Final Report on Imelda Says 62% of Flooding Outside of 100-Year Floodplain

Harris County Flood Control District released its final report on Tropical Storm Imelda this morning. It’s a work of incredible scholarship. If you really want to know what made this storm different, this is a must read.

While Imelda was the fourth wettest storm in Texas history when measured by total rainfall, Imelda produced incredible short duration rainfall rates that exceeded Harvey in the 5-, 15-, and 30-minute time periods. And that is the key to understanding why more homes flooded in the 500-year floodplain than the 100-year floodplain.

Few Structures In Lake Houston Area Flooded from River

Says Jeff Lindner, Harris County meteorologist, “Much of the structure flooding that occurred in the Kingwood area was not a result of flooding from the river, but instead flooding of local drainage systems that were overwhelmed from the intense short duration rainfall rates. Harvey remains the flood of record along the West Fork of the San Jacinto River.”

Almost Two-Thirds of Flooded Homes Outside 100-year Floodplain

Similar to other recent flooding events in Harris County a large number of flooded homes were located outside the 1% (100-yr) floodplain. Of the 3,990 homes flooded from Imelda, 2,479 (62%) were outside the 1% (100-yr) floodplain. 1,511 (38%) of the flooded homes were located inside the 1% (100-yr) floodplain.

“While house flooding did occur from creeks and bayous overflowing their banks, a large majority of the house flooding was a result of intense short duration rainfall rates overwhelming the internal drainage capacities and this is shown by the large number of homes that flooded outside the 1% (100-yr) floodplain,” says Lindner.

Rainfall Totals Throughout San Jacinto Watershed

See the actual rainfall measurements for gages throughout the San Jacinto Watershed below. All characterizations of floods (i.e., 100-year) are based on NOAA’s new Atlas 14 data.

San Jacinto River and Lake Houston
Cypress Creek
Spring Creek
Luce Bayou
Flooding of Local Tributaries: Green = 10-50 yr flood, Yellow = 50-100 yr, Red = 100-500 yr, based on high water marks.
1-Hour Peaks throughout county. Note blue bullseye over US59 and Beltway 8. That’s a 500-year intensity rate.
48 Hour Peaks throughout county. Notice extreme gradient from east to west. 28″ in northeast part of county and less than 2″ in the west.
Regional map. Parts of Liberty, Chambers and Jefferson Counties received a 1000-year rain. As bad as Imelda was, Harris County escaped the worst part of the storm.

Details Provide Clues to Reasons for Flooding

The final Imelda report has thousands of statistics for just about every location in the county and every time period between 5 minutes and 48 hours. Scanning it may give you a feeling for why you flooded or why you did not.

Increasing Frequency of Extreme Storms

The report also contains a discussion the number of extreme storms that have hit this area recently. Some key stats:

  • Three of five wettest tropical cyclones in Texas history occurred in the last 20 years (Imelda, Harvey, Allison)
  • Among Texas storms, four of the top five occurred in southeast Texas (Imelda, Harvey, Allison, and Claudette).
  • Imelda is also the 5th wettest tropical cyclone ever in the 48 contiguous United States.
  • Six of the wettest tropical cyclones in US history have occurred in Texas.
  • Six of the 10 wettest occurred in the last 22 years.
  • Three of the 10 wettest occurred in the last three years (Imelda, Florence, Harvey).

The table below shows the top ten wettest tropical cyclones by location and year in the 48 contiguous states.

Source: Harris County Flood Control final report on Imelda.

For the full report, click here.

Implications of Report Speak to Need for Change

Yesterday, I posted about an engineering company that made conservative and questionable assumptions about rainfall totals and more in their drainage analysis for Woodridge Village.

When far more homes flood in the 500 year flood plain than the 100, it’s clear that our infrastructure is not equipped to handle the kind of storms we’re now getting.

We can no longer allow developers and engineering companies to bet on the best case scenarios when the worst case scenarios are becoming the norm. We must start building infrastructure to handle bigger storms. The old norms are failing us.

For starters, we need Montgomery County to:

Posted by Bob Rehak on 11/11/2019

804 Days since Hurricane Harvey and 55 since Imelda

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

Questionable Assumptions by LJA Engineering May Have Compounded Elm Grove Flooding

Questionable assumptions about soil composition, rainfall patterns, wetlands and floodplain status for Perry Homes’ troubled Woodridge Village development may have compounded flooding in Elm Grove and North Kingwood Forest. Previously, I have focused on other more obvious issues, such as missing detention ponds and expected rainfall totals. However, Elm Grove resident Jeff Miller who has been studying the LJA Drainage Report, urged me to explore these additional issues.

