Tag Archive for: excavation

Woodridge Village Excavation Slows

During September, Sprint Sand & Clay excavated another 5,698 cubic yards of material from Woodridge Village, down slightly from the previous month. However, that brought the total to date up to 150,724 cubic yards – a nice milestone.

Attempted development of the property contributed to the flooding of neighboring properties twice in 2019 during May and September.

Background of Project

Sprint’s excavation will create a sixth stormwater detention basin on the former Perry Homes property purchased by Harris County Flood Control District (HCFCD) and the City of Houston in 2021.

Sprint began excavation in January of 2022 under an Excavation and Removal Contract (E&R). The E&R contract gives Sprint the right to remove up to 500,000 cubic yards of material for just $1,000. Sprint then makes its money back by selling the dirt at market rates.

Where Things Stand

To date, here’s where things stand in relation to possible goals:

Acre Feet of Stormwater Detention% of Atlas-14 Requirement% of Ultimate
Site Had When Purchased from Perry Homes27170%47%
Has as of 10/3/23364.494.6%62.8%
Atlas 14 Requires385100%66%
If Sprint Excavates All 500K Cubic Yards580150%100%
As of 10/3/23

The rate of excavation slowed in September compared to August. During August Sprint excavated 10,353 cubic yards – almost twice as much.

E&R contracts often fluctuate like this depending on home- and road-building activity nearby. Regardless, Sprint still exceeded its contract’s monthly minimum of 5,000 cubic yards.

Before/After Pictures For September

The first two photos below show the extent of excavation at the beginning and end of September.

Woodridge Village E&R activity
Looking NE from SW Corner. Beginning of September.
End of September 2023

I see no dramatic changes. They did, however, nibble away at the edges in the top left corner, where the tire tracks lead to. Here’s a closeup of that area.

NW limit of excavation as of September 30, 2023
Reverse angle looking SW. Notice removal of surface layer in the lower right.
Entry view, 9/30/23

Rain always slows construction activity and it may have played a role here. The pool of water above was one third this size at the start of the month.

5,698 cubic yards of material for September equals 3.5 acre feet. At that rate, the detention basin will not reach Atlas-14 requirements for another 5-6 months. It appears unlikely at this point that Sprint will meet Atlas-14 requirements by the end of the year – unless Sprint really sprints.

No Engineering Report Yet

At the start of the project, HCFCD planned to go beyond Atlas 14 to accommodate possible future increases in rainfall requirements and upstream growth. That would provide an extra margin of safety for people in the area.

HCFCD still has not released the final engineering report yet for Woodridge Village and Taylor Gully. So we don’t know yet how large this detention basin will be, i.e., beyond Atlas 14.

That final engineering report will also determine the final shape of the basin and its connectivity to other drainage on the site.

Posted by Bob Rehak on 10/3/23

2226 Days since Hurricane Harvey

Woodridge Village Excavation Reached 92% of Atlas-14 Requirements in June

At the end of June, stormwater detention basin excavation on Harris County Flood Control District’s (HCFCD) Woodridge Village property reached 92% of Atlas-14 requirements. When HCFCD bought the property from Perry Homes in 2021, it had only 70% of the required detention capacity under Atlas 14.

Atlas-14 defines the current standard for safely containing a 100-year rainfall. The lack of detention basin capacity contributed to the flooding of hundreds of homes along Taylor Gully twice in 2019, after Perry contractors clearcut the property.

HCFCD and City of Houston purchased the property from Perry in March 2021. Excavation of additional detention capacity started in January 2022.

June/July Photos Show Progress

The first photo below was taken at the beginning of June 2023 so you can see how much progress has been made in the last month.

Looking ENEExtent of Excavation on June 4, 2023

The second shows the site at the beginning of July 2023. The primary changes seem to be additional depth and length.

July 1, 2023 photo shows additional depth at far end of project.

HCFCD spokesperson Amy Crouser said that, “Essentially, the contractor is free to excavate where they want within the provided footprint.”

