine and river
  • Sod stabilization techniques. Sodding can be more than 99 percent effective in reducing erosion.
  • Protection of trees involves preserving and protecting selected trees that exist on the site prior to development.
  • Temporary and permanent seeding

Structural controls include:

  • Diversion ridges, berms or channels of stabilized soil
  • Silt fences
  • Sediment basins with banks sloped at 2:1 or less
  • Dikes – Must be well compacted and vegetated, with an outlet pipe or coarse aggregate spillway
  • Riprap protection – at the outlet end of culverts or channels to reduce the depth, velocity and energy of water so that the flow will not erode the receiving stream.
  • Check dams – Small dams less than 2 feet high constructed across swales or drainage ditches to reduce flow velocity and erosion.
  • Aggregate stabilized site entrances – at least 50 feet long to reduce sediment tracked onto public roads. Tire washing may also be needed.
  • Good housekeeping practices for fuel, debris, sediment from unstabilized areas, etc.
  • Post-construction stormwater management measures
  • Retention ponds
  • Vegetated swales and natural depressions that filter sediments from runoff with side slopes of 4:1 or less.

A Visual Comparison

Note the images below. The first represents the ideal; it is taken from the Louisiana BMP guide. The rest are from the West Fork of the San Jacinto in the last three years.

Image of ideal stream bank from Louisiana Sand Mining Best Practices Guide. Note vegetation, grass, gradual slope and aquatic plants.

West Fork Sand Mine,  9/14/2018. During Harvey, 150,000 cubic feet per second came rushing down this narrow channel and flooded 20 square miles of exposed sand in more than a dozen different mines.

Consequences of NOT Following BMPs

The image above and the following images all come from a small area of investigation shown below.

2.1 miles from Northpark Drive and US59, and 3.1 miles upstream from the US59 bridge.

The following images demonstrate what happens when miners work too close to the river. Numbers on the first image correspond to close-ups that follow.

Inundation of sand mines during Harvey on 8/30/17. Numbers correspond to close-ups below.  All photos courtesy of Google Earth.

1 – Rapids within sand mine.

2 – Water rushing into mine, creating turbulence.

3 – Water takes a shortcut across meander through mine.

4 – Washed out road INSIDE sand mine during Harvey. 

5 -Sand bars within sand mine in conjunction with ruptured dikes prove sand was carried downstream. Photo taken on 10/28/2017 (after Harvey).

In a white paper circulated among Texas state legislators called The Societal and Environmental Benefits of Sand MiningTACA insists, “When [water invades a sand mine during a flood], the velocity of the water slows significantly, losing its ability to keep sediments in suspension and the stream or river begins to deposit its sediment load. When flood waters back into an area where a sand and gravel pit is located, the pit becomes a sediment trap for the flood waters and their sediments.” This series of photos directly refute TACA’s claims.

Why do we allow sand mines to operate in areas that flood repeatedly and violently, so near the drinking water source for millions of people?

Un-repaired Dike Still Leaks Sediment after 3 Years

Are the mines following Best Management Practices? The dike on the right in the images below ruptured in 2015 and still has not been repaired. Note sediment streaming into the West Fork.

Dike ruptured during flood in 2015 (see image below). It continues to spew sediment into the river.

Geologists say that once a river “captures” a sand mine, it repeatedly tries to take that same route in subsequent floods. This is a direct consequence of mining too close to the river. 

Cautionary Advice from India

Sustainable Sand Mining Management Guidelines from India state, “Floodplain Extraction should be set back from the Main Channel. In a dynamic alluvial system, it is not uncommon for meanders to migrate across a floodplain. In areas where sand and gravel occurs on floodplains or terraces, there is a potential for the river channel to migrate toward the pit. If the river erodes through the area left between the excavated pit and the river, there is a potential for “river capture,” a situation where the low-flow channel is diverted though the pit. In order to avoid river capture, excavation pits should be set back from the river to provide a buffer, and should be designed to withstand the 100-year flood… Adequate buffer widths and reduced pit slope gradients are preferred over engineered structures which require maintenance in perpetuity.”

Sand Miners Externalize Costs

Because these West Fork sand mines did not consider violent floods in their design and construction criteria, taxpayers downstream bear the cost of remediation. Dredging of the West Fork will cost tens of millions of dollars – for the initial 2.1 mile phase alone! That doesn’t even include recurring and unnecessarily high costs of water treatment because of turbidity.

Posted 6/24/18 by Bob Rehak

299 days since Hurricane Harvey