Tag Archive for: Woodridge Village

What Went Wrong, Part III: Perry Homes’ Woodridge Village Detention Pond Catastrophe

Note: This is the third in a five part series about What Went Wrong in Woodridge Village that may have contributed to flooding in Elm Grove and North Kingwood Forest. It focuses on Detention Ponds.

Section 7 of the Montgomery County Drainage Criteria Manual cautions, “The introduction of impervious cover and improved runoff conveyance serves in many cases to increase flood peaks quite dramatically over those for existing conditions.” And that’s exactly what happened in Elm Grove and North Kingwood Forest in May and September of this year. Two subdivisions that had never flooded before were inundated with several feet of water from Woodridge Village.

Perry Homes failed to observe numerous regulations in the Drainage Criteria Manual including provisions for:

  • Erosion control measures such as pond linings, revegetation, backslope swales
  • Maintenance roads
  • Increases in downstream flooding
  • Geotechnical reports for detention ponds
  • Drainage of detention ponds

Critically, they also failed to construct all the detention ponds they promised.

Less than a Quarter of Detention Ponds Built

When listing factors that contributed to the flooding, the absence of several promised detention ponds should rank near the top.

  • Before the May flood, only one of five detention ponds (S1) was substantially complete and it provided only 7% of the promised detention capacity.
  • Before the September flood, contractors substantially completed a second detention pond (S2) that added another 16% of promised detention capacity.
  • Since then, no work has been done on additional excavation to protect against flooding.
While clearcutting ALL of the land, Perry Homes installed only PART of the detention.

According to LJA Engineering, Perry Homes was supposed to develop the project in two phases and clearcut only 30 acres in the northern section during Phase 1. However, something changed. Instead, Perry Homes clearcut the entire northern section. And they still haven’t excavated any of the three detention ponds there.

By May 2019, only S1 was substantially complete. By September, S2 was also substantially complete, but overwhelmed.

Had Perry Homes installed all the detention that it promised, the site should have detained a foot of rainfall. But it didn’t. When Imelda came along, it was like trying to pour 100 gallons of water into a 23 gallon jug. Water spilled out of the development into adjacent streets and homes.

Erosion Control Measures Missing for Detention Ponds

Section 7.2.7 of the Montgomery County Drainage Criteria Manual details Erosion Control Measures for Detention Facilities. It states:

“The erosion potential for a detention basin is similar to that of an open channel. For this reason the same types of erosion protection are necessary, including the use of backslope swales and drainage systems (as outlined In SECTION 6), proper revegetation and pond surface lining where necessary. Proper protection must especially be provided at pipe outfalls into the facility, pond outlet structures and overflow spillways where excessive turbulence and velocities will cause erosion.” (See page page 123 of pdf, numbered 113 in doc.)

Revegetation?
Not much grass in S1 (right of the road) or the area that drains into it. All aerial photos below taken on 11/4/2019.
Not much grass on the slopes of S2 either, although Perry Homes did make an ineffective attempt to hydromulch the south (right) border.
No Protection for Overflow Spillway
Perry Homes quality! This spillway from Taylor Gully (right) was supposed to have a grass lining, but still does not. Picture taken 11/4/2019. As of 11/21/19 work still had not started on the lining. Perry Homes has done virtually no work on this pond for three months. However, they did start lining the channel on the right today.
Backslope Interceptor Swales?
The northern edge of the S2 pond has no backslope interceptor swale. As a consequence, water from Taylor Gully at the top of this frame flows over the edge of the pond and erodes it. This may not be a sustainable solution. In the long run, the Gully could erode its way into the pond from the north (top of the frame).

Maintenance Road Missing at Critical Point

Section 7.2.8 talks about Maintenance of Detention Facilities. It states, “A 30-foot wide access and maintenance easement shall be provided around the entire detention pond.” The most critical place in the entire chain of detention ponds, the final outflow culvert into Taylor Gully, has no room for a maintenance road. That’s because when they installed the required backslope interceptor swale, the only place left for it was the maintenance road. That’s planning for you!

S2 has no maintenance easement or road at final outfall into Taylor Gully. The backslope interceptor swale takes up that space.

No Increase in Downstream Flood Levels Allowed

Section 7.3 talks about DETENTION DESIGN PROCEDURES. It clearly lays out the design goal when it says…

No increase in downstream flow rates or flood levels will be allowed.

Further down in this section, the regulations state: “The maximum 100-year water surface elevation in all detention facilities shall be a minimum of 1 foot below the minimum top of bank elevation of the basin.”

Judging from this video shot by Edy and Ricki Cogdill during the May 7th storm, I would say Perry Homes didn’t meet that objective. It reminds me of that slime show on Nickelodeon, but in this case, the innocent bystanders got slimed.

No Geotechnical Report for Groundwater Level at Pond Sites

Section 7.5 discusses GEOTECHNICAL INVESTIGATIONS. It says, “Before initiating final design of a detention pond, a detailed soils investigation by a geotechnical engineer should be undertaken.” Regulations state that the ground water investigation must be “at the proposed site.” Montgomery County has no record of such an investigation or report.

A company called Terracon prepared a Preliminary Geotechnical Report for Perry that addressed issues pertaining to utilities, road pavement and residential foundations. But it makes no mention of detention ponds.

The company took four widely spaced borings around the perimeter of the site that managed to miss all the detention pond locations. Significantly, they missed all the wetlands, too.