Rough layout for new Woodridge basin.
Green area indicates rough outline of new basin.

Where Does Woodridge Village Excavation Go From Here?

HCFCD’s Excavation and Removal contract with Sprint Sand & Clay calls for excavating up to 500,000 cubic yards. Sprint excavated approximately another 8,000 cubic yards in June. That equals approximately 5 acre feet.

If Sprint keeps excavating at that rate, the table below shows that it could reach Atlas 14 requirements by the end of this year.

However, Sprint’s contract calls for excavating UP TO 500,000 cubic yards. Any excavation beyond Atlas-14 needs would create a safety hedge against future needs should they increase. 

NOAA is already working on updating the Atlas 14 requirements and should release Atlas 15 before the end of this decade.

Here’s how all that looks in a table.

Acre Feet of Stormwater Detention% of Atlas-14 Requirement% of Ultimate
Site Had When Purchased from Perry Homes27170%47%
Has as of 7/1/2335392%61%
Atlas 14 Requires385100%66%
If Sprint Excavates All 500K Cubic Feet580150%100%
Calculations based on original construction plans, HCFCD monthly reports, Atlas-14 Requirements and Sprint contract.
Sprint could excavate down to or even slightly past the small grove of trees in the top center. Photo taken July 1, 2023.

Sprint will make only $1,000 from its Woodridge Village excavation contract with HCFCD, but will make its profit by selling the dirt at market rates. It’s a good deal for taxpayers, but carries some uncertainty with it.

If the demand for dirt dries up and excavation slows, HCFCD and Sprint could modify the E&R contract to complete a smaller detention basin sooner. But I assume it would still meet Atlas 14 requirements at a minimum.

But simply excavating the dirt isn’t the end of the job. Harris County still needs to slope the sides, plant grass, and tie the new basin into the site’s existing stormwater-detention-basin network. Engineers are reportedly working on plans for all that, according to HCFCD.

Posted by Bob Rehak on 7/1/2023

2132 Days since Hurricane Harvey

Woodridge Village Excavation Surpasses 100,000 Cubic Yards

In the four weeks since my last update, Harris County Flood Control District’s (HCFCD) contractor has excavated another 11,000 cubic yards of dirt from Woodridge Village. That means Sprint Sand and Clay has removed a total of 104,000 cubic yards since it started work under its Excavation and Removal Contract a little more than a year ago.

Sprint is removing the dirt from what will become a sixth stormwater detention basin on the former Perry Homes site. The lack of adequate detention capacity on the site contributed to flooding hundreds of homes in Kingwood twice back in 2019, before HCFCD purchased the property.

New Excavation Already Second Largest on Site

Already, at 62 acre feet, the new basin ranks as the second largest stormwater detention basin on the 268-acre site. Woodridge Village’s five original basins had the following capacities:

  • N1 = 13.2 acre feet
  • N2 = 154.7 acre feet
  • N3 = 42 acre feet
  • S1 = 18.6 acre feet
  • S2 = 42.5 acre feet

The new detention basin could more than double capacity on the site. Ultimately, it will exceed Atlas 14 requirements.

Here’s where the original five are located.

Locations and sizes of first five stormwater detention basins shown in blue.

The new basin will go between N2 and S1.

Woodridge Village Excavation and Removal
Location of new basin outlined in red.

Progress by the Numbers

The 11,000 cubic yards excavated in the last 28 days averages 2,750 cubic yards per week. That’s an increase of 220 cubic yards per week compared to the previous month. It’s also 1,000 cubic yards per week more than the weekly average since the start of the contract.

The current monthly rate more than doubles the minimum required under Sprint’s contract.

The excavation of 100,000 cubic yards marks yet another milestone. Sprint has now removed more than 20% of the 500,000 cubic yards allowed under the contract.

February vs. March Photos

To get a feeling for just how much 11,000 cubic yards is, compare these photos taken at the ends of February and March.