Soil Type Closer to Clay than Sandy Loam

The LJA engineers doing the drainage analysis for Perry based their runoff calculations on a soil type called “sandy loam.” Different soil types absorb rainfall at radically different rates. According to 2011 data from Texas A & M Agrilife Extension, water infiltration rates for:

  • Sand = 2″ – 6″ per hour
  • Loam = .6″ – 2″ per hour
  • Clay = .2″ – .6″ per hour

Clay absorbs water very slowly, so rain turns into runoff quickly. Two photos below show what the Woodridge Village construction site looked like ONE WEEK AFTER a 2″ rain. It still had ponding water that did not soak in.

The northeastern portion of Woodridge Village looking southwest. Photo taken on 11/4/2019 one week after a 2″ rain. Note the ponding water that has not yet infiltrated.
A closer shot of the main portion of the north side of the site, also taken on 11/4/2019. Note the ponding water here, too. USGS characterized parts of this portion of the site as WETLANDS.
From the USGS National Wetlands Inventory. Note how the ponding water in the photo aligns with where the wetlands were.
Drone footage of southern section taken two days after May 7th flood. Courtesy of Jim Zura, Zura Productions.

In May, a retired local geologist from a major oil company estimated that the clay content in Woodridge soil was at least 50%, and could be as high as 80%. However, he could not commit to an exact figure.

Going by the A&M infiltration figures above and assuming an infiltration rate of 2″ per hour for a mixture of sand and loam, and contrasting that with the minimum infiltration rate for clay, .2″ per hour, you get a difference of 10X.

What does all this mean?

Based solely on soil type, the LJA Engineering report could err in its runoff calculations by as much as 10X.

Sections 1.1 and 2.1.3 of the LJA report discuss the runoff based on soil type. No matter how sophisticated the calculations, if you base them on the wrong soil type, the result will be inaccurate. “Garbage in, garbage out” as they say in the computer business.

Before clearcutting, there may have been more sandy loam in a thin surface layer. But contractors likely disturbed or buried that when they removed vegetation from the site and regraded the area.

If LJA wishes to challenge this, I will be happy to reprint their response verbatim. I would love to see their soil report.

But I would like to know how they explain the presence of ponding water throughout the entire northern section of Woodridge Village a full week after a two-inch rain. (Note that the northern section is the steepest and largest. It comprises 2/3rds of the Woodridge Village’s acreage.)

I took the aerial shots above at around 2PM on 11/4/2019. Here are the rainfall totals for the previous 7 days. Graph courtesy of Harris County Flood Warning System.

The Presence of Wetlands Should Have Been a Signal

The presence of wetlands should have been a signal to the developer, but the LJA report does not mention the word “wetlands” once.

Many residents who used to hike and bike this area before it was clearcut have told me that they could always find standing water there even in summer. Here’s an interesting article that explains why wetlands stay wet. The authors says, “Wetlands typically form in gently sloping or topographically convergent portions of a landscape, where surface and ground waters meet.” That certainly fits Woodridge Village.

As Miller says, “Drone footage; many photos; and the constant presence of water in the S-2 detention pond and the rectangular pond where N3 should be confirm that the ground is saturated. When the soil is totally wet, water will move over the surface.” And as LJA says in the intro to its report, “The project site naturally drains to Taylor Gully.”

And that’s exactly where so many people flooded when contractors accelerated the runoff through clearcutting and by not providing adequate detention.

Balanced Storm Assumption Rarely Accurate

Section 2.1 of the LJA report says that LJA models assumed a “balanced storm.” “This distribution is constructed such that the depth specified for any duration occurs during the central part of the storm (intensity position = 50%).” [Emphasis added.]

But as Jeff Johnson, the Montgomery County engineer, pointed out, using a “balanced storm” bases calculations on ideal assumptions. He also pointed out that only a small percentage of storms conform with ideal conditions. (Johnson made these remarks at a Montgomery County Commissioners Court meeting at which they discussed closing a loophole in flood regulations.)

According to the US Geological Survey, this graph represents a balanced storm.

In the ideal balanced storm, most of the accumulation happens in the middle of the storm.


But the May 7th and Imelda storms did not follow this pattern. The heavy rainfall was front-loaded in both.

More than half of the total rainfall during the May 7th event fell at the outset, not in the middle of the storm. Thus, it did not conform to the balanced storm model upon which LJA based its calculations.
During the 11 hours of rainfall from Imelda, more than 50% fell in the first three hours, and almost 80% in the first 4 hours. Thus, Imelda was also “front-heavy”.

