Making of a Flood Fortress: The Kingwood High School Story

At a press conference on 2/22/24, elected and appointed officials from all levels of government gathered to celebrate completion of the new flood barriers that surround the entire campus of Kingwood High School (KHS). They transform the once vulnerable facility into a flood fortress and will protect it in a 500-year flood … plus another three feet!

Yesterday’s event marked the successful completion of more than six years of planning, fund raising, and construction that cost more than $78 million.

The Night Harvey Struck

The ceremony began with an emotional narrative by Humble ISD Superintendent Dr. Elizabeth Fagen. She recounted events from the night that Hurricane Harvey struck in 2017 – 2368 days prior.

They included attempts to organize school buses and evacuate people through rising floodwaters and opening schools to give flood victims places to shelter. She also talked about the difficulty of organizing all this in the dark with spotty power and cell phone services as floodwaters rose and began blocking evacuation routes.

Before it was over, the storm caused the Kingwood High School campus to suffer some of the worst damage in the area. Up to six feet of floodwater contaminated with raw sewage remained elevated for seven days. It caused severe interior damage to all four floors of the school and surrounding campus buildings.

4000 Students at Kingwood High School
KHS during Harvey.

Accelerated Remediation Efforts

Then Fagen discussed the heroic effort to remediate flood damage before the school became uninhabitable. In addition to mold remediation and debris removal, workers removed and replaced:

  • Interior wall coverings
  • Insulation
  • Ceilings
  • Floors
  • Stairwells
  • Crown molding
  • Baseboards
  • Air conditioning
  • Cabinets
  • Plumbing
  • Electrical units
  • Other damaged interior and exterior areas of the 585,000 sq ft. facility. 

“Luckily, we didn’t have to wait for insurance money. The District paid out of pocket to get started immediately. Otherwise, the building would have just been not usable ever again. We immediately started paying for everything to be pumped out and torn out, so that the building could be saved,” she said.

Academic Refugees

Finally, Fagen told about relocating 2,782 students to Summer Creek High School for more than a year, the damage to the District’s Ag Barn, the rush to save animals housed there, and the loss of other district facilities.

It was an emotional tale of struggle, survival, and ultimate triumph. All under an ultimatum from FEMA. They told her, “If the high school floods again, it’s on you.”

Features of the KHS Flood-Protection System

All of this set the stage for PBK architects, who designed the flood-protection system that turned Kingwood High School into a flood fortress. They explained the school’s flood-protection features.

The entire campus is surrounded by three types of barriers:

  • Raisable gates, like draw bridges at all the entries
  • Solid, structural concrete walls with the strength of foundations
  • Three-inch thick glass in heavy-duty, aluminum frames with structural sealant.

The combination is actually in use at the National Archives, according to Fagen. Let’s look at each component.

Raisable Flood Gates

Flood gates, that can be raised from a bottom hinge like a draw bridge, form the first element of the system. When down, students walk over them. When up, they form a watertight seal with the surrounding frame.

The diagram below shows the location of 16 sets, one for each entrance.

The dots represent raisable flood barriers. Lines represent structural concrete walls (see more below).
Flood gate raising at main entrance.
Flood gate fully raised seals with surrounding wall.

There are two ways to raise the gates.

  • One requires only the push of a button.
  • The second is automatic – using water pressure.

As floodwater approaches the doors, it falls through inlets in the floor. The weight of the water acts like a counterbalance that begins elevating the gate. The more the water rises, the higher the gate lifts until it is fully closed.

The ingenious system even has a built-in safety margin to prevent wave action from overtopping the gates.

This passive, self-rising approach ensures the building will seal even if a flood happens in the middle of the night, on a weekend, when personnel can’t reach the school, or when electricity might be knocked out.

Structural Concrete Walls

The entire perimeter of Kingwood High School is now surrounded by a continuous, structural concrete wall – as strong as most foundations. However, the casual observer would never know it. That’s because the concrete is covered with a veneer of more aesthetically pleasing brick.