Extent of excavation for new Woodridge Village Detention Basin as of 3/5/23
End of February
End of March: excavation stretches much farther into the distance.

A Head Start on Construction

In December 2022, HCFCD revealed the results of its analysis of alternatives to reduce flooding adjacent to Woodridge and Taylor Gully. HCFCD is now working on finalizing those plans.

Excavation and removal contracts give HCFCD a head start on construction while engineers finish plans. This compresses the timetable.

The contract also saves taxpayers money. It gives Sprint the right to remove up to 500,000 cubic yards for a grand total of only $1000. Sprint makes its money by selling the dirt at market rates to home- and road builders. The only restriction: the dirt can’t be placed in the floodplain.

Posted by Bob Rehak on 4/4/2023

2044 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.

Progress Report New Woodridge Village Floodwater Detention Basin

A new floodwater detention basin that will ultimately more than double the capacity of Woodridge Village is expanding slowly but steadily. To date, 33,159 cubic yards have been excavated! The pictures below show progress since the start of work in late January.

Photos showing Progress

Harris County Flood Control District (HCFCD) announced the project on 11/24/2021. Excavation started on 1/27/22.

beginning of Woodridge Village excavation
First truckloads of of excavated material leave the southwest corner of the site on 1/27/22. Looking SW.
Wider shot taken on same day looking NE looking in opposite direction. The new basin will eventually expand to cover most of the area within the road, tree-line on the left, and the ditch that bisects the property from left to right.
Photo taken on 2/14/22 shows the excavation expanding. Looking SW.
Four days later. 2/18/22. Looking SW toward entrance.
Another three days later, on 2/21/22.
3/22/22 after a 2.26 inch rain.
3/28/22. Looking NE.
4/17/22. Looking SW.
Basin will ultimately expand to green boundary.

About Vendor’s Contract

The stormwater detention basin still has a long way to go before it reaches its ultimate size. HCFCD is excavating it under the terms of an E&R (Excavation and Removal) contract with Sprint Sand and Clay.

Sprint has agreed to remove up to 500,000 Cubic Yards of dirt for only $1,000. However, it has the right to sell the dirt at market rates to make a profit. But the dirt can only elevate structures outside of current floodplains.

Three Months Into Contract, Beating the Minimums

When Perry Homes finished its planned floodwater detention basins, it had enough capacity to hold a hundred year rain as defined by pre-Atlas-14 standards. But capacity fell 40% short of Atlas-14 requirements.

The addition of the new detention basin should take capacity well beyond Atlas-14 requirements and create a safety margin that accommodates additional upstream development.

Excavation under an E&R contract can have ups and downs. When construction booms, excavation moves along quickly. But when construction slows, excavation can, too. However, the contract does have minimum excavation requirement of 10,000 cubic yards per month written into it.

At 36,000 cubic yards after roughly 2.5 months, Sprint exceeds the minimum. But if that rate continues, it could take another four years to reach 500,000 cubic yards.

At some point, the county may choose to step in and pay market rates for excavation to speed things up. But until then, every truckload hauled out of Woodridge Village by Sprint will reduce the ultimate cost.

Posted by Bob Rehak on 4/18/2022

1693 Days after Hurricane Harvey

Excavation of Additional Woodridge Village Detention Pond to Begin Soon

Here’s something to give thanks for on Thanksgiving. Harris County Flood Control District (HCFCD) announced Wednesday, 11/24/21, that Sprint Sand & Clay could begin excavation of another large detention pond on the Woodridge Village property as early as November 29. Lack of detention pond capacity on the property while it was being cleared contributed to flooding hundreds of homes in Elm Grove and North Kingwood Forest twice in 2019.

Homeowners evacuating during Imelda.

Not Enough Detention Pond Capacity Existed to Meet Atlas-14 Requirements

Even after Perry Homes finished building the detention ponds in its plans, the volume still fell about 40% short of the capacity needed to meet Atlas-14 requirements.