LJA Assumed Woodridge Was Outside of 100-Year Floodplain

LJA also assumed (see section 1.5 of its report) that Woodridge Village was “outside of the 100-year floodplain.” For permitting purposes, that is technically true. LJA was going by accepted maps. But that area is not shown as flood plain only because FEMA did not model it. Note in the Montgomery County Flood Plain Map shown below how ALL FLOODPLAIN MAPPING STOPS AT THE COUNTY LINE.

That straight diagonal line you see is the Harris-Montgomery County Line.

Any engineer experienced in working with flood plains should know that physical boundaries do not stop abruptly at political boundaries. Any competent engineer should have questioned this.

Engineering Codes of Ethics Discourage Such Conduct

While LJA did what regulations required, they had a higher ethical obligation to protect people as licensed engineers. See the Code of Ethics of the NSPE – the National Society of Professional Engineers. It states:

“…engineers are expected to exhibit the highest standards of honesty and integrity. Engineering has a direct and vital impact on the quality of life for all people. Accordingly, the services provided by engineers require honesty, impartiality, fairness, and equity, and must be dedicated to the protection of the public health, safety, and welfare. Engineers must perform under a standard of professional behavior that requires adherence to the highest principles of ethical conduct.”

Under Fundamental Canons, the Society’s Code of Ethics also requires engineers to “Hold paramount the safety, health, and welfare of the public.”

Also see Professional Conduct and Ethics for Texas Engineers.

The latter states “In order to safeguard, life, health and property, to promote the public welfare, and to establish and maintain a high standard of integrity and practice, the rules relating to professional conduct in this title shall be binding on every person holding a license and on all firms authorized to offer or perform engineering services in Texas.” In this regard, LJA failed the people of Elm Grove and North Kingwood Forest dismally.

Overlooked Ethical Obligations Contribute to Dramatic Miscalculations

Ignoring the missing flood plain information, not mentioning wetlands, and mischaracterizing soil composition all contributed to dramatic miscalculations. Add those problems to ignoring new statistics that showed flood plain maps would need to be redrawn based on NOAA’s new Atlas 14, and that a 100-year storm would include 40% more rainfall.

Sometimes when you’re eager to make a project happen, optimism leads one to make “best-case” assumptions. But in my opinion, engineers should act on “worst-case” assumptions” to product public safety.

Sometimes, the cost of failure is simply unthinkable. This is one of them. Elm Grove flooding wasn’t as spectacular as a dam or a bridge failing, but it likely affected far more people.=

Webster and Spurlock law firms are currently trying to subpoena correspondence between LJA and Perry Homes and its subsidiaries. The Perry Homes gang is trying just as hard to stonewall production. It will be interesting to see what pressure, if any, they put on LJA to ignore these obvious problems…if the documents ever become public.

An even bigger ethical question: With such obvious problems, why did Montgomery County Commissioners and the City of Houston approve permits for this development?

Posted by Bob Rehak on 11/10/2019 with help from Jeff Miller and video from Jim Zura

803 Days after Hurricane Harvey and 51 after Imelda

The thoughts in this post represent my 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.

Woodridge Village Update: More Dirt, Denials, Delays

Twenty-three days ago, Houston Mayor Sylvester Turner read a letter to a packed town hall meeting at the Kingwood Community Center. The letter was from a lawyer named J. Carey Gray. Mr. Gray laid out a timetable for accelerating completion of the detention ponds on the troubled Perry Homes’ development, Woodridge Village, just north of Elm Grove. The first deliverable: completing the S2 pond in 30-45 days – even though it was already largely completed.

As of early this week, contractors have performed no new excavation work on the site since early August. See pictures below.

One Piece of Equipment Moves Closer to S2 Pond

This piece of Rebel Construction equipment moved from the site entrance to north of the S2 pond last Thursday. It looks as though its in danger of actually doing some work. Photo by Jeff Miller on 11/7/2019.

Dirt Continues to Flow From Construction Site

Construction has slowed to a virtual standstill for three months. Between that time and the time the photos below were taken, we had Imelda and a 2.12-inch rain on October 29.

On the 29th, yet more mud washed out of the development into the City’s storm drains, despite the City’s Cease and Desist Letter.

Source: HarrisCountyFWS.org
This and photos immediately below were taken on 10/29/2019 near Woodridge Village Construction entrance on Fair Grove Drive and Creek Manor Drive in Kingwood.
Dropping back a little farther, you can see the silty runoff from the construction site. Notice the contrast between that and the clear water coming from a resident’s lawn through the curb break.
Contrast appears a little clearer in this closeup.
You can see the contrast even better where the water enters this storm drain. Muddy water is coming from the construction site. Clear water from the neighborhood to the south.
These sand waves covered Fair Grove Drive just outside the construction site entrance...despite silt fencing.
Here’s a picture of water going into the S2 Detention pond at the north end of Village Springs Drive.
And here it is coming out of S2 into Taylor Gully. S2 is behind the trees on the left. This shot is looking north.

