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Big Stories to Watch in 2020

As we enter 2020, keep your eyes on these stories.

Elm Grove Lawsuits and Mitigation

In 2019, Elm Grove flooded twice with runoff from the Perry Homes/Woodridge Village development in Montgomery County. Hundreds of homeowners sued Perry Homes’ subsidiaries (PSWA and Figure Four Partners) and their contractors.

On 12/17/19, attorney’s for the plaintiffs filed a fourth amended petition. Since the original filing, plaintiffs have named Double Oak Construction and Texasite LLC as additional defendants.

The judge set a jury trial date for July 13, 2020. To date, Perry Homes has done nothing to reduce the threat of flooding from their job site.

The 268-acres clear-cut acres that contributed to Elm Grove Flooding.

That brings us to the subject of mitigation.

What can be done to restore the safety of residents?

Perry Homes has demonstrated no interest in reducing the threat to downstream flood victims.

Protecting homeowners will require massive intervention from an outside source. But who? And how?

Harris County Bond Fund Mitigation Projects

In 2019, Harris County Flood Control began work on 146 of 239 of the projects identified in their $2.5 billion flood bond.

Many of those projects required studies and partners. Three affecting the Lake Houston Area are:

Many projects could actually enter the construction phase next year.

Recommendations from each study should come out in 2020. Then many more projects will get underway.

Upstream Development

In 2019, we saw what upstream development did to homes in Elm Grove and North Kingwood Forest bordering Taylor Gully.

I recently learned of two new developments in the Ben’s Branch watershed.

  • A developer intends to build 18 acres of apartments where the woods adjacent to the new St. Martha Church now stand.
  • Another developer intends to build hundreds of homes on tiny lots on an 80-acre site just north of St. Martha’s.

These two projects represent dozens of others gobbling up farm and forest land in southeast Montgomery County.

This drainage ditch feeds into Ben’s Branch at Northpark Drive. The 18 acres of trees on the other side of the ditch could soon become apartments.

Businesses such as the St. Martha School and Kids in Action already flooded twice this year. So did dozens of homes along Ben’s Branch.

Additional upstream development has the potential to make flooding even worse. This is like death by a thousand cuts. Residents just don’t have the time or energy to monitor each development to ensure that owners follow rules and regulations for wetlands, floodplains, drainage, etc. Neither evidently does Montgomery County. Which brings us to…

Montgomery County Standards and Enforcement

Montgomery County competes for development by touting its lack of regulations. That’s a huge problem for downstream residents.

  • Montgomery County still bases flood maps on data from the 1980s.
  • Large parts of the county remain unmapped for flood hazards.
  • The County last updated its Drainage Criteria Manual in 1989.
  • Developers ignore many provisions within it.
  • County Commissioners voted to leave loopholes open that allow developers to avoid building detention ponds.
  • The County even paid an engineering company to investigate itself for its role in the Elm Grove Disaster.

You get the idea. If you thought some benign government entity watched over new developments to protect downstream residents, think again. Below you can see the 80-acre site I mentioned above.

Source: USGS National Wetlands Inventory.

Note how it was covered in wetlands. Developers did not ask permission from the Corps to remove them. They just decided on their own that they didn’t need to ask.

Below, you can see how virtually half the site is in a flood zone or floodway.

Source: FEMA’s national flood hazard layer viewer. Brown = 500 year flood plain, aqua = 100 year, cross-hatched equals floodway.

Here’s how it looks in Google Earth. Developers have already cleared the site.

Developers intend to build high-density homes in the floodplains. They will also build their detention pond in the floodway. Those hazard areas will likely expand when and if the County incorporates new Atlas-14 data into their flood maps.

Layout for Brooklyn Trails development in Montgomery County

None of this seems to bother the leadership of Montgomery County. And that’s a bigger problem than any one development.

In 2020, expect more focus on the decision-making process and decision makers who have created a permissive culture of indifference to flooding problems.

Sand Mines

Sand mines operate so closely to the San Jacinto that their walls frequently break and pour polluted process water into the drinking water for 2 million people. If they get caught, they pay a small fine and continue operating with impunity.

