Tag Archive for: Woodridge Village Detention

Woodridge Village Excavation Rate Increased Slightly in October

During the month of October 2023, Sprint Sand & Clay excavated another 5,754 cubic yards (CY) of dirt from a new stormwater detention basin on Harris County Flood Control District’s (HCFCD) Woodridge Village property. Compare that to 5,698 cubic yards in September. The new “total to date” is now 156,478 cubic yards. October’s 5,754 CY exceeds Sprint’s monthly minimum of 5,000 CY.

Perry Homes cleared and graded the property for development beginning in 2017. But insufficient stormwater detention capacity contributed to the flooding of Elm Grove and North Kingwood Forest Villages twice in 2019. HCFCD bought the property from Perry in 2021.

Terms of Excavation and Removal Contract

Sprint began excavation in January of 2022 under an Excavation and Removal Contract (E&R). Their 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.

E&R contracts often fluctuate depending on home- and road-building activity nearby. They represent good value for taxpayers because they reduce costs. But they also involve some uncertainty in terms of completion dates.

Where Things Stand at End of October

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 11/1/2336895.6%63.4%
Atlas 14 Requires385100%66%
If Sprint Excavates All 500K Cubic Yards…580150%100%
As of 11/1/23

Rain always slows construction activity and it may have played a role during October.

Pictures of Progress

Here are some before/after pictures (in pairs). They show the progress of construction during October.

Excavation and Removal Progress at Woodridge Village
End of September 2023
End of October 2023

It appears that most of the excavation occurred at the far end. These three shots show the progress made in that area.

Excavation and Removal Progress at Woodridge Village
End of September 2023

End of October 2023, looking NE

End of October 2023 looking SE

Looking back toward the entrance off Woodland Hills…

Excavation and Removal Progress at Woodridge Village
End of September 2023
End of October 2023

How Much Will Be Enough?

HCFCD still has not released the final engineering report for this project. So, we do not know exactly what shape this detention basin will take or what the final volume will be. Regardless, it’s more protection than we had before. And when finished, it will reduce flood risk considerably.

The current rate of excavation when measured in acre feet is about 3.6 per month. That means Sprint would reach the volume required to meet Atlas 14 requirements in about 5 months – the end of the first quarter in 2024. It’s unclear at this time how much HCFCD will have Sprint go beyond that.

NOAA is already working on Atlas 15. Atlas 15 will incorporate the effects of climate change in the national precipitation frequency standards for the first time. NOAA expects estimates to increase. So the size of this detention basin could, too.

Atlas 15 will be the first national precipitation frequency
analysis accounting for climate change

NOAA expects to release the new data for peer review in 2025 and the final study in 2026. After that, NOAA will update the precipitation frequency estimates no less than once every ten years.

There is no such thing as certainty when predicting the future. The good news? There’s plenty of room on this site to expand stormwater detention volume in the future.

Posted by Bob Rehak on 11/1/2023

2255 Days since Hurricane Harvey and 1505 since TS Imelda

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 Rate Ticks Up

The excavation rate of a sixth detention pond on Harris County Flood Control District’s (HCFCD) Woodridge Village property increased during the last month of 2022. That brought the total for the year to 73,745 cubic yards of soil removed under Sprint Sand and Gravel’s Excavation and Removal (E&R) Contract.

The reported total at the end of November was 67,529 cubic yards. That means the total for December was 6,216 cubic yards, the most for any month since last July. Compare the previous totals below.

Woodridge Village E&R totals
Weekly totals through November

Excavation under E&R contracts varies depending on demand for fill dirt. Sprint’s contract with Harris County Flood Control District lets it take dirt basically for free and then sell the dirt on the open market to make its money.

The work could more than double the stormwater detention capacity on the site that flooded Elm Grove and North Kingwood Forest twice in 2019.

According to HCFCD, E&R agreements provide an opportunity for making progress in advance of future basin construction. These agreements essentially provide a head start in the excavation process before the detention basin is designed and constructed. In these agreements, an excavation company agrees to remove soil from a basin site during an agreed upon time period for minimal compensation. This is a cost-effective way for the material to be removed and it also provides significant savings by minimizing trucking and disposal fees. 