Of course, flooding, not sediment is the real issue in Elm Grove. However, sediment can block storm drains and contribute to flooding. That’s why the City has an ordinance prohibiting discharges of sediment into the City’s sewer system. It’s one area where the City has real leverage with the Perry gang. That’s why so much emphasis has been placed on sediment in this controversy.

City Inspectors Visit Site

Thursday and again Friday, City inspectors checked the construction site for discharges. We dodged a huge bullet Thursday. Parts of Houston received five inches of rain. But the Lake Houston Area received less than one inch.

Photo taken 11/7/2019 by Jeff Miller of a City Inspector photographing Woodridge S2 detention pond.
Photo taken 11/7/2019 by Jeff Miller shows same City Inspector walking along Taylor Gully just south of Woodridge.

Denials, Finger Pointing, Objections on Legal Front

Webster and Spurlock, lawyers for hundreds of Elm Grove flood victims, have brought another defendant into the suit. It is Texasite LLC of Montgomery, Texas. Legal filings do not describe exactly what the new defendant did on site. The company has no web site that I can find. Even the Texas Secretary of State can’t shed much light on the matter; the company’s Certificate of Formation simply says it is organized to “conduct lawful business.”

That said, whatever they allegedly did, they aren’t accepting responsibility for it. Texasite:

  • Denies they harmed anyone
  • Asserts that plaintiffs caused their own injuries through negligence
  • Asserts that third parties caused the damage. Those third parties include God.

In other legal news, Webster and Spurlock filed a notice of intent to take a deposition by written questions from LJA Engineering. The list of information they seek is two pages long.

PSWA and Figure Four Partners, two Perry Homes subsidiaries being sued, objected to items #2 and #3 on the list. They included “letters, emails, and other correspondence/communications between LJA Engineering & Surveying” and the defendants “with regard to the Woodridge Village Development.” The defendants argued in their objection that the request was overly broad because it didn’t limit the time period or subject matter. So sayeth Counselor J. Carey Gray, who wrote the overly vague letter to the City of Houston re: completion of the detention ponds. According to documents on file with the Harris County District Clerk, the judge has not yet ruled on Perry’s objection to production of the evidence.

Delays Also Continue on Construction of More Detention

I flew over the Woodridge Village construction site on Monday, 11/4 and saw no evidence of construction activity, despite the assurances made by Counselor Gray. The images below show the lack of activity from several different angles.

Looking N at the extreme western tail of the construction site that borders Woodland Hills Drive (left). This and all photos below taken on 11/4/2019.
Looking NE across the north and south sections of the site. Detention pond S1 runs along the diagonal tree line from the lower left. Detention Pond N2 is in the upper right. These two ponds comprise 23% of the total detention capacity by volume.
Detention pond N3 is supposed to go along the trees in the background to the left of the S2 pond. It has not been started yet. Notice the one piece of yellow equipment at work clearcutting more land on the middle left.
Close up of where the N3 pond will eventually go. It will start in the bottom left and curl around the upper right.
Looking west. No construction activity on the northeast corner of the site in the foreground.
From this angle, looking SW, it’s easy to see all the standing water on the site. We received two inches of rain SIX days before. So much for LJA’s assumption that this site contained sandy loam. The ponding water after such a long period suggests a high clay content. That in turn explains the rapid and huge runoff rates that flooded Elm Grove.
More ponding water indicating high clay content.
Looking west at the NW corner of the site. This is where the non-existent N1 pond should be.
Looking North. The largest detention pond on the site, N2, will go in that triangular green area (center). Contractors were supposed to deepen and enlarge it. The partial detention capacity you see here now was developed by Montgomery County in 2006 as mitigation for another site. So the detention capacity you see in this image, by itself, would not reduce Elm Grove flooding potential. Saying it did would be like trying to sell a ticket that someone else already bought.

I’m Shocked, Shocked I Tell You

So what are we to make of the continued lack of construction activity? To paraphrase the exchange between Strasser and Renault in the movie Casablanca, I am shocked – SHOCKED – Perry would promise the Mayor of Houston that it would accelerate construction of new detention ponds and then not do it.

Posted by Bob Rehak on 11/9/2019, with photos an updates from Jeff Miller.