Thus, the twice-flooded homeowners have been living in constant fear since then of every storm that passes overhead. PTSD caused some to postpone home restoration or even move away. So this should come as great news to the community.

HCFCD purchased the Woodridge Village property earlier this year. Harris County Commissioners then approved a contract for excavation in July. The excavation could be sporadic, however, because of the nature of the contract.

Sprint Sand & Clay will excavate material as needed under the terms of an HCFCD E&R contract. E&R stands for Excavation & Removal. HCFCD will pay Sprint just $1000 to excavate 500,000 cubic yards. Sprint then has the right to resell the dirt to developers, contractors and road builders at market rates.

The 500,000 cubic yards should more than compensate for the 40% shortfall of detention on the Woodridge site.

Creating Extra Capacity

When Perry left the site, it had constructed 271 acre feet of detention. The site needed another 108.4 acre feet of detention pond capacity to meet Atlas-14 requirements, but will get 310 (the number of acre feet in 500,000 cubic yards). That almost triples the required additional volume and more than doubles the current capacity…all for $1000.

That extra capacity will create a margin of safety for residents in case expected rainfall rates increase again in the future.

It will also create a buffer against future development. For instance, it should help those downstream on Taylor Gully where it joins White Oak Creek. Rapid development continues upstream on White Oak Creek.

Nature of Contract Will Lower Cost, but Could Extend Completion Date

The nature of an E&R contract benefits taxpayers from a cost standpoint. It’s like getting free help. However, there’s also a potential hitch; demand fluctuation could delay the dirt’s removal. The contract obligates Sprint to remove a minimum of 5,000 cubic yards per month. But Sprint can average that, taking 10,000 cubic yards one month and none the next.

Thus, Elm Grove and North Kingwood Forest residents might see furious excavation activity one month and none the next.

Regardless, HCFCD checks progress periodically with drones. And if Sprint looks like it is not complying, HCFCD has the right to terminate the contract. Otherwise, removal of the dirt could take up to three years.

The contract gives Sprint the right to sell the dirt anywhere with one condition. The ultimate placement must be outside any known floodplain – including the 500-year/0.02% annual chance floodplain.

This is the first time HCFCD has signed such a contract for work outside of Harris County. Woodridge Village sits in Montgomery County immediately north of the county line.

HCFCD started using E&R contracts all over Harris County long before the Bond. It was a way to show progress on detention basins that HCFCD had no money to build. The Cutten Road, Lauder Road, and Aldine-Westfield basins on Greens Bayou all started with E&R contracts.

Pond Will Go in Southern Section of Woodridge

The detention pond excavation will take place close to Sherwood Trails and Elm Grove to help intercept water coming off the steep northern portion of the site. See the green area below.

The new pond will also border the road that Perry built into the site. That will help facilitate removal of the dirt. See the photo below.

Looking East. Woodridge Village as of November 11, 2021. The new detention pond will go in the big empty area between the road and ditch which leads from upper left to top middle. Sherwood Trails, Elm Grove and North Kingwood Forest are inside the trees on the right.

Construction Must Observe Stormwater Quality Requirements

HCFCD emphasized that all normal stormwater quality precautions will remain in effect. Rain that falls during excavation will be pumped into one of the site’s existing detention ponds (on the right in the photo above) to keep sediment from migrating downstream. That’s important because HCFCD just finished excavating Taylor Gully to restore its conveyance. No one wants to see it get plugged up again.

Site Closed During Construction

The construction work involves heavy machinery. Physical barriers and safety signage alerting visitors will be placed at access points. Residents should follow all posted signs and remain clear of the construction zone.

Trucks Will Work Around High-School Schedule

HCFCD has coordinated the contractor’s work schedule with administrators at Kingwood Park High School and Humble ISD to avoid arrival and departure times at the high school.

For More Info

If you’re tracking the progress of this on the HCFCD website, look for “Excavation and Removal Project at Former Woodridge Property” under Kingwood Information in the SAN JACINTO Watershed:

  • Project ID: G503-06-00-E002
  • Bond ID: Z-02

HCFCD also maintains Facebook and Twitter pages.