Page 17 of Terracon Report. Red lines added to improve visibility of locations.

MoCo Claims It Has No Further Geotechnical Reports

If Perry Homes did additional investigations into ground water on this site, Montgomery County says it doesn’t have them.

If no further investigations were conducted, this could be a fatal flaw affecting the economics of the entire development. Note the presence of standing water in the photo below.

S2 Pond (left), Taylor Gully (center), and area where N3 pond will go (right) all have standing water that will reduce their rated capacity.

The presence of standing water reduces the rated capacity of detention ponds and channels. Only the area above the standing water counts as capacity. Regulations say that these ponds should drain completely (see below).

Thus, S2 likely has lost a third of its designed capacity. N3, when eventually built, could fare worse. Note how close the water is to the surface in the small pond on the right.

If you can’t go deep to get your detention pond capacity, you have to go wide. And that will mean fewer homesites than the 896 they planned. This site might not even make economic sense for building homes.

Problems with Homes Built Over Wetlands

The presence of wetlands in the northern section, which the Terracon report never mentions, would also significantly reduce the site’s suitability for building homes.

This article describes the problems with homes built on wetlands. The title: “Caution: Building in a Wetland Can Be Hazardous to Your House.” A biologist for the US Fish and Wildlife service who investigated filled wetlands in Pennsylvania warned: “Build your house in a wetland, and you’ve got a hobby for the rest of your life. You will be fighting that water forever.” He discusses cracked foundations and also warns, “When wetlands are filled, the water that made them wet has to go somewhere. … the water likely is leaking into formerly dry homes of downstream property owners.”

I’m sure Perry Homes would divulge the presence of former wetlands to the future buyers of homes on this site. It’s the only ethical thing to do and Kathy Perry Britton, CEO, has standards to maintain.

Incomplete Drainage of Detention Ponds

Section 7.6 of the Drainage Criteria Manual addresses GENERAL REQUIREMENTS FOR DETENTION POND CONSTRUCTION. It states:
“A pilot channel shall be provided in detention facilities to insure that proper and complete drainage of the storage facility will occur.” (Emphasis added.)

Complete drainage will likely never occur in S2 and N3 because of the high water table.

To excavate S2 to the required design depth, contractors had to continuously pump water out of it as they worked. It still retains water to this day.

Photo by Jeff Miller on June 2, three days after contractors started digging to the final depth. No surface linings were ever added to this portion of the pond per Section 7.2.7 of the MoCo Drainage Criteria Manual.
Photo taken on June 3 shows contractors were pumping water out of pond as they continued excavating.

If Perry Homes continues its Woodridge Village venture using its current plans, chances are, the company will never provide enough detention capacity for real world conditions. When modeling, their engineers did NOT use the current Atlas-14 rainfall statistics from NOAA.

The new statistics would require 40% more capacity to ensure downstream safety.

Where Does Perry Homes Go from here?

After ignoring regulations, hundreds of homes flooded. And they will flood again. Owning this site is like hanging a millstone around one’s neck. It could drown the entire company in perpetual litigation and debt.

Future Posts in this series will look at:

  • Contradictions in Perry Homes’ Plans
  • The Dirt on Perry Homes’ Soil Test
  • The Floodplain that Wasn’t

Posted by Bob Rehak on 11/21/2019 with help from Jeff Miller

814 Days since Hurricane Harvey and 63 since Imelda

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.

Army Corps to Investigate Potential Wetland Violations on Perry Homes’ Woodridge Village Site

The Army Corps of Engineers is investigating whether Perry Homes, its subsidiaries and contractors violated Section 404 of the federal Clean Water Act. The Corps has regulatory authority for any fill material dumped into waters of the U.S. Those include perennial tributaries and adjacent wetlands.

No Record of Request for Jurisdictional Determination

When developers encounter wetlands, normally they seek a jurisdictional determination from the Corps. They want to ensure they are not violating the Clean Water Act. However, neither Perry Homes nor their subsidiaries (PSWA and Figure Four Partners) apparently sought such a determination. Neither did LJA Engineering, according to Corps records.

In June, a FOIA (Freedom of Information Act) request filed with the Corps of Engineers turned up NO RECORDS of any such request for the Woodridge property. See below.

Army Corps response to June 5, 2019, request for records pertaining to a request for jurisdictional determination on Woodridge Village Wetlands.

The LJA Engineering Drainage Analysis never even mentions wetlands. Wetlands are highly protected because of their ability to filter and retain floodwater, among other things. This multipage article by the USGS describes all the functions of wetlands and legislation affecting them.

Elm Grove Director Requests Investigation

In October, 2019, Beth Guide, a director of the Elm Grove Homeowners Association, went a step further than my FOIA request. She asked the Corps to investigate the legality of the loss of Woodridge Village wetlands. On November 13, 2019, US Congressman Dan Crenshaw received a letter from the Corps stating that the Corps was, in fact, investigating Ms. Guide’s request.

Corps Seeking Access to Property

The Corps is currently contacting Perry Homes (or subsidiary, Figure Four Partners) for access to the site. The Corps characterized the investigation as “an open purported unauthorized activity investigation.”

Colonel Timothy R. Vail, the Corps’ District Commander said, “…we continue to gather all the facts to determine if there is a violation of any of our statutes and if so, determine what might be the appropriate resolution.”

Presence and Importance of Wetlands

Numerous residents near the property noted the wetlands in question. The wetlands also appear in the USGS National Wetlands Inventory.