Pictures Taken 1/03/23

Looking west toward the site entrance on Woodland Hills Drive.
Contractors appear to be leaving some existing concrete culverts in place that will allow the new pond to drain into the old one at the top of frame.
Looking NE. The pond could eventually extend as far as the grove of trees in the distance.

Part of a Bigger Package of Improvements

Last month, HCFCD held a virtual public meeting to describe how this would eventually contribute to flood-risk reduction on Taylor Gully.

HCFCD expects that Sprint will excavate the full 500,000 cubic yards stipulated in their contract. That will expand the current stormwater detention capacity by 166%. The property only needed 40% more to meet Atlas-14 requirements. So this will provide a considerable margin of safety.

Other improvements include:

  • A concrete-lined, low-flow channel within the existing channel to expand conveyance from 350 feet downstream of Creek Manor Drive to 1500 feet downstream of Mills Branch Drive. The concrete portion would be four feet deep and 20 feet wide.
  • A new clear-span bridge at Rustling Elms to replace the current bridge over two culverts.
Taylor Gully/Woodridge Village
Scope of preliminary engineering project

For more details and diagrams, see this post on the preliminary engineering recommendations.

Posted by Bob Rehak on 1/5/23

1955 Days since Hurricane Harvey and 1204 since Imelda

New Woodridge Village Detention Basin About 12% Excavated, Engineering Study Almost Done

A new Woodridge Village Stormwater Detention Basin that could almost double detention capacity on the site continues to move forward slowly as housing starts slow. The trend at Woodridge seems consistent with other excavation and removal (E&R) contracts countywide.

Meanwhile, the first draft of a preliminary engineering study for the Woodridge site and Taylor Gully is complete and going through management review at Harris County Flood Control District (HCFCD).

Status of E&R Contract on Woodridge Village Site

As of mid-September 2022, Sprint Sand and Clay had removed 57,785 cubic yards of dirt from a planned detention basin on the Woodridge Village property in Montgomery County. Sprint is working under an E&R contract with HCFCD. The contract calls for them to remove up to 500,000 cubic yards at a minimum of 60,000 cubic yards per year or 5,000 per month.

Looking NE across new basin. Last month, it extended as far as the middle of the far pile of concrete pipes on the right.

So the company, which began work in February, has virtually met its first year minimum after eight months. However, the rate has slowed somewhat in recent weeks as housing starts have slowed due to a rise in interest rates. In the last four weeks for which totals are available (8/22/22 – 9/18/22), Sprint has removed only 3,045 cubic yards. To date, that brings the total excavated to 12% of the contract max.

Housing starts in the South have been especially hard hit. According to the Census Bureau, starts in August fell 13.5% compared to July and 15.4% compared to a year ago. That depresses demand for fill dirt and makes it harder for Sprint to find buyers for it.

Under the terms of its HCFCD E&R contract, Sprint gets only $1,000 for removing up to 500,000 cubic yards, but has the right to resell all the dirt at market rates. That’s how it makes its profit.

Woodridge Vs. Countywide Data

To see whether Woodridge was an anomaly or part of a trend countywide, I asked HCFCD to show readers the bigger picture. Alan Black, Deputy Director of Engineering and Construction supplied the data below. The chart shows the trend in all HCFCD E&R contracts countywide going back 10 years.

Source: HCFCD via FOIA Request

All data is open to interpretation. But I see three main “regions” in the chart above.

  • The first is pre-flood bond – before August 2018. With the exception of a few blips, excavation remained below 5,000 cubic yards per month. That’s roughly equal to the average being removed from Woodridge Village each month.
  • The second is a huge spike that occurred after flood-bond approval. it peaked at almost 35,000 cubic yards per month as HCFCD readied engineering studies on more than 180 projects countywide.
  • Third, HCFCD had a sharp falloff at the start of the pandemic in January 2020. After things stabilized, we see a gradual rebuilding. It coincides with a housing boom and is followed by another gradual drop-off. The latter coincides with rising interest rates and falling housing starts.

Regardless, the trend in the last few months does not bode well for those concerned about finishing the new Woodridge Stormwater Detention Basin quickly.