802 Days since Hurricane Harvey and 50 Days since Imelda

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

Fox 26 Finds San Jacinto West Fork Still Flowing White; Source of Pollution Still Not Identified

Last Monday I photographed white water in the West Fork. Alarmed by what I saw, I sent photos to the TCEQ and SJRA. Then I posted about it last night. Fox 26 saw the post and decided to do some of its own investigating.

San Jacinto River running white has the Hallett sand mine on the West Fork. Photo taken on 11/4/2019.

Fox News Investigates Further

Today, Fox called for an interview. The reporter, Ivory Hecker, also called the TCEQ, the San Jacinto River Authority and Houston Public Works Department. Everybody, it seems is now investigating. Chuck Gilman of the SJRA says he has never seen anything like it.

Meanwhile, the river is still running white. Not AS white, but nothing like its normal color. Fox sent its own helicopter up today and documented a definite discoloration.

Here’s a link to Ms. Hecker’s segment on Fox. I include it here not because it contains an interview with me, but because it contains the results of her own investigation and interviews with others. It also has helicopter footage taken this afternoon showing that the river is still running white, albeit a dirtier white.

So far this week, the TCEQ, SJRA, and City of Houston have all launched investigations. None has reported results yet.

What Causes Color in Water

China has a Yellow River. Wyoming and Utah have a Green River. Colorado has a Blue River. And of course, Texas and Oklahoma share a Red River. Here’s an article about what makes water different colors. They include runoff, chemical spills, reflected light, color temperature, suspended particles, dissolved minerals, you name it. But the article never once mentions WHITE.

In happier times – Pre-Harvey – I drove to the Arctic Circle and photographed spectacular scenery along the way. In Alberta, Canada, I photographed some of the most intensely blue water I have ever seen anywhere. Given the pristine alpine location, you might think the lake in the photo below was naturally blue.

It’s not. Water is a clear colorless liquid. Things IN it give it color. The intense blue in the water below comes from the way suspended “rock flour” from the glaciers refracts light. Still, I’ll take it over San Jacinto white water any day.

In the mountains above Canmore, Alberta.

Best Theory so Far

According to Fox, Houston Public Works suspects the color is caused by suspended sediment from a sand mine. Although both of the mines I flew by on Monday were discharging water from their pits directly into the river, we just need to wait and see what water tests show and whether the discharges I witnessed had been permitted by the TCEQ.

The water was also white upstream from the two mines I photographed – just not as white. So it’s possible those two mines were not even involved. We should not jump to conclusions.

Better Ways to Monitor

Several things are certain at this point, however. Flyovers once every two years by the TCEQ are insufficient to catch issues like this. LandSat flies over Houston 18 times a day. It’s hard for taxpayers to understand why the TCEQ doesn’t use the satellite imagery that the federal government is already collecting anyway. It could provide a higher level of protection at a lower cost. I posed the same question last November to the TCEQ and never received a satisfactory answer.

Second, I have been told that there are ways to monitor the Total Suspended Solid (TSS) concentration in water above and below sand mines. Such gages would make a great way to narrow down the source of pollution and stop it quickly. The SJRA could and should demand such monitoring as part of the price of mining sand near its river banks.

Parting Thought

It’s also hard for people who pay sky-high, City-of-Houston water bills to understand why we allow people to dump things in the drinking water of two million people that raise our treatment costs. It just doesn’t seem right regardless of your politics.

Posted by Bob Rehak on 11.8.19

801 Days since Hurricane Harvey

The thoughts expressed in this post are my 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.

The Day That the San Jacinto West Fork Turned White

On Monday, November 4, I flew up the San Jacinto West Fork in a helicopter and was shocked by what I saw. The West Fork had turned milky white. Here are a series of shots starting at the confluence of the West Fork and Spring Creek and heading upstream. Spring Creek angles off to the top of the frame; the West Fork goes right.

Starting at the 59 Bridge…

Note the difference in color between Spring Creek and the West Fork, angling off the right side of the frame. Also note for contrast the normal looking browning water going into the West Fork from the woods at the bottom.
As we turned up the West Fork, I took this shot. Note the color of the pond at the top of the frame for comparison.
This is the first sand mine going upstream. Note the difference in the water heights between the pit (top) and the river bottom. Also note the pipe sending mine wastewater into the West Fork.

Moving North Past the First Mine

A little farther upstream, though, the water was still white.
I debated on adjectives: chalky or milky?

At the Hallett Mine North of Northpark Drive

The Hallett pond on the west side of the river was emptying into the West Fork. Hallett is north of Northpark Road off Sorters.
On the northern side of the Hallett Mine, we spotted this giant breach that had also been open in October. Notice the eroded shoreline opposite the breach. Water must have shot out of that pit with some force.
This was as far north as we went: the northernmost part of the Hallett Mine. Note the color of the pond on the right for contrast. The water looked less white than farther downstream, but still far from its normal brownish color that you see in the pond.