From the USGS National Wetlands Inventory

For the full text of the letter from the Corps to Congressman Crenshaw, click here.

Ms. Guide believes loss of these wetlands played a role in three floods which struck Elm Grove on May 3, May 7 and September 19 of this year. Before the loss of the wetlands, none of the surrounding neighborhoods ever flooded, according to nearby neighbors. Some of them lived in their homes for more than 30 years.

Typically, wetland vegetation slows down runoff. On the other hand, clearcutting/filling wetlands accelerates runoff. This simple science experiment shows how.

Accelerating runoff reduces the time of accumulation for floodwaters. That means more water reaches ditches faster and at the same time; none is retained upstream. That, in turn, makes floods peak higher.

Posted by Bob Rehak on 11/16/2019

809 Days since Hurricane Harvey and 58 since Imelda

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.

Perry Homes’ Woodridge Village Investment Could Be Costliest Ever

Usually when you make an investment, the worst thing that could happen is that you lose all your principle. But Perry Homes could loose a hundred times more than they paid for Woodridge Village land. That takes special talent.

Out-of-Pocket Costs

The land that Woodridge Village sits on didn’t cost much; much of it was wetlands and many streams converged there. Regardless, a Perry Homes subsidiary, Figure Four Partners, bought the land. Montgomery County Appraisal District values the two main parcels at less than a million dollars. Together they comprise more than 80% of the 268-acre project. (See screen captures below from Montgomery County Appraisal District website.)

Real Costs Could Be 100X Greater

Now let’s look at the real costs to Perry. Just to screw up the land, they paid for:

  • An engineering study that underestimated drainage needs by at least 40%
  • Clearcutting and grading 268 acres
  • Filling in natural drainage
  • Excavating two detention ponds (out of five they promised)
  • Soil tests and a geotechnical report
  • A mile of pavement to the middle of nowhere
  • Two large box culverts
  • Storm drains

Let’s say that cost another five million.

But all of that contributed to the flooding of approximately 200 homes in May and 350 in September. Let’s assume the damage to each home totaled $100,000. That comes to about $55,000,000.

Furniture, appliances, rugs, window coverings and other contents? Let’s assume an average of $40,000. That would total another $22,000,000.

Let’s also assume that 300 cars flooded. Average cost – $30,000. Bingo. $9 million.

Now let’s estimate the reduced marketability of homes that flooded. To do this, let’s assume an average price of $200,000 per home and a 20% reduction. That would cost homeowners $40,000 each in the market value of their homes. That’s another $22,000,000.

And we haven’t even factored in the legal fees of J. Carey Gray, counselor extraordinaire.

If juries rule in favor of the flood victims, that million dollar investment could add up to more than $100 million in potential liabilities…before any penalties for negligence and/or gross negligence kick in.

Corps Now Investigating Wetland Violations

Perry Homes bought wetlands and must have thought that no one would notice when they filled them in. They didn’t even bother to request a jurisdictional determination from the Corps for the wetlands. That reduced costs even more. It’s a proven formula in business; minimize costs to maximize profits.

But perhaps Perry Homes went too far. People did notice. The wetlands that they conveniently ignored fall under the jurisdiction of the Army Corps. And the Corps is now investigating potential violations of Section 404 of the Clean Water Act. That could get expensive all by itself.

Like Building Homes at the End of a Gunnery Range

It just keeps getting worse for Perry. This was kind of like buying land to build homes at the end of a gunnery range. A little risky.

But it’s too late to rethink that decision. No one will ever want to buy a home on this site. It’s less marketable than swampland near Chernobyl.

There’s another rule of thumb in business. When you find yourself in a hole, stop digging. And that’s exactly what Perry has done. They have stopped work on the site for months. Work on detention ponds that would help protect people downstream from future flooding is going undone.

That means the numbers above could balloon with the next big rain. Or a negligence ruling by a jury. Yep, we’re in double Jeopardy now.

Career-Limiting Moves

Whoever made the decision to develop Woodridge Village definitely made a CLM (career-limiting move). At this point, even Perry Homes employees not associated with the decision must worry about their Christmas turkeys. Few careers or companies survive blunders that become case studies for how not to do something.

Eroding Profit Margins

Because of faulty assumptions and corner cutting, Perry Homes put itself between a rock and a hard place. They’ve managed to turn a million dollar investment into a potential $100 million liability. They can’t develop this property profitably now. And they can’t sell it. Who would want to buy this land and inherit the liability every time a storm cloud floats by?

To protect downstream homes from flooding, they would have to expand the detention ponds by at least 40%. And that would eliminate so many homesites that costs could exceed income. I say “at least” because the issue is not just Atlas-14 compliance. While digging the S2 detention pond, contractors hit water that’s not going away.

The S2 Detention Pond has lost about 20-30% of its capacity. The bottom 3-5 feet have been filled with ground water since contractors started digging to the target depth.

That means they can’t achieve their detention goals by going deeper; they’ll have to go wider. And that will cut into marketable land even more.

Toxic for Perry Homes

Let’s face it. When Perry Homes bought this property, Kathy Perry Britton swallowed a poison pill. Woodridge Village now has a toxic reputation that will infect the rest of Perry Homes. No one will ever be able to trust anything Perry Homes says again.

Just imagine how bad this could get for Perry Homes if Montgomery County and the City of Houston really started scrutinizing their permit applications in the future.