Looking W. The new Woodridge Village stormwater detention basin at the top of the frame could eventually fill most of the area between the road on the left and the ditch on the right.

Status of Preliminary Engineering Study on Taylor Gully

We should remember, however, that HCFCD always intended the Woodridge E&R contract as a head start on excavation while IDCUS finished its preliminary engineering study on Taylor Gully and Woodridge Village. The study began in mid-2021. IDCUS had 300 days to complete it.

IDCUS submitted the first draft of its results several months ago.

Amy Stone, HCFCD spokesperson

Since then, HCFCD staff has reviewed it and asked IDCUS to take a closer look at some areas, said Stone. At this point, the revised draft is working its way up to HCFCD top management for final review and comment. HCFCD has started preparing a presentation for all those affected in the area and exploring the best dates for a community input session.

Assuming HCFCD management doesn’t ask IDCUS for more revisions, we should know recommendations and next steps this fall. Following a public comment period, more changes may need to be made to engineering plans before design and construction start.

Folks who flooded in Elm Grove and North Kingwood Forest as well as others farther downstream in Mills Branch and Woodstream Village eagerly await the findings. More news when it becomes available.

Posted by Bob Rehak on 9/30/2022

1859 Days since Hurricane Harvey

Update on new Woodridge Village Detention Pond

At the end of August, I checked with Harris County Flood Control District (HCFCD) to see how excavation of the new Woodridge Village detention pond was coming and what the next steps are.

Before and After Photos

The two photos below show the extent of excavation at the end of July and today.

Woodridge Village Excavation
The far end of the pond reached slightly past the second cluster of storm sewers at the end of July.
By the end of August, excavation had reached the far end of the second pile of storm sewers.

Eventually, the new detention basin could reach to or past the cluster of trees in the background.

Rough layout for new Woodridge basin.
Rough layout showing the excavation limits for Sprint. Right now, they’re in the lower left of the green area.

Progress by the Numbers

From February through August, 2022, Sprint Sand and Clay has removed 55,167 Cubic Yards of dirt from the area where a new detention pond will eventually be built.

Eventually, they could double the amount of detention on the site. Sprint’s contract lets them remove up to 500,000 cubic yards and sell the dirt at market rates. In exchange, HCFCD will pay them only $1,000. The minimum amount to be removed under the contract is 5,000 cubic yards per month.

Since January, Sprint has managed to beat the minimum each month. But regular reports show the rate of excavation slowing with the housing market.

Sprint began work on January 27, 2022.

By mid-April, Sprint was averaging a little more than 14,000 cubic yards per month.

But by the end of July, the average fell to 8,000 cubic yards per month.

And in August, Sprint removed only 6,307 cubic yards.

At 6,000 cubic yards per month, Sprint exceeds the contract minimum. But it would take the company another six years to reach 500,000 cubic yards. Flood-weary Elm Grove and North Kingwood Forest residents pray it doesn’t take that long.

Slowing Rates Reflect Slowdown in Housing

The slowing rates of removal reflect a slowdown in the housing market. The Census Bureau reports that privately‐owned housing starts in July were 9.6 percent below June and 8.1 percent below July 2021. TradingEconomics.com reports that the housing sector has been cooling down amid soaring prices of materials and rising mortgage rates. The Census Bureau has not yet released August rates.

Luckily, this project and others in the Kingwood Area could potentially accelerate soon.

Status of Preliminary Engineering Review on Taylor Gully

Idcus should be done with the Taylor Gully preliminary engineering review this fall. However, the Idcus contract does not include design of the detention basin that Sprint is working on. According to Alan Black, HCFCD Director of Operations, that design will need to go under a separate contract.

Funding for Design and Construction

That’s because US Congressman Dan Crenshaw secured a $1.6 million earmark earlier this year that will pay for design. Crenshaw has also requested another $10 million earmark to complete the actual construction of the Woodridge Basin when design is finalized.

According to Black, HCFCD can’t just extend the Idcus contract. HCFCD will have to start over with a request for qualifications (RFQ) for final design of the Woodridge Village detention basin and other improvements along Taylor Gully.