The City of Houston purchased the northern 70 acres of the site for a wastewater treatment facility. But the fate of the rest of site has not yet been decided. Community groups have reportedly been lobbying to turn the area into a wooded park with trails. A decision could come on that in the next few months.

HCFCD officials emphasized that the final dimensions of the pond could change as excavation proceeds. But dimensions should be determined long before Sprint finishes excavation.

Posted by Bob Rehak on 11/25/2021

1549 Days since Hurricane Harvey

Commissioners Vote Tuesday on Contract for Woodridge Village Detention Pond Excavation

Tuesday, 7.20.21, Harris County Commissioners will vote on a contract with Sprint Sand & Clay for excavation of a Woodridge Village detention basin. Item #21-3394 on the agenda is only for $1000, but it gives the contractor the right to enter the site and begin removing up to 500,000 cubic yards of dirt (at no cost to HCFCD) which it can then sell.

Backup provided to commissioners states that “This benefits the District because excavation and removal is always the highest cost of any stormwater detention basin that is constructed.”

Details of Proposed Contract

Here is the full text of the proposed agreement. Highlights include:

  • Amount of excavation TBD – somewhere between 20,000 and 500,000 cubic yards, depending on plans that HCFCD will deliver to the contractor based on the outcome on an engineering study currently underway.
  • The contractor must properly dispose of the spoils, which it is allowed to sell to make its money on the contract.
  • Contractor is liable for any materials that are disposed of improperly, i.e., within Base Flood Elevation or the 500-year flood plain and must identify all disposal locations.
  • Time allowed: 3 years.
  • Termination of contract possible if contractor fails to excavate a minimum average of 5,000 cubic yards every month.
  • Contractor responsible for environmental mitigation if necessary, excluding wetlands.
  • The contractor must provide an approved Stormwater Pollution Prevention Plan and abide by it.

The contract outline contains the map above but does not specify the exact size, depth or location of the proposed work within the outlined area – just that it will occur in Montgomery County. Engineers will supply additional details at a later date.

Making up for the 60% Solution

Assuming commissioners approve this, it is good news for the people who live who live in Elm Grove and North Kingwood Forest – indeed, for everyone who lives along Taylor Gully. The detention ponds installed by Perry Homes before they sold the land to Harris County were based on old rainfall statistics and will only hold about 60% of a new 100-year rain defined in Atlas-14.

Looking SE across Woodridge Village toward Elm Grove and North Kingwood Forest, areas where hundreds of homes flooded badly in 2019 twice. Photo taken May 26, 2021.

Sprint Sand and Clay is a regular contractor for HCFCD. Currently, the company is excavating the massive Cutten Detention Basin near 290, Beltway 8 and Cutten Road.

Posted by Bob Rehak on 7/20/21

1421 Days since Hurricane Harvey

Perry Contractors Now Focusing on Finish Work for Detention Ponds

Perry Homes’ current contractors have excavated 3X more detention pond volume in ten weeks than the previous contractors did in virtually two years. During this past week, they finished excavating three ponds on the northern section of Woodridge Village. Together, they comprise 77% of the total detention volume for the whole site.

Excavation Done, but Finish Work Remains

That doesn’t mean they’re totally done with the ponds. Recent aerial photos show that they still have much finish work to do. That includes:

  • Shaping the sides
  • Creating backslope swales
  • Installing pipes to funnel water from the swales into the ponds and channels
  • Ensuring water can flow out of Adams Oaks in Porter on the west side of the subdivision into Taylor Gully as it previously did
  • Creating concrete “pilot channels” in the center of the ponds and larger channels
  • Planting grass along the sides of the slopes to reduce erosion
  • Installing outflow control in several places to hold back floodwaters
  • Building maintenance roads around the ponds

Elm Grove resident Jeff Miller, who monitors the progress of construction daily, says crews are already hard at work on many of those tasks.