Dr. Fagen shows off the wall construction, both in the diagram and behind her.

Flood-Proof Glass

Finally, note the glass in the photos above and below. It’s three inches thick and can withstand the pressure of eight feet of water. The glass is seated in heavy-duty aluminum frames with structural sealant.

Congressman Dan Crenshaw addressed the assembled dignitaries and press representatives about the cost and value of such a system.

Cost Versus Value

U.S. Congressman Dan Crenshaw, who helped secure much of the funding for repairs and construction of this system, addressed their cost and value.

Crenshaw said repairs cost almost $56 million. Construction of the flood-protection system cost slightly more than $28 million.

In each case, FEMA paid 90%. The Texas Division of Emergency Management and the Humble ISD paid the remaining 10%.

After insurance reductions of $5.5 million, the total cost came to more than $78 million, said Crenshaw. He joked that, for once, everyone now associated with the school knows where their tax dollars went. Then on a more serious note, he added, “These improvements will actually save taxpayers in the long run.”

“We’re avoiding more costly recoveries in the future by eliminating the damage before it happens.”

Congressman Dan Crenshaw, Texas’ 2nd Congressional District

Maximizing Future Potential

At this point, I’ll add an editorial comment. We also shouldn’t forget the incalculable lifetime costs of displacing 2,782 students and disrupting a critical year of their education. How many didn’t acquire crucial knowledge that would help them excel in college and the workforce because of Harvey? We will never know.

But we won’t have to worry about that in the future, because a community came together and transformed Kingwood High School into a flood fortress to protect its children and their future.

Posted by Bob Rehak on 2/23/24

2369 Days since Hurricane Harvey

Trammell Crow Contractor Pumped Silty Stormwater into Street…Again

On Sunday, 2/18/24 at 12:27 pm, Michelle Chavez photographed a Trammell Crow contractor pumping silty stormwater from a construction site into Kings Park Way near West Lake Houston Parkway. The silty water appeared to be routed through a filter bag.

Contractors commonly use such geo-textile bags to remove oil, grease, sediment, litter and debris from pumped water. But this bag had several gaping holes, undermining its effectiveness. No one appeared to supervise the operation.

Chavez said the water stunk badly. There was so much that it blocked one of the two southbound lanes on Kings Park Way.

Photos of Latest Discharge

See Chavez’ photos and video below.

Trammell Crow contractors pump silty stormwater into street. Looking N along Kings Park Way on 2/18/24 at 12:27 pm.
Same location. Same time. Looking S.
Note holes in filter. Also note time/day stamp on photo.

Here is a 27-second video that puts all the pieces together and shows the construction activity in the background.

A second resident told me that the pumping continued into Sunday night…well after dark. Discharging on Sunday and at night can help avoid those pesky County inspectors.

Previous Discharges

This was not the first time the contractors had been caught on camera. Silty stormwater from the site has run into the street on several occasions in the last few weeks:

After the last visit by Harris County officials, they finally started channelling the water away from Kings Park Way.

Photographed on 2/3/24. Diagonal channel is taking water toward a sediment basin.
Some of the water from the SW corner of the site was channeled into a sediment basin. But by 2/13/24, they had filled in the part of the channel….
By 2/20/24, two days after the pumping filmed by Chavez, they had filled in most of the channel and were starting to install storm sewers.

Most contractors plan for stormwater before it rains. What a mess!

Why Controlling Discharges from Construction Sites is Important

The EPA had this to say about the importance of controlling stormwater discharges from construction sites. “When it rains, stormwater washes over the loose soil on a construction site, along with various materials and products stored outside. As stormwater flows over the site, it can pick up pollutants like sediment, debris, and chemicals from that loose soil and transport them to nearby storm sewer systems or directly into rivers, lakes, or coastal waters.”

In this case, the water goes straight into Lake Houston, the source of drinking water for 2 million people.

County Engineering Notified Again

Harris County Engineering has once again been notified of the latest discharge, though the results of their investigation have not yet been reported.