Left: Liberty Materials Mine in Conroe that undercut five pipelines carrying highly volatile liquids. Center: Triple PG mine in Porter where erosion during Imelda exposed one natural gas line and threatens 5 more HVL pipelines. Right: Another Liberty Materials mine that allegedly dumped 56 million gallons of white goop into the West Fork.

Upstream Detention

During Harvey, the release of 80,000 cubic feet per second from Lake Conroe added to downstream flooding. The goal: to find enough upstream detention capacity to help offset future releases. The San Jacinto River Basin Study will examine that possibility. It’s unlikely that one reservoir will provide enough capacity. However, multiple smaller reservoirs may.

Peak flow map during Harvey.

The study partners will release their results in the second half of 2020. Land acquisition and construction could take several additional years.

Dredging

Dredging is another essential element of flood mitigation on the West Fork of the San Jacinto. Sand buildup near the mouth of the river has created a giant sediment dam. The Army Corps removed three feet in a dredging effort that ended on Labor Day. But much remains.

Luckily, State Representative Dan Huberty sponsored legislation that allocated another $30 million. The Harris County Flood Bond allocated $10 million. The City of Houston allocated $6 million. Plus two more grant requests are still pending that could increase the total even more. And a disposal site for the material has already been permitted.

Mouth Bar of the West Fork. Photo taken 12/3/2019.

Last week, Harris County commissioners voted to proceed with additional dredging. Project managers are studying the most cost effective ways to proceed. We should see more dredging soon.

This money could also be used on the growing mouth bar of the East Fork.

State Highway 99 Extension

The extension of the Grand Parkway (State Highway 99) east and south to I-10 will open up vast new expanses of forest and farmland to high density development. The biggest threat will be to the East Fork watershed as construction moves through southeast Montgomery County and the northeast tip of Harris County into Liberty County.

Eastward clearing for SH99 has reached Caney Creek near Lake Houston Park.

Those are my predictions for the biggest stories of 2020. There’s a lot of good news in the forecast and much to remain vigilant about. Life seems to be a constant struggle between those who would increase and decrease our margin of safety when it comes to flooding.

Posted on 12/21/2019 by Bob Rehak

844 Days after 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.

Lake Conroe Lowering Benefits MoCo Residents, Too; More Than 1100 Flooded on West Fork During Harvey

Lake Conroe residents organizing opposition to the SJRA’s lake lowering policy have found it easy to “blame” Kingwood for their inconvenience. Kingwood is an affluent community in another county. But the Lake Conroe people ignore more than 1100 homes between Kingwood and Lake Conroe in Montgomery County (MoCo) that also flooded.

The lake lowering reduces downstream flood risk by creating extra capacity within the lake during months with the heaviest rainfall. It is a temporary measure until flood mitigation measures can be completed that help protect the Lake Houston Area.

ESRI GIS Database Shows Counts of Damaged MoCo Homes

ESRI operates a Montgomery County GIS (geographic information system) database called the Harvey Story Map. (Unfortunately, this may not work with all versions of Safari. Try Chrome if you have trouble.) Clicking on Section 12 shows the location of homes that flooded during Harvey in MoCo.

As you to zoom, you can see counts of flooded structures within the visible area. For instance, around Lake Conroe, 292 homes flooded during Harvey. The map below shows the location of those homes.

292 homes flooded on Lake Conroe during Harvey. Lake lowering gives them an extra buffer against flooding.

If you continue to zoom in, you can even see how individual houses fared in other floods as well.

Below are six screen captures that give you a sampling of what you will find. This first area is just below the Lake Conroe dam where 30 homes flooded during Harvey.

Below is River Plantation, just downstream from I-45. Put your water wings on, Bucko! The count here: 527.

Here are four more subdivisions farther downstream.

The West Fork subdivisions shown above had 1159 flooded structures during Harvey. But more homes flooded than in these six images. For starters, there were the 298 homes around Lake Conroe itself.

So, to the 4,484 homes that flooded in Kingwood, Humble and Atascocita on the West Fork, add these and more.

I’m not sure how many people have waterfront lots on Lake Conroe, but is their boating convenience really worth risking the possibility of flooding even a subset of these homes again?

Posted by Bob Rehak on 11/24/2019

817 Days after Hurricane Harvey