Ponds NOT Expanded Beyond Initial Plans

Miller has compared the width and depth of ponds to the initial plans and verified that the ponds are being built to original specifications. Since the ponds were designed to meet pre-Atlas 14 rainfall requirements, that means the site will still hold 30-40% less runoff than needed to meet current regulations.

Still, surrounding residents in Porter, North Kingwood Forest and Elm Grove who flooded twice last year will find three large ponds on the northern section a welcome addition. They provide some measure of extra protection. Residents will have four times more upstream detention volume than they had during Imelda.

Racing Against Risk

With the peak of hurricane season now less than two months away, Perry Homes is in a race against risk. The company may regret the six months of virtual inactivity between the completion of pond S2 and the start of work on ponds N1, N2, and N3 in early April.

The faster pace of current construction puts pressure on Harris County and the City of Houston to complete an offer if an offer will be made. Elm Grove residents lobbied the City and County to purchase the property and build a regional flood detention facility. They center would also help protect downstream residents on the East Fork and Lake Houston.

However, at a Kingwood Town Hall Meeting in February, Mayor Pro Tem Dave Martin announced that the City would not participate in a deal. He said it was the County’s responsibility.

In April, the County announced that it would consider purchasing the land if the City contributed land in lieu of cash to cover half the purchase price.

Then in May, the County increased its demands. The County now wants the City to contribute land in lieu of cash to cover half the purchase AND construction costs for creating additional detention.

County and City Clamp Down on Communications

Since then, the County has clamped down on communications regarding this subject. Rumors suggest that all parties are still trying to make a deal happen. But the County has denied all FOIA requests and referred them to the Texas Attorney General for a ruling on their denials. That often happens when negotiations are in progress, according to a knowledgeable source.

What Happens Next?

At the contractor’s current rate of progress, it’s entirely possible that contractors will complete all work on detention ponds in July.

The City and County blew through a May 15 deadline that Perry put on the deal. But a “For Sale” sign at the Woodland Hills entrance remains on the property.

With approximately $14 million dollars invested in the property, with hurricane season here, with lawsuits pending, and knowing that the amount of detention is insufficient to hold a 100-year rain, Kathy Perry must be sweating bombshells.

Ms. Perry may be hoping for a City/County offer, but she can’t be counting on one. If she were, she could have sold the dirt coming out of those detention ponds. Instead, however, she’s building up land elsewhere on the site to keep her options open and develop the site if a deal falls through.

That dirt will have to be moved again at taxpayer expense if the county builds additional detention ponds.

Pictures of Site as of 6/19/2020

Here’s what the site looked like as of 6/19/2020.

Looking NW from over Taylor Gully toward Pond N2, the largest on the property.
The connecting channel between N1 at the top of the frame and N2 along the western edge of the property has been excavated. Note the pilot channel that contractors have started in the distance.
At Mace Street in Porter, contractors created a concrete face for the twin culverts on the upstream side, but not yet on the downstream side. Note the earthen dam holding water back while contractors complete the pilot channel running off the bottom of the frame.
Above Mace Street, contractors are still putting in pipes between the channel and backslope swales.
The Webb street entrance to the site has been removed to connect N1 (out of frame on the top) with N2 (out of frame on the lower left).
Looking SE at N1.
Looking South at N3, which runs down the eastern edge of the property.
More pipes are being put in to channel water from backslope swales to the pond so water won’t erode the face of the pond. Not the rills already cut in the dirt.
Looking SE. The southern half of N3 where it connects with Taylor Gully in the upper right.
N3’s connection to Taylor Gully is now wide open. It’s not clear how this connection will be completed to release the water at a slow controlled rate.
The two culverts under the bridge over Taylor Gully should slow the water from N2 (upper right) and N1 (out of frame) down.

Need for Grass if Deal Not Reached Quickly

Note how the grass on the southern side of the gully has all died. That raises a question. If Perry, the City and County do not complete a purchase agreement soon, will Perry plant grass on the northern section to slow runoff. Right now, it’s all hard-packed dirt.