TCEQ Investigating White West Fork

I don’t think we ever found the source of the whitish discoloration although we found several mines contributing to it. When we got to the northern part of the Hallett Mine, time, fuel and air traffic restrictions dictated that we break off the exploration. So…

These photos were sent to the TCEQ and SJRA for investigation. This is the major source of Houston’s drinking water, folks!

Posted by Bob Rehak on 11/7/2019

800 Days since Hurricane Harvey

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

New Union Pacific Railroad Bridge over San Jacinto Will Have Wider Spans

Many readers have asked what the Union Pacific Railroad (UP) is doing to its bridge over the San Jacinto near US59. According to the Houston Chronicle, UP is widening the spans to reduce the potential for catastrophic damage in the event of another storm like Harvey.

If you have children or grandchildren that love trains, cranes and building things, you’ll want to share this post with them. It’s a real life example of a massive (re)construction project in the middle of difficult circumstances and a testament to the kind of brainpower and brawn that built this country.

A New Bridge Rises from the Old

These photos taken on Monday of this week (11.4.2019) illustrate how a new Union Pacific bridge is rising in the same place as the old one. With wider spans, the bridge will now also require different construction.

Wider concrete supports and a steel bed will replace the old tubular supports. UP constructed a temporary bridge next to the new bridge to hold the construction cranes.
This wide shot taken on 11/4/2019 shows how much wider the new spans are compared to the old.

Problems with Old Union Pacific Bridge

Back in 2017, the supports of the old bridge caught many trees swept downstream by Harvey. As you can see in these photos, the old bridge had two or three times the number of supports. David Seitzinger, a Kingwood resident, identified the supports and the trees they caught as a contributor to flooding in this analysis of water levels, flows and timing during Hurricane Harvey.

Photo from September 14, 2017. Harvey knocked out the old bridge. It took weeks to repair and shut down northbound rail traffic.
During Harvey, those old supports caught debris floating downstream that partially dammed the river and destroyed the railroad. Photo from UP report on flood.

A Marvel of Engineering Ingenuity

Current photo shows how the narrow spacing of supports for the temporary bridge are still catching debris floating downstream.
When complete, the bridge will border Harris County Precinct 4’s new Edgewater Park (lower right).
The wider spans should help protect the commercial areas south of the river from flooding.

This presentation explains the importance of railroads to the region’s economy and damage that Harvey did to UP.

The progress of this construction is another encouraging sign of recovery from Harvey.

Posted by Bob Rehak on 11/6/2019 with thanks to the Union Pacific Railroad

799 Days after Hurricane Harvey

Triple PG Sand Mine Finally Starts Plugging Breach on White Oak Creek

In September, Imelda caused the Triple PG sand mine dikes to breach in multiple locations. As a result, the mine’s process water flushed into the drinking water for millions of people. When the owners left the breaches open for weeks, the Texas Commission on Environmental Quality (TCEQ) filed a harsh report with the Texas Attorney General. The AG then sued the mine on October 11.

While the Triple PG owners immediately rushed to seal off the most visible breach into Caney Creek on October 12, other breaches still remain open.

On Tuesday of this week, 46 days after the flood, the Triple PG mine was finally attempting to seal off the main breach into White Oak Creek, another tributary of Lake Houston. I took all of the photos below during the afternoon of November 4, 2019.

The TCEQ had fined Triple PG in 2015. TCEQ again fined the mine in May of this year for allowing process water to escape into the City’s drinking water for weeks. That fine totaled more than $18,000. But when it happened again in September, the Texas Attorney General sued the owners for more a million dollars.

Triple PG White Oak Creek Breach Still Open on 11.4.19

After the AG suit, I thought repairs to all breaches would follow quickly. So I rented a helicopter on 11.4.2019 to check their status. That’s when I took all the photos below. What I saw should have shocked me, but sadly, it did not.

Miners had not yet sealed the White Oak breach. And a white substance was floating out of the mine through it.

Triple PG attempts to repair breach to White Oak Creek on 11/4/2019. The narrow, washed out section of the road on the right looks like it might have been a previous attempt at a repair that failed already.

Meanwhile, Repairs to Triple PG Caney Creek Breach Failing Already

Meanwhile, the breach repair (below), first photographed on October 12, appeared to be slumping into Caney Creek already. Notice how the road is collapsing near the trees at the bottom of the frame in this photo. Glad I’m not driving heavy equipment over that road! Quick call the MSHA! Notice also the difference in the water elevation on either side.