“That’s because the money that we’re going to use is coming from this year’s earmark from Congressman Crenshaw,” said Black. “Because federal funds are involved, we have to issue a new RFQ. We can’t use the consultant we already have just by default. So it will take us a little bit longer. By the end of this year or the beginning of next, we need to get a consultant selected, based on qualifications, once those grants come to fruition. In this case, they will be through the EPA.”

Other Crenshaw Requests to Help Lake Houston Area

As reported last night, in the immediate future, funding for projects in the Lake Houston Area will likely have to come from the Federal, State or City governments. Crenshaw has requested $10 million for construction of the Woodridge Basin, $8 million for the Lake Houston Dam Spillway Improvement Project, and another $10 million to construct another detention basin along Cedar Bayou. Crenshaw already secured another $1.6 million for final engineering of improvements to the Kingwood Diversion Ditch.

Posted by Bob Rehak on 9/2/22

1830 Days since Hurricane Harvey

July Update: Woodridge Village Excavation Rate Slows Slightly

The pace of excavation and removal of up to 500,000 cubic yards of soil from Woodridge Village has slowed slightly in recent months. That may be due to rising interest rates, which have slowed housing starts. Contractors use excavated dirt to elevate homesites in new developments. But the Census Bureau says housing starts in June 2022 fell 6.3% below the June 2021 rate.

Woodridge Village Background

Woodridge Village was the failed 670-acre Perry Homes development that twice contributed to flooding hundreds of homes in Kingwood’s Elm Grove and North Kingwood Forest Villages in 2019. Harris County and the City of Houston bought the property in 2021 to help reduce flood risk. They plan to do this by building another detention basin.

Perry left the site about 40% short of the floodwater detention capacity needed to meet current Atlas-14 requirements. Since then, Harris County Flood Control District (HCFCD) entered into an “Excavation and Removal” contract (E&R) with Sprint Sand and Clay to begin removing additional soil. The goal: to get a head start on building an additional detention basin that would meet OR exceed Atlas-14 requirements.

Harris County Commissioners Court approved the contract with Sprint Sand and Clay on July 20, 2021. It obligates Sprint to remove at least 5000 cubic yards per month. Excavation started on January 27, 2022. 

During July, Sprint removed approximately 6,400 cubic yards of dirt.

HCFCD spokesperson Amy Stone

To date, Sprint has removed 48,860 yards of material. That’s 18,860 cubic yards more than the contract minimum for six months. And 1,400 cubic yards more than the minimum for July. So you can see that the rate of removal is dipping slightly.

At almost 50,000 cubic yards for 6 months (or 100,000 yards per year), it would take 5 years for Sprint to reach the maximum. However, by contract, Sprint has 36 months. If Sprint continues to average 6,000 cubic yards per month for another 30 months, it would remove a total of 229,000 cubic yards before the end of the contract term ([30×6000]+ 49,000). 

So at some point, Sprint will have to sprint to catch up if they want to remove all 500,00 cubic yards.

Recent Photos Show Growth of Basin

Here’s what the site looked like before and after July’s excavation activity.

End of June
Woodridge Village E&R as of 6/30/22
Excavation at end of June 2022. Note where the upper right boundary of the pit stops relative to the storm-sewer pipes at far right.

End of July

End of July 2022.
Looking south over eastern edge of pond. Newly excavated area is at left (darker dirt).

About E&R Contracts

E&R contracts provide a head start on construction of detention basins before completion of their final design. 

Sprint has agreed to remove up to half a million cubic yards of soil for only $1000. But it makes its money back by selling the soil for a profit on the open market. This provides virtually free excavation to taxpayers and virtually free raw material to Sprint. HCFCD has spent only $230 on the project so far. But the tradeoffs are speed and certainty.

The property above forms the headwaters of Taylor Gully. When HCFCD finishes its Taylor Gully study, things may change.