Most of northern section is hard packed dirt which increases runoff rate.

Planting grass over an area this large would be a big investment and might get in the way of construction if Perry decides to develop the land. But it will reduce flood and legal risks.

Posted by Bob Rehak on 6/20/2020

726 Days after Hurricane Harvey and 275 after Imelda

Contractors Begin Excavation of N1 Detention Pond at Perry Homes’ Woodridge Village

In the last week, contractors have finally started excavating the N1 detention pond at Woodridge Village. Work on the excavation of N2 continues. It also appears that they may have started prep work for excavating the N3 pond. See photos below.

All this comes:

The next Commissioners’ Court Meeting is set for May 19. The agenda for that meeting should be posted May 15.

Excavation Begins on N1 Pond (First Pond on Northern Section)

On May 5, 2020, Jeff Miller, an Elm Grove resident, noticed excavation activity near the Webb Street entrance to Perry Homes’ Woodridge Village. Engineers designated this area for the N1 (first northern) detention pond.

Photo Courtesy of Jeff Miller from Webb Street Entrance in Porter taken on 5/5/2020 shows excavation beginning on N1
Closer photo by Miller from Webb Street Entrance also taken on 5/5/2020
Wider shot by Miller on same date shows additional prep work on N1 site

Miller also shot this video on 5/6/2020, showing the progress contractors have made on the excavation in one day.

Video by Jeff Miller, Elm Grove resident on 5/6/2020.

N2 Excavation Continues

I took the shot below on May 1 with a telephoto lens from the north end of Village Springs in Elm Grove. It shows excavation work continuing on the N2 pond.

Excavation work on N2. Photo taken on 5/1/2020.

Additional Work in Area of N3 Pond

Additional work near area of N3. This excavator was loading up three dump trucks on May 1, 2020.
The dump trucks hauled dirt back to the soupy portion of the Woodridge Villages northern section, then circled back.

On May 5th, Jeff Miller photographed the N3 area from a closer vantage point. It appears only the surface layer has been scraped off so far.

Photo of N3 area courtesy of Jeff Miller taken on 5/5/2020.

Putting New Work in Context of Entire Project

Here’s the layout for the five Woodridge Village Detention Ponds. Contractors finished work on the two southern ponds earlier this year.

Woodridge Village has five detention ponds at various stages of completion. Northern ponds are now under construction. Southern ponds are completed.
At the time of last year’s May flood, only S1 was complete. S2 was substantially completed by September’s flood. The northern ponds had not yet been started.

When the northern detention ponds are complete, the detention system will still not be fully functional because there are no streets or storm drains yet to funnel water into them. Still, some detention is better than no detention with hurricane season three weeks away and an above average season predicted.

City Still Needs to Meet Two Conditions

Perry Homes swears that the work being done now will not affect the purchase price if the County makes a decision on the property by May 15th. At their last meeting, commissioners made the purchase contingent on the City of Houston:

  • Adopting Atlas-14 rainfall statistics
  • Donating $7 million worth of land to HCFCD for flood control projects and to help offset the purchase price of Perry’s property.

No items relating to the purchase appeared on this week’s City Council agenda. But Council meets again next week before the deadline expires.

The County hopes to meet with the City next week to discuss the donation of land. The County also reportedly feels that the four days between Perry Homes’ extended deadline (May 15) and the next commissioners’ court meeting (May 19) will not present a problem if the the City meets the conditions.

Posted by Bob Rehak on 5/6/2020 with thanks to Jeff Miller

981 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.

Perry Homes Pulls Excavation Equipment From Woodridge Village Before Finishing Detention Ponds

Instead of accelerating completion of detention ponds on Woodridge Village as Perry Homes promised, the company appears to have pulled all excavation equipment from the site. Contractors who were supposed to have been working on detention pond N-1 have gone…BEFORE they finished S2 and BEFORE they finished a berm sealing off the southern portion of the site at Fair Grove Drive.