But what to do with this land? If you’re Kathy Perry Britton trying to spit shine the legacy of dear old dad, you can’t keep it. And you can’t sell it. You can’t even give it away. No land conservancy organization would take it until the damage done to wetlands and streams was remediated. That could take decades.

The Real Value of Wetlands

However, there are two pieces of good news in this mess.

  • If Perry Homes implodes, it won’t take a lot of investors with it; the company is private.
  • Perry Homes may serve as a lesson to other developers and teach them that the real value of wetlands is their downstream legal costs.

Time To Be Decisive

Just remember, Ms. Britton. Historically, 85% of Houston floods are non-tropical. So if you think you have eight more months to figure this out, think again.

Posted by Bob Rehak on 11/15/2019

808 Days after Hurricane Harvey and 57 after Imelda

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.

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.

Woodridge Village Detention Calculations Off by More Than 40% According to New Standard

Developers in Montgomery County try to avoid building detention ponds by beating the peak. They also have attempted to minimize the amount of detention ponds they must build by beating the clock.

Woodridge Plans Approved One Month Before NOAA Updates Flood Data

A year to the day after the peak of Hurricane Harvey on August 28, LJA Engineering submitted a hydrology report to Montgomery County. A table buried on page 32 of the PDF shows that they based their analysis on a 100-year storm that dropped 12.17 inches of rain in 24 hours.

From Page 2.1 of LJA Hydrology Report Addendum, 8/28/2018 (page 32 of pdf.)

Two weeks earlier, USGS had issued its report on peak streamflows and high water marks for Hurricane Harvey.

At this point, the world knew that flood maps would soon change radically. But the LJA report contains no mention of Harvey, USGS, or NOAA’s new Atlas 14 data. And in fact…

Less than one month after the LJA Engineering hydrology report, on September 27, NOAA issued new rainfall frequency values for Texas. Called Atlas 14, the NOAA analysis established significantly higher rainfall frequency values for this part of Texas.

New updated NOAA Atlas 14 data shows that a hundred-year rain for the Lake Houston area is now defined as 17.3 inches in 24 hours, up from 12.17 inches by the old standards.

NOAA redefined the amount of rainfall it takes to qualify as a 100-year or 1000-year event. They defined the new 100-year rain as 17.3 inches in 24-hours – a 42% increase. That means that to meet new 100-year standards, Perry would have had to increase its detention capacity by 42%. Instead of 271 acre feet, it would have needed 385.

Using Atlas 14 would have reduced the number of salable lots and the economic projections for the development to a substantial degree.

The one flood map in the 59-page LJA Engineering hydrology report shows flood plains magically stopping at the county line.

The one flood map that the LJA hydrology report does include (page 51 of PDF and above) shows flood zones stopping at the county line (the black diagonal) and the boundary of the Perry property (the maroon-bordered polygons). Pretty odd for a site partially covered by wetlands!

National Wetlands Inventory Map shows both sections of Woodridge Village contain wetlands.

Woodridge Plans Approved Even Before LJA Submitted Hydrology Report

Now here’s where it gets even more interesting. City of Houston approved the detention plans on 8/12/18 – two weeks BEFORE the LJA hydrology report on 8/28/18 and only a month BEFORE NOAA released the new Atlas 14 data. Hmmmm! Think they were in a hurry to get these approved? (Note: The approval date for MoCo is unreadable).

Signature block for City of Houston from Woodridge Village detention plans.

Perry Homes played a game of beat the clock and was winning … until May 7, 2019.

Future Flood Risk Remains Even with Planned Detention Ponds

Until now, I have been posting about the lack of detention ponds. Closer analysis reveals that this is only part of the problem. Even if Perry builds the remainder of the detention ponds as planned, they will be insufficient to meet the new NOAA standards and will pose a flood risk to people downstream.

After contributing to two floods in Elm Grove and North Kingwood Forest, the engineers and owners of Woodridge Village surely must realize how dangerous trying to Beat the Clock was.

Forty-two percent of a 100-year flood as defined by the new Atlas-14 data will overflow the banks of the detention ponds and add to the load on Taylor Gully or go into the streets of Elm Grove and North Kingwood Forest.

Facing west. This panoramic drone image by Chris Betz takes in most of the Woodridge Village constructions site. Note the ponding water 3.5 days after a two-inch rain.

This image taken Friday night at Sunset shows how impervious the Woodridge soil is. Water is still ponding three and a half days after a two-inch rain (October 28, 2019).

I wonder if the LJA engineers calculated the runoff coefficient accurately. Given some of the other problems in this report, perhaps an engineer would care to comment on their calculations.

Posted by Bob Rehak on 11/2/2019

795 Days after Hurricane Harvey and 45 after 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.

Two Inches of Rain Should Never Have Caused This

Today, we got two inches of rain between 1:30 and 3:20. That’s according to the closest official gage at US59 and the West Fork. See the graph below. Ben’s Branch came out of its banks almost immediately and nearly flooded St. Martha’s Catholic School and Kids in Action again.

Today’s Rainfall in 10-minute Increments

The closest gage at the West Fork and US59 registered a total of 2.08 inches for the event. In ten-minute increments, it looked like this. Source: HarrisCountyFWS.org.

The Result

St. Martha’s School after two inches of rain in a two hour period. This is what the parking lot of the school looked like 1.5 hours after the rain ended. The floodwaters came from Ben’s Branch which was at a virtual standstill in this area. Water under the Woodland Hills Bridge just south of Northpark Drive barely moved.