The repair to the Caney Creek breach completed last month appears to be failing already.
Looking west over Caney Creek in the foreground. Erosion is already visible in this side shot of the same repair from a different angle.

Water appears to be piping through the dirt in the repaired breach. Note the wet appearance in several places that also exhibit erosion near the bottom of the dike. Piping is one of the major causes of dike failure. Water seeps under the dike creating channels which undermine it.

Trapped Stormwater: A Problem for Mines in Floodways

A high and constant level of the water in a such a mine creates outward pressure on dikes that invites failure. A spokesman for the Mine Safety and Health Administration said that typically mines must find ways to get rid of excess water after heavy rains or risk breaches. Some try engineered solutions such as spillways. However, Triple PG mine also faces environmental constraints. Specifically, Triple PG cannot flush its process water into the City’s drinking water. Especially when the Attorney General is looking over their shoulder.

My conclusion. Floodways are just dangerous places to build sand mines and this mine sits in two floodways.

Six More Breaches

Here’s a second breach into Caney Creek that they haven’t even started repairing. It appears that water overflowed the pit and started traversing down the side on a diagonal. Note the tree leaning into the creek in the sandy area at the bottom.
And a third breach into Caney Creek. But at least they repaired the road above this one.
And a fourth breach into Caney Creek.
And a second breach into White Oak Creek behind the mine’s stockpile.
And the start of an exit breach along the mine’s southern perimeter where so many homes in Walden Woods flooded. To my eye, it appears that there is little or no elevation difference between the mine road and surrounding homes. So I am not even sure that this qualifies as a dike, or is just the edge of a pond.
And the mother of all breaches on the north side of the mine.

Tick Tock Tick Tock

The suit filed by the Texas Attorney General seeks monetary relief of “not more than $1 million.” But here’s where it gets interesting. The Texas Water Code section 7.102 states that penalties can range up to $25,000 per day for EACH day of EACH violation. It also specifies that “Each day of a CONTINUING violation is a SEPARATE violation.”

With all of these other breaches (that the TCEQ investigators could not see when they first inspected the mine because of washed out roads), these violations could add up quickly. Let’s see. 48 days x $25,000 = $1,200,000 for each breach. If the AG amended the lawsuit, that could add up to some serious bank.

Posted by Bob Rehak on 11.6.2019

799 Days since Hurricane Harvey and 48 since Imelda

The thoughts expressed in this post represent my 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.

SJRA Peak Flow Map from Imelda Shows 1500X Difference Between East/West Sides of Watershed

Here’s a science lesson for the entire family. The SJRA’s peak streamflow and rainfall map for Imelda demonstrated how rain can fall heavily over one part of a watershed and barely touch another. There are huge implications for flooding.

For a high resolution PDF suitable for printing, click here.

Peak Streamflows West to East Vary by 1500X

Note how the gage at Spring Creek in Tomball recorded a peak flow of 22.7 cubic feet per second. The East Fork gage in New Caney registered 34,600 cubic feet per second. That’s a difference of more than 1500X in the peak flow rates!

Rainfall Totals Range from 0 to 30 Inches in 24 miles

The blue figures represent precipitation. That same gage in Tomball recorded none. But a little further east, they picked up more than 5 inches; almost 10 at I-45; more than 15 at I-69, and almost 30 in New Caney.

This is why you need to look at gages upstream on YOUR tributary when flooding is possible! Someday, textbooks will use this map to dramatize that lesson.

Posted by Bob Rehak on 11/5/2019

798 days since Hurricane Harvey and 47 since Imelda

Why You Need to Vote for Mayor Tuesday if You Haven’t Already

This will be the most important mayoral election in Kingwood’s history, but the turnout in early voting was dismal. You would think people don’t care about flooding or that it’s been fixed already. Well, they should care. It hasn’t been fixed.

Below are some photos that show the difference pre- and post-dredging in the mouth bar area of the West Fork.

Match photos of the mouth bar taken after Harvey and Monday 11.4.2019.

Before Dredging: August 2019

This is an Atascocita Point resident walking out to the dredging operation in August.

After Dredging: November 2019

The 500,000 cubic yards that the Corps removed from the West Fork mouth bar barely scratched the surface. Think that’s an exaggeration? RD Kissling took this photo Sunday, 11.3.19, 700 yards south of the mouth bar as he stood in water just a little more than one foot deep. The channel at this point should be at least 400 feet wide and 30 feet deep to match the depth near Kings Harbor.

Photo taken Sunday November 3, 2019 approximately 700 yards south of the mouth bar by RD Kissling. That’s almost half a mile. Like icebergs, the majority of sandbars exists belong the surface.
Where Kissling took the shot in knee-deep water.

