Tag Archive for: Cutten Basin

Greens Bayou Detention Basin Capacity Steadily Growing

Harris County Flood Control District (HCFCD) and its partners continue to add detention basin capacity along Greens Bayou to reduce the risk of flooding. I flew in a helicopter today with fellow Harris County Community Flood Resilience Task Force members Ken Willians and Bill Calligari. We flew over Greens, Halls, Hunting, and White Oak Bayous. In this post, let’s focus on what we found in Greens.

From west to east, we flew over the Cutten Basin at 249 and Beltway 8, then followed the bayou over the Antoine, Kuykendahl, Glen Forest, Aldine-Westfield, and Lauder Basins. Some have recently completed construction. Others are still under construction. Here’s a rundown of everything between US249 and US59 along Greens.

Cutten Basin

Scheduled for completion later this year, the Cutten Basin covers approximately 250 acres. It includes five compartments, four south of Greens Bayou and one north. When complete, it will hold 850 acre feet of stormwater. That’s enough to hold a foot of rain falling across approximately 1.3 square miles. It will lower the water surface elevation along Greens by a third of a foot in a hundred-year flood.

Looking S toward Beltway 8. Greens Bayou flows from right to left through the center of the frame.
Looking East. Greens cuts through the upper left portion of the frame. Beltway 8 cuts through the upper right.
Looking West across Hollister which cuts through the middle of the frame.

Antoine Basin

HCFCD and the Army Corps started the $80 million Antoine Basin in 2015. The Army Corps designed and built it. Satellite photos in Google Earth first show it holding water in November 2020.

Looking east along Greens toward the Antoine Basin, top right.
Looking SW. West Greens Road arcs through center of frame. Greens flows from upper right to lower left. Beltway 8 near top of frame.

The completed basin holds approximately 1,650 acre-feet, or 538 million gallons of stormwater. To put that in perspective, it holds a foot of rain falling over a 2.5 square mile area, or half a foot falling across 5 square miles!

Kuykendahl Basin

Kuykendahl Stormwater Detention Basin sits on a 288-acre property near Kuykendahl Road and Ella Boulevard along an unnamed tributary of Greens Bayou. In floods, it holds water back from entering the bayou and then releases it safely and slowly after the storm has passed.

Wide shot of Kuykendahl Basin looking west
Kuykendahl in foreground. Note how densely populated the area is with apartments.

Contractors removed 3.61 million cubic yards of soil from the site. It holds 2,325 acre-feet, or 757.6 million gallons of stormwater. That’s a foot of rain falling across 3.6 square miles, or half a foot falling across 7.2.

Following construction, contractors planted 22.19 acres of native tree and shrubs, and 12.79 acres of stormwater quality-treatment wetlands. They also created 14.04 acres of other wetlands to replace those impacted by construction.

Ceres Environmental Services Inc. constructed the Kuykendahl basin and another to the east (see Glen Forest below). Combined, they were the largest construction contract ever managed by HCFCD up to that time. The two basins reduced or removed flooding risks and damages from more than 1,100 structures along Greens Bayou. “Avoided damages” exceed $90 million in every flood. Far more than the cost of construction.

FEMA awarded $39.2 million to the Harris County Flood Control District, under the Hurricane Ike Hazard Mitigation Grant Program (HMGP) to construct the basins and HCFCD contributed matching funds.

Google Earth satellite photos indicate construction finished for both basins in 2020.

Glen Forest

Farther east along Greens, the Glen Forest Detention Basin extends from I-45 to Imperial Valley north of Greens Road.

Looking East across I-45 at Glen Forest Basin.
Looking West at Glen Forest Basin on Greens Bayou between I-45 at top of frame and Imperial Valley Drive under camera position.

The Glen Forest Basin project removed approximately 2.15 million cubic yards of soil in three connected cells. The completed basin holds approximately 894 acre-feet. That’s 1.4 square miles one foot deep or 2.8 square miles a half foot deep.

Aldine Westfield Basins: Phases 1 and 2

Farther east along Greens Bayou, directly south of Houston’s Bush Intercontinental Airport, you will find two more new basins. HCFCD completed construction on the first in April 2021. The second (to the north) then began construction and has not yet finished.

Looking East from over Aldine Westfield Road in foreground at Phase One. Beltway 8 in upper right. Note Greens Bayou turning south under Beltway in upper right.
Looking ENE. Phase 2 is still under construction on Aldine-Westfield Road immediately north of Phase 1 (lower right). Note airport tower on horizon.

Phase 1 holds approximately 667 acre-feet of stormwater and Phase II will hold another 600 acre-feet. Two 5’x4′ reinforced concrete boxes will connect the two phases and outfalls into Greens Bayou.

Together the two basins will hold a foot of rain falling over more than two square miles.

Lauder Basin

1.5 miles to south of the Aldine-Westfield Basins, you will find the Lauder Basin: Phases 1 and 2.

Looking S at Phase I of the recently completed Lauder Basin. Greens Bayou is on right, flowing top to bottom.

Phase 2 of the Lauder Basin is starting in the forested area in the upper right of the photo above.

Phase 1 completed construction late last year. In May of 2022, the Texas Water Development Board granted HCFCD more than $2.2 million to begin Phase 2.

The two basins when complete in 2024 will hold a foot of rain falling over more than 2 square miles (1260 acre feet). That concludes your helicopter flight down Greens Bayou for today.

Greens by the Numbers

Together, these basins should hold approximately a foot of rain falling over 12 square miles.

That’s not enough to prevent flooding in another Harvey. But it will certainly reduce flooding for thousands of people. HCFCD has not yet released updated flood-risk data for the mid- and upper reaches of Greens Bayou (shown above). More news on that when it becomes available.

According to data obtained from HCFCD via a FOIA Request, Flood Control and its partners have spent more than $435 million on flood mitigation in Greens Bayou between 1/1/2000 and the end of last year. That includes money spent on all phases of all projects shown above.

Only three other watersheds have received more funding since 2000: Brays, White Oak and Sims. But more on those later.

Greens was the second most heavily damaged watershed in five major storms (Allison, Tax Day, Memorial Day, Harvey, Imelda). Those storms damaged more than 29,000 Greens structures.

58% of the population of Greens has low-to-moderate income (LMI). That ranks 6th on the LMI scale of Harris County watersheds.

Posted Bob Rehak on 7/19/22

1785 Days since Hurricane Harvey

Where Flood-Bond Spending Is Going, When New Flood Maps Will Be Released

On the Harris County Commissioner’s Court agenda for today are two Harris County Flood Control District (HCFCD) “transmittals.” One will update commissioners on flood-bond spending to date. The other will update commissioners on the progress of new flood maps (the MAAPnext program). They are items 269 and 270 on today’s agenda.

Transmittals are reports by departments. Commissioners don’t usually discuss them unless one of the commissioners wishes to make comments for some reason. So, I’m calling them to your attention here.

Flood-Mitigation Spending Through Third Quarter Reaches $865 Million

About half of the $865 million spent on flood mitigation since voters passed the bond in 2018 has come from bond funds. The rest has come from grants and local partnerships. See pie chart below on left.

The left pie chart underscores the importance of partnership funding.

The map below shows where flood-bond spending has occurred