St. Martha’s has not yet finished repairs from Imelda. No floodwater actually got in the school today, but it came dangerously close for a rain that was not unusual for this area. The school is at least two feet above the hundred year flood plain and this was a one-year rain at best (see table below).

Across the creek, Heather Jensen at Kids In Action wrote, “We’re currently rebuilding Kids In Action for the second time since May. Can’t stomach a third.” Many people would agree with that!

Expect a Rainfall This Intense at Least Annually

The latest NOAA Atlas-14 rainfall chart for this area shows that we can expect a two-inch rain in two hours at least once a year. If you measure the 10-minute peak, it also works out to a one-year event. Which we’ve had several of this year.

I have lived in Kingwood for 35 years and used to own commercial property near St. Martha’s for twenty years. I have never seen Ben’s Branch do this on a rain like we had today.

During those 35 years, not much has changed along the creek. With few exceptions, the bridges, homes and businesses along this portion of Ben’s Branch have been there the entire time.

New Upstream Development is Major Change

However, new upstream development could be adding to the peaks. The City of Houston confirmed after Imelda that the western tail of Woodridge Village empties into the City storm drains. See two images below.

Photo taken 9/25/2019, looking east. North is left; south is right. The area labeled Woodridge Village in the middle of the shot drains into Ben’s Branch which is out of frame to the right (south).

The storm drains, which also empty Sherwood, in turn empty into Ben’s Branch. See image below.

Looking north along Woodland Hills Drive toward Kingwood Park High School, Sherwood Trails and Woodridge Village. The City says this drain helps empty Woodridge Village.

The shot above is looking north, parallel to Woodland Hills Drive. Below, you can see the reverse angle, looking south. The shot was taken from the second floor of Kids in Action on the north side of the creek. Notice how water from that drain is shooting across the creek, creating more turbulence than the flood itself.

Photo by Heather Jensen of Kids In Action just north of St. Martha’s.

Below St. Martha’s, A Different World

Compare the width of the Ben’s Branch channel in the photos above to the width in the photos below, where the stream goes through a natural area.

Upstream from St. Martha’s, Ben’s Branch is a wide channel. Downstream, shown here, it turns into a narrow, twisting, turning creek. Photo from 9/25/2019, courtesy of St. Martha’s.
Photo from 9/25/2019. Courtesy of St. Martha’s, showing trees encroaching on Ben’s Branch.
In the foreground, you can clearly see evidence of erosion from Imelda. This shot was taken on 9/25/2019. Note the fallen tree in the background. Such blockages create “beaver dams” during heavy rains when other debris catches on them. Photo courtesy of St. Martha’s.

Such obstructions, turns, tangles and narrow beds slow the velocity of the water, causing it to back up. No doubt, these factors play a role in the repetitive flooding, as does upstream development.

Political and Legal Obstructions Complicate Matters

Maintenance responsibilities for this portion of Ben’s Branch are in flux. That may be the kindest way to say it. Nothing has really changed since Harvey.

The Bear Branch Trail Association owns the property according to this deed and the Harris County Appraisal District.

However, from reading the deed, you can see that Friendswood still exercises deed restrictions on the property, especially those applying to drainage. When it comes to saying yea or nay to major changes that affect the character of the greenbelt on either side of Ben’s Branch, Friendswood appears to be in control to this day.

Major Friendswood deed restrictions include:

  • Friendswood reserves for itself multiple easements for drainage. (sec. 3)
  • BBTA must keep the area “healthful” (sec. 8)
  • BBTA may not remove any trees except those that are dead or dying (sec. 8)
  • BBTA may not transfer the land (with a few exceptions that don’t apply to this discussion) (sec. 9)
  • The deed restrictions do not have an expiration date like those for many HOAs.

What Next for Ben’s Branch

Last year, the City reportedly agreed with Harris County Flood Control to assume responsibility for all underground drainage in the county would assume responsibility for all above ground drainage. Since then, the two have been trying to sort out responsibilities.

Harris County Flood Control has sought an easement at least since January from Friendswood and Bear Branch Trail Association. Reportedly, they want to remove some trees, and widen and straighten the channel. However, according to a frustrated Houston City Council Member Dave Martin, no agreement has been reached.

Meanwhile the school for more than 500 children almost flooded for the third time in six months. It’s hard to imagine Kingwood without its largest parochial school or one of its most popular day care/after school facilities. It’s time for

Harris County Flood Control should be concluding a major study of all Kingwood drainage soon…including Ben’s Branch. Let’s hope that helps wake Friendswood up to some new realities.

Posted by Bob Rehak on 10/29/2019

792 Days since Hurricane Harvey and 40 since Imelda

“Perry” Letter: A Good Deal?

Thursday night at the Kingwood Town Hall Meeting, the City discussed a meeting between Perry Homes and city officials including the City Attorney. The subject: How to avoid flooding Elm Grove and North Kingwood Forest again. City officials said they demanded multiple concessions from “Perry Homes.” Two days later, and only hours before the Town Hall meeting, Perry Homes (according to City officials) sent the City a letter outlining what it could do. Mayor Sylvester Turner read portions of the letter to the overflow crowd. It met with mixed reaction. Some people were grateful; others skeptical; still others angry.

Much to his credit, Council Member Dave Martin posted the letter on his FaceBook page. I have reposted it here for your convenience, along with my reactions and those of several other residents.

Page 1 of Response.

Page 2 of response.