Remind me never to rent an apartment here.

Posted by Bob Rehak on 2/22/24

2368 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.

CoH Public Works Kicks Off Tree Lane Bridge Rehab Project

City of Houston (COH) Public Works Department held a kick-off meeting with contractors and the Bear Branch Trail Association (BBTA) this morning for the Tree Lane Bridge Rehabilitation Project. Public Works and the contractors outlined plans for the project. They also discussed access through BBTA property and safety protocols.

Chris Bloch (left) and Lee Danner (center) of BBTA met with contractor and Houston Public Works representatives at bridge on 2/21/24.

Construction should begin by mid-March and take approximately 150 days.

Project Scope

The $909,000 project will involve:

  • Creating access areas for equipment
  • Removing all existing concrete under the bridge and along the sidewalls
  • Establishing a 2-foot deep by 32-foot-wide low-flow channel from 20 feet upstream to 20 feet downstream of the bridge
  • Rebuilding wing walls
  • Restoring outfalls for local drainage
  • Restoring the work site and replanting trees.

See the construction plans here.

Safety Warning

Contractors will meet with the Bear Branch Elementary School principal to understand normal drop-off and pick-up times. They will then work around those times to try to minimize traffic interference.

Regardless, the City urged parents to warn children to stay away from the construction zone, which will be on both sides of the bridge. Lots of heavy equipment will be maneuvering in tight spaces with limited visibility near Bear Branch Elementary. Observe all traffic warnings and flag men.

Reason for Project

Embankments under the bridge have degraded significantly in the last 10 years. This is largely because of jetting.

Jetting is caused when water backs up behind a bridge that is too small for the volume of water coming down a stream. Pressure upstream of the bridge forces turbulent water to shoot out the downstream side destroying anything in its way. See six images below taken 2/21/24.

Looking upstream at eastern side of bridge. Jetting has blown out concrete under the bridge.
Damaged storm sewer outfall.
Exposed abutment
Downcutting as floodwater tries to make more room for itself.
Jetting continues to erode a large basin south of the bridge.
Note how narrow creek is upstream (Left). Right = effect of jetting downstream.

It Wasn’t Always This Way

The erosion has started in the last ten years and accelerated with upstream development.

In general, developments increase the time of accumulation of runoff. Compared to a densely developed area, when rain falls on a forest, it trickles its way to the creek. But if it falls on concrete and rooftops, it rushes to the creeks through storm sewers.

For illustration purposes, the graph below shows the actual change along Brays Bayou.

time of accumulation
Change in time of accumulation in Brays Bayou as watershed developed over 85 years.

If development were sufficiently mitigated, post-development runoff would be no higher than pre-development. But given the amount of recent erosion, some development upstream from Tree Lane is likely insufficiently mitigated.

I’ve lived near the Tree Lane Bridge for 40 years. For the first 30, erosion was no problem. Now look at it. Compare the two satellite images below.

In 2014, you could barely see creek.
Same area in 2023.

Chris Bloch, an engineer, says that at the time of Imelda in 2019, the open space under the bridge was 500 square feet. The design approved by COH and Harris County Flood Control District will add approximately 64 square feet in the form of a low-flow channel. Contractors will add that where the stream has already downcut.

If the 500 SF estimate is accurate, another 64 SF would represent a 12.8% increase in the carrying capacity of the channel under the bridge.

Will It Be Enough Conveyance?

This will be the second time in three years that the city has repaired the bridge and its embankments.

The state of the bridge now is worse than it was after Imelda, BEFORE the last repair job. And no storms since Imelda have even came close to Imelda’s magnitude. That means insufficiently mitigated development may have played a role in building flood peaks faster and higher; and undermining the bridge.

So, will 12.8% be enough to eliminate more jetting? Only time will tell. Keep your fingers and toes crossed.

Sign Up for Project Updates

You can sign up for project updates by visiting Houston Public Works’ “Engage Houston” page for this project.

Posted by Bob Rehak on 2/21/24

2367 Days since Hurricane Harvey