S2 Pond Still Not Complete; Does Not Meet Regs

On October 17th, a lawyer for Perry Homes’ subsidiaries sent a letter to the City of Houston Attorney promising that the company would “accelerate” completion of detention ponds. Even though Perry Homes had already substantially completed Detention Pond S2, it took Perry 63 days to restore it to its pre-Imelda condition. Worse, contractors left before the pond met the regulations in Montgomery County’s Drainage Criteria Manual. It still doesn’t have fencing, service roads around its entire perimeter, or grass on its banks. Finally, it holds water when regulations call for a dry bottom.

Equipment Left Site Instead of Beginning On Next Pond

Perry Homes had promised in its letter to accelerate construction, but this will slow it down – if they ever return. The only work being done Friday? Removal of some dead tree piles on the northern portion of the site.

Jeff Miller took all the pictures and videos below on Friday and Saturday. He also monitored work on the site and provided this scouting report.

Looking south toward Taylor Gully and the Harris County Line along the eastern embankment of the S2 detention pond.
The channel along the eastern portion of Taylor Gully is now lined with concrete. The spillway into the S2 detention pond has been widened and smoothed. The S2 detention pond is behind the camera position. Looking East.
Looking west across S2 detention pond. The dirt that eroded into the pond has been scooped back up onto the banks and compacted. Still no grass on the banks, however, so it could all wash back in with the next big rain.
Looking north. The grassy area in the background was supposed to have contained the N3 detention pond. However, contractors have simply excavated a channel from the northern section directly into Taylor Gully so now runoff can accumulate even more quickly.
Contractors widened and concreted the Taylor Gully channel along the eastern side of Woodridge Village. But they left the most vulnerable part of the channel without concrete. At the end corner by the telephone poles, water comes from the left. But no concrete protects the area where the water makes a sharp 120 degree turn. Expect water to erode behind the concrete and peel it away in the next big rain.

Woodridge Village Section One Now a Virtual “Ghost Town”

This weekend, Woodridge Village Section One looked like a ghost town, not a bustling construction site with people working against a deadline.

Heavy construction equipment used to be parked by dumpster in the background. Now it’s nowhere on the property.
Looking south. Another view of the same area that held construction equipment. It’s all gone and the berm sealing the site off from Fair Grove Drive is missing.

Still Removing Dead Trees/Mulch on Northern Section

On Friday, only smaller equipment turning tree piles into mulch remained.

Perry Homes Intentions Now a Mystery

As of Sunday morning 12/22/2019, no equipment actually working on construction could be seen on the site. The excavators and dump trucks parked at Fair Grove for months have been removed.

Perry Homes is NOT accelerating completion of detention ponds as it promised the City of Houston.

Instead, Perry Homes has thrown a curtain of silence around this job. It’s hard to know what their intentions are. At this point, Perry Homes’ lawyer J. Carey Gray has as much mud on his face as Elm Grove residents had in their homes.

The only thing we can say with certainty: Lowering flood risk for the people of Elm Grove does not seem high on Perry Homes’ priority list.

For Sale And For Lease Signs Serve as Christmas Yard Decorations

Meanwhile, a drive down Shady Maple or Village Springs, the two streets that border Taylor Gully, revealed residents’ attempts to salvage Christmas from the chaos of floodwaters. Dumpsters and debris still line the streets. Some people still live in trailers in their driveways. No apple cider around the hearth for them. They’ll be lucky to find space for a table top Christmas tree. For Sale and For Lease signs outnumber Christmas yard decorations ten to one.

On a street called Right Way in North Kingwood Forest, I found nine For Lease signs in a row. Sad reminders of Imelda and Perry Homes. Only three months ago, these homes were filled with families who flooded for the second time.

Kathy Perry Britton just added another credit to her resume, “The CEO Who Stole Christmas.”

Posted by Bob Rehak on 12/22/2019 with reporting and images by Jeff Miller

845 Days since Hurricane Harvey and 94 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” 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.