Rehak’s Opinions

I was not in the meeting between “Perry” and the City so I cannot comment on the tone of the meeting or how the City presented its “demands.” However, several things struck me about this letter right from the opening paragraph. First of all, it’s not from Perry. That’s why I put Perry in quotes above.

  • The developers expressed how saddened they were by Elm Grove flooding. Yet they are suing the victims. This raises a sincerity issue from the git-go.
  • They say, “Your idea of sharing our collective intellectual capital was a good one, and we appreciate having the City’s input.” Sounds pretty collaborative to me. That’s normally good, but it certainly does not fit with how the City characterized meeting.
  • The law firm representing Perry’s subsidiaries, PSWA and Figure Four Partners, sent the letters, not Perry.
  • Even though the engineering plans for the site call for DETENTION ponds, the lawyer now refers to them as RETENTION ponds. The difference between the two is storage capacity. The latter is like renting a storage shed that’s 80% full…and still paying full price. The City attorney needs to question this.
  • The letter only says that they discussed accelerating the schedule, not that they have accelerated it.
  • The letter lays out timing to construct each detention pond. But it doesn’t say whether they will perform work concurrently or sequentially. If concurrently, the work would take 9+ months. If sequentially, it could take 26 months. They talk about beginning “each project as quickly as the plans can be approved.” This suggests a one-at-a-time approach that could potentially add up to 780 days…assuming there are only “minimal delays” for bidding, approvals, weather, etc.
  • They promised to spend 45 days completing the two southern ponds. Those ponds are already substantially complete.
  • The letter promises to build a berm 2 feet above the 100-year flood elevation between Woodridge Village and Elm Grove. An even higher berm failed during Imelda. Floodwaters overtopped it. Perhaps that’s because Montgomery County bases flood maps on data from the 1980s.
  • They talk about delaying development of homes and streets (impervious cover) until they complete detention ponds. Delaying impervious cover seems like a genuine concession; developers like to build in sections so profit from one can help bankroll the next.
  • The lawyers claim their clients have not yet completed plans and specifications. However, LJA Engineering seemed to have a pretty comprehensive set.
  • The letter provides no guarantees and no penalties for non-compliance or missing target dates.
  • Because Perry has never revealed a construction timetable, we can’t tell whether this schedule beats their original one.

All in all, the timetable in this letter, seemed to take a lot of time for work that they could have completed by now.

Jeff Miller’s Opinions

Jeff Miller is an Elm Grove resident who nearly flooded on May 7th and during Imelda. Most of his neighbors did flood. For months, he has monitored the progress of Woodridge Village construction on a daily basis. He alerted the community when excavation on the site came to a virtual standstill during ideal construction weather.

Miller recently had an “aha” experience when driving by a 5-acre commercial construction site in Kingwood. It had more heavy equipment operating on it than Perry’s 268-acre site did at its peak last summer, he said.

Miller is a retired process engineer. Based on observation of that and other sites, Miller estimated excavation of three more detention ponds would take only about a month if Perry pulled out the stops. Other engineers and construction experts share this opinion.

Josh and Jon Alberson’s Opinions

Both of these brothers have engineering degrees from Georgia Tech. Josh is a chemical engineer and Jon a civil engineer. Jon works on giant construction projects for one of the largest companies in America. The Alberson brothers estimate only 10 days more than Miller. They shared their calculations. The calculations assume a two-step process. Excavate and stack the dirt. Then spread and grade it at a later time.

Basically, they calculated the volume of dirt that needs to be removed. Then they divided that volume by the per-load capacity of heavy equipment. Next, they estimated the time to move one load and return for the next. Using this technique, they could ultimately determine the total time it would take to excavate the three remaining ponds. They consulted with Caterpillar on the capacity of different types of equipment and their recommendations. Follow along to check their math.

Final Capacity of Detention Ponds

N1 + N2 + N3 = 209.9 acre feet = 338,638 cubic yards. (That’s compacted soil before excavation, i.e., bank cubic yards.)

Scraper Capacity per Load
  • Assume typical scraper tractor with 400+ hhp, pulling twin 20 cubic yard (medium size) scrapers.  Then assume a worst case 0.75 load factor for uncompacted soil after excavation (loose cubic yards).
  • Yards per Load = 20 cubic yards per scraper * 2 scrapers per tractor * 0.75 = 32 cubic yards per Load
Total Loads
  • 338,638 cubic yards / 32 cubic yards per load = 10,582 loads
Loads per Tractor per Day
  • Assume tractor cycle time for scraping, moving to pile, and returning to pond is 15 minutes.  This would be a conservative transit time.
  • Then assume the tractor operates 20 hours per day.
    • Lunch – 1 hour per shift = 2 hours per day
    • Maintenance = 1 hour per day
    • Breaks = 2 x 15 minute breaks per shift = 1 hr per day
  • Loads per Day = 20 hours per day * 4 loads per hour = 80 loads per day
Number of Days with 1 Scraper Tractor
  • 10,582 loads / 80 loads per day = 132 days
Number of Days with 4 Scraper Tractors
  • 10,582 loads / (80 loads per day * 4) = 33 days
Assume 20% lost time due to non-productive time, weather, etc.
  • 33 days * 1.2 = 40 days

Said Jon, “Most projects can move 8000 cubic yards per day.”

The two agreed on roughly the same time frame but argued over the optimum combinations of day and shift lengths, pieces of equipment, etc.