Final Needs Contingent on Outcome of Taylor Gully Study

HCFCD hired Idcus, Inc. in mid-2021 to develop up to five conceptual alternatives for modifying Taylor Gully. Scenarios may include:

  • Expanding Detention On Woodridge Village so that no channel improvements are necessary.
  • Determining amount of detention and channel improvements necessary to ensure no adverse impact all the way to Lake Houston.
  • Finding the optimum balance between maximum flood protection and minimum construction costs.
Deliverables include:
  • Channel and basin layouts
  • Estimates of benefits for various levels of storms (100-year, etc.)
  • Right-of-way requirements
  • Cost estimates for right-of-way acquisition, engineering and construction management.
  • Performance metrics, i.e., estimated acreage of land inundation, number of structures in floodplain, number of structures flooded and miles of inundated roadway.
  • A scoring matrix to rank alternatives.
The red dots show location of current excavation relative to entire scope of Idcus project, from yellow polygon on left to end of red line in forest on right.

Idcus should be done with the study soon. In the meantime, residents will have to settle for the virtually free head start we get.

Posted by Bob Rehak on 7/31/2022

1797 Days since Hurricane Harvey

1182 Days since May 7, 2019

1049 Days since TS Imelda

New Woodridge Village Detention Pond Taking Shape

Sprint Sand & Clay has begun excavating a new Woodridge Village detention pond on the former site of Perry Homes’ aborted development. Harris County Flood Control District (HCFCD) signed an excavation and removal (E&R) contract with Sprint last November to remove up to 500,000 cubic yards for just $1000. In exchange for the dirt-cheap fee, Sprint gets to sell the material it removes at market rates to make its profit.

Photos of Progress

Taxpayers like such contracts. But they have one potential drawback. If the market softens, it could take years to remove all the material. Progress to date has been slow, but steady.

Extent of removal on 2/14/22.
Three days later, on 2/17/22.
One day later on 2/18/22.

Harris County Flood Control executives emphasized that E&R contracts provide flexibility to both sides. They let Sprint move the material when it’s needed. And they let the Flood Control District get a head start on construction of detention ponds that they know they will need.

Perry left the Woodridge Village site 40% short of Atlas-14 requirements for detention-pond capacity. Five-hundred-thousand cubic yards will virtually double the detention-pond capacity, leaving a significant margin to help accommodate future upstream development.

An engineering study on Taylor Gully is currently underway. When completed, we will learn more about future needs. But that could still be months away.

HCFCD currently has no plans to tie this detention pond into the network of five others on the Woodridge site. It will just form a barrier against sheet flow from the north for the moment. Tie-ins with the existing drainage network could come after completion of the Taylor Gully engineering study.

After completion of the study, when HCFCD has a better handle on how much land it actually needs on the site, the District will hold public meetings to discuss secondary uses of the land, such as wetland restoration, reforestation, jogging trails, parkland and such.

HCFCD met with members of KSA and community associations that border Woodridge property last week to discuss the timetable. The ability to create secondary uses for the land will depend on finding local partners to maintain them. Flood control would only be responsible for maintaining its own flood control infrastructure (ponds, ditches, etc.).

Where Dirt Can, Can’t Go

Sprint has broad latitude with where it can sell the dirt from Woodridge Village. But HCFCD does impose limitations. It cannot be placed in the current 100- or 500-year flood plains.

According to Alan Black, Interim Executive Director of HCFCD, “We place some pretty stringent criteria in our E&R contract agreements requiring that fill from our project sites can only be placed in areas where a permit has been obtained. But we actually go a step further.

“It is possible for developers to obtain a permit that includes fill in the 100/500 year floodplain provided that it is property mitigated,” continued Black. “However, HCFCD contractors are prohibited from placing fill in the 100/500 year floodplain even if there is a development permit to do so. This has resulted in an increase in our construction costs, but it’s the right thing to do.”

Black is referring to the City of Houston rules for placing fill in floodplains. See sec 19-34 of the City code of ordinances. Remember that the “Houston special flood hazard area” means the 500-yr. Section 19-34(a) says nobody can diminish the storage volume within a Houston special flood hazard area. However, this is followed by an exception. Paragragh A4 says fill may be placed… “In the 0.2 percent chance floodplain, [if] the amount of fill proposed does not impact or impede the 100 year overland sheet flow in the watershed.”

Regardless of the City regulations, HCFCD refuses to let its dirt be used in this situation.

Posted by Bob Rehak on 2/21/22 

1637 Days since Hurricane Harvey