The Two-Year Old Controversy that Started Twenty Years Ago

So what does all this have to do with the contest for Mayor? The current mayor has been arguing with FEMA and the Corps for 798 days over how much Harvey deposited in the mouth bar. We’ve had dueling studies. Endless meetings. Countless stories. And still nothing has changed significantly in this most important region of the river.

The City has neglected its obligation to maintain this area for more than 20 years. Engineers warned for decades of the danger and not a penny of the City’s money was spent on dredging.

The City wants FEMA to remove 1.4 million cubic yards, but FEMA claims it would be funding “deferred maintenance” by the City.

Lest we forget, the mouth bar forms a sediment dam behind the dam that contributed to the flooding of more than 4,000 homes behind it and approximately half the businesses in the Lake Houston Chamber.

Bill King’s Plan to Get it Done

Today, Bill King held a press conference in Kings Point to lay out his plan for dealing with the mouth bar. It includes a $10 million contribution from the City to increase the funds already allocated by the State and County. The money would be used to establish a permanent maintenance dredging program.

According to a television reporter and the press conference, Mayor Sylvester Turner accused King of campaign rhetoric on the mouth bar issue.

This isn’t about rhetoric. It’s about survival.

If you care about Kingwood, if you care about your home, if you’re tired of waiting…please go to the polls tomorrow and vote. I voted for King. He’s the only candidate with a workable plan to address flooding in my opinion. But please just vote for the candidate of your choice. Not voting sends a message to the Mayor that we’re happy.

After 798 days of argument, letter writing, and meetings, it’s time for results. If re-elected, Sylvester Turner will be term-limited. Without another election hanging over his head, I just don’t see much improvement in the current situation.

For More Information

To learn more about the flood plans of the three leading candidates, read this post.

To learn more about Kings plan to address the mouth bar, see this newsletter.

If you would like more background about the mouth bar itself, please review this presentation about the Mouth Bar by Tim Garfield, RD Kissling, and me. Garfield and Kissling were both senior level geologists for one of the world’s largest oil companies before retiring. They provided the content. I just helped them shape their thoughts.

Kissling also wrote this open letter to the City of Houston that spells out problems with the Tetra Tech study that the City commissioned at the Corps’ request.

Please Also Vote FOR Prop 8

Among other items on the ballot, one of the most important from a flood mitigation perspective is Prop 8. Prop 8 would make money available from the Texas Rainy Day Fund to help provide low interest loans and grants to cities and counties. The money could be used to qualify for matching funds from the federal government. The lack of local matching funds has delayed many worthy flood mitigation projects identified after Harvey. Prop 8 should help fund many mitigation projects, bring more of our federal tax dollars back to Texas, and reduce flood risk by accelerating both grant applications and construction. Vote FOR.

Posted by Bob Rehak on November 5, 2019, election day

798 Days after Hurricane Harvey

Rape of the West Fork: A Photo Essay

Thirteen years ago, American Rivers named the West Fork of the San Jacinto one of the ten most endangered rivers in America. It’s only gotten worse since then. Sand mines now form long strips along both shores of the river between I-45 and I-69. You can’t see them from the ground. They’re hidden by “beauty strips” of trees, berms, and “keep out” signs. So here’s a look from a helicopter I rented on 10.2.19.

I use the word “rape” in a metaphorical context. I am not alleging any illegal acts by mining companies, though I suspect there may be some going on here in terms of illegal discharges. Can you count the leaks?

Other than that, a majority of the state legislature actually encourages what you see below. So does Montgomery County. MoCo gives most of these mines tax breaks in the form of timber exemptions, which the State Comptroller says they should not get; they should be taxed as depleting assets.

Is the West Fork naturally sandy? Yes. That’s a true statement. Is it unnaturally sandy, too? Is sand mining contributing to the loss of Lake Houston capacity? Does it contribute to flooding though massive sediment plugs such as the mouth bar? You be the judge.

From I-69 to I-45 in 72 Photos

The sequence of images below starts at I-69 and goes northwest just past I-45. The first image is at the confluence of the West Fork and Spring Creek. Note the difference between the color of the two. The West Fork splits off to the left. It’s the Lake Houston tributary with virtually all the mines. Below, a small sampling of the destruction that occurs every day in the name of construction…out of sight and out of mind.

I apologize in advance if some of the photos seem repetitive. It’s important to understand how much of the West Fork that mines consume.

Warning: this post contains many photos. WIFI connection, patience, and large screen advised.

Posted by Bob Rehak on 11/3/2019

796 Days since Hurricane Harvey

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