That’s just the time to dig the ponds. It assumes they stack the dirt somewhere nearby, then grade and compact it at a later date. Let’s assume that takes another month. But the ponds are excavated!

Now, we’re talking roughly TWO months instead of 9 to 26 months. And beating one or two hurricane seasons.

Note: The LJA Engineering report, upon which these calculations are based, shows at least three different storage capacities for the ponds on the northern section under “ultimate conditions”:

  • Exhibit 2 shows a total of 209.4 acre feet.
  • Table 3 shows a total of 154.2 acre feet.
  • Table 7 and the Conclusion show a total of 163 acre feet.

For the analysis above, the Albersons used the highest volume because it represented the most difficult case. Contractors could excavate the smaller totals, if accurate, in even less time. If 154.2 is accurate, excavation would take only 30 days.

Nancy and Abel Vera’s Opinions

Regardless of how Perry Homes staffs this job, it’s going to take some sweat. That’s the one thing that was not in evidence yesterday or today. Despite the assurances of J. Cary Gray, Attorney at Law, multiple residents reported seeing NO activity on the construction site.

As of Saturday afternoon, Nancy Vera still has seen no activity on the construction site. See the video below taken the day after the Town Hall.

Video taken by Nancy Vera on 10/18/2019, day after Town Hall Meeting

Vera’s husband Abel, manages giant construction projects around the world for one of the world’s largest engineering companies. He agrees that the construction could move much faster.

“If they had the proper equipment and man power, they could move fairly quickly. But they have never done that! They took more than six months to put in this one pond by our house [S2]. And they didn’t even really get going till after the May 7th storm.”

Abel Vera, Resident just south of S2 Detention Pond

A Faster Way?

This video shows the scraper equipment that Alberson and Caterpillar recommended to move large volumes of dirt quickly. The video runs 13 minutes but you will get the idea after a minute or two. These guys collect dirt while rolling.

The Ultimate Scraper Video

Contrast that with what I saw earlier this summer. I watched as a backhoe filled up one dump truck after another. It took several minutes to fill up each truck with multiple scoops. Then each truck took the dirt to its ultimate destination more than a half mile away rather than piling it up near the pond and returning for more dirt. It was a long, slow, dusty procedure with lots of dead time between loads.

Excavation of Woodridge Village S2 Detention Pond took months…one scoop at a time. Photo taken on May 24, 2019.

A Good Deal?

So, does the letter from Counsellor Gray represent a good deal for the residents of Elm Grove. I think not. If Perry Homes really cared about the safety and peace of mind of Elm Grove residents, they could move much faster. The letter commits them to nothing except delaying homes and streets until all detention is in. That’s something. But with most of the surface being hard-packed clay, the threat of rapid runoff remains until they finish all those detention ponds. And someone really needs to proofread that LJA report. It’s scary to think that this whole development could be based on erroneous calculations. I’m surprised Montgomery County approved it.

Posted by Bob Rehak on 10/19/2019 with help from Josh and Jon Alberson, Abel and Nancy Vera, and Jeff Miller

781 Days since Hurricane Harvey and 30 since Imelda

The thoughts 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.

Stunning New Imelda Images Show Stream of Muck Coming Down Shady Maple From Direction of Woodridge Village

Note: If you have pictures of Imelda that you would like to share, please send them in via the Submissions page on this web site. Remember to identify time, date, location and describe what’s happening in the photo.

Where Shady Maple intersects Rustling Elms in Elm Grove, Melanie Bankston and her husband captured some stunning images on the morning of September 19th as Imelda raged across the area. The images show a distinct zebra pattern in the water rushing down the street. Taken as a series, they indicate that:

  • Shady Maple (the street) initially flooded from pure rainwater, not Taylor Gully or Woodridge Village
  • Later, murky brown, sediment-laden water, streamed down the street
  • Woodridge Village did not contain its stormwater as the law mandates.

Because of the way Shady Maple curves, I’ve included this satellite image for orientation purposes. The red arrow indicates the angle of view in the photos. Bankston shot across Shady Maple toward the bridge on Rustling Elms and Taylor Gully.

At 9:37 a.m.

“At 9:37am that we couldn’t clearly see brown water,” said Blankston.

Video at 9:52

At 9:52 a.m. most of the water in the street is still running clear. Note the speed of the trash can as it floats by. Taylor Gully is in the background. You can see it under the crepe myrtle. Also note how the water in the street is rushing toward Taylor Gully, an indication that the water in the gully was lower than in the street.

By 10:37 a.m.

By 10:37 a.m., murky brown water was coming down Shady Maple from the direction of Woodridge Village, where Perry Homes had clearcut 268 acres without installing detention to hold a hundred year storm. Regulations and permits obligated them to do so. Note the distinct color difference between the rainwater that had been rising in the street and the new invading water.
This closer shot was taken seconds later. In it, you can see how the color of muddy water invading the street matches the color of muddy water in Taylor Gully behind the crepe myrtle. At this point in Taylor Gully, the water came almost exclusively from Woodridge Village.

By 11:25

By 11:25 a.m., Taylor Gully had overflowed. The two streams of muddy water merged and started to displace the clearer rainwater in the street.

Likely Path of Water from Woodridge

Erosion signs, silt fences that were pushed over, a trail of damaged homes, and eyewitness statements indicate that water from Woodridge backed up behind the twin culverts at the county line. At a certain point, the detention ponds started overflowing. That’s when water pushed into the streets of North Kingwood Forest and Elm Grove.

In North Kingwood Forest, the same types of evidence suggest that muddy water entered Right Way, then River Rose Court, turned the corner on Creek Manor toward Taylor Gully then turned again down Shady Maple toward Rustling Elms. There it turned another corner toward Taylor Gully, until the Gully came out of its banks.

Path of muddy water through the streets of North Kingwood Forest and Elm Grove toward the Bankston Home, Rustling Elms and Taylor Gully.

Emergency Evacuation for Second Time in Four Months

Keith Stewart who lives on the corner of Shady Maple and Creek Manor evacuated his family in a canoe toward Ford Road in Porter. He says the current coming down River Rose was so fast, he struggled against it.

Keith Stewart family evacuating Elm Grove on 9.19.19. Stewart had just made the turn from Creek Manor, north onto River Rose. He was struggling against the current while taking this shot. Shown in the picture are his wife Jennifer, son Gabriel, and brother-in-law Ambrose Johnson.

The water also overflowed into several surrounding streets, such as Forest Springs. There, Jeff Miller’s security camera picked up the same sudden surge of silty water.

Implications

Aside from the stunning and unusual amateur photography, the content of these images represents yet more evidence that Perry Homes, its subsidiaries and contractors failed to contain stormwater runoff as they were obligated to do by law. Hundreds of families in Elm Grove and North Kingwood Forest paid for that failure.

The Perry gang had only installed about a quarter of the detention on their site before Imelda. The other three quarters of the rain had to go somewhere else and it did.

Posted by Bob Rehak on 10/7/2019

769 Days after Harvey and 18 after Imelda

The thoughts expressed in this post represent my opinions on matters of public interest 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 Construction Near Standstill

Construction progress on the Woodridge Village site has nearly ground to a crawl. After:

…Perry Homes should rename Woodridge Village the Village of the Damned (after the 1960 horror movie). What possesses these people!

Construction Update

The development is reportedly still months behind schedule. That may have something to do with more than 200 lawsuits against the developer.

My last update on Woodridge construction was 18 days ago and little has changed since then according to Elm Grove resident Jeff Miller who tracks construction progress on the site.

The culvert under the street that connects the northern and southern portions of Woodridge Village is now complete. But the street itself has no concrete or curbs. Photo courtesy of Jeff Miller.

According to Miller, “The culvert across Taylor Gully and cement structure around it are complete and ready for the road crew to pave over it.”

The trees that used to separate the northern and southern halves of the development are gone. Photo courtesy of Jeff Miller.

“The clearing continues in the northern section. More trees are laying down and turning brown. I have seen some activity like preliminary marking of the future detention pond N1,” says Miller.

The overflow channel between Taylor Gully and detention pond S2 just north of Village Springs in Elm Grove is being lined with rocks and concrete. Video courtesy of Jeff Miller.
Looking west and panning north. This clip shows that the construction company has hydromulched the berm that separates Woodridge Village from Elm Grove. Video courtesy of Jeff Miller.

“The berm, swale and backslope interceptor structures seem to be complete on the southern border with Elm Grove,” continued Miller. “They have sprayed the slopes with a green fertilizer/seed mixture.”

On the plus side, maybe the grass will help prevent more erosion.

Posted by Bob Rehak with help from Jeff Miller

735 Days since Hurricane Harvey and almost 4 months since the Elm Grove flood

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.

Before-After Shots of Clean-Out: HCFCD Restoring Conveyance of Taylor Gully In Elm Grove

Harris County Flood Control District (HCFCD) is nearing completion of its project to clean out Taylor Gully. The project will restore the ditch’s conveyance through Elm Grove. The ditch had become clogged due, in large part, to erosion from months of clear-cutting and construction activities immediately upstream in the new Woodridge Village development.

After the Flood, but Before the Clean-Out

Below, several shots taken shortly after the May 7th flood.

Erosion on Woodridge Village property. Concrete culvert in background is entrance to Taylor Gully on Harris County side of Montgomery County Line.
Another shot of erosion leading to culvert, visible in upper right.
Looking north at same culvert from Harris County side of county line.
Flood debris carried downstream into Elm Grove portion of Taylor Gully
Shot taken at end of May looking south along Taylor Gully. Three weeks after the May 7 flood.

After the Clean-Out

What a difference some backhoes and bulldozers can make!

Looking south from same area today, but from opposite side of Gully. Photo courtesy of Jeff Miller.
Re-contoured backslope swale with new culvert. Photo courtesy of Jeff Miller.
Newly cleared Taylor Gulley Backslope Swale near the homes that flooded in North Kingwood Forest. Photo courtesy of Jeff Miller.
Brand new backslope interceptor structure and improved swale by HCFCD located just north of Creek Manor where it dead ends into Taylor Gulley. Photo courtesy of Jeff Miller.

These backslope interceptor swales reduce erosion, provide additional floodwater storage, and help prevent floodwaters from impacting structures.

One Month From Statistical Peak of Hurricane Season

Today is one month from the peak of hurricane season – September 11. Hundreds of people in Elm Grove and North Kingwood Forest will have an additional margin of safety thanks to HCFCD’s Taylor Gully project. Despite three months of near-perfect construction weather, Perry Homes’ contractors have only completed two of five planned detention ponds upstream. More on the construction status of Woodridge Village in my next post.

Posted by Bob Rehak on 8/11/2019 with photography from Jeff Miller

712 Days since Hurricane Harvey and 3 months + 4 days since the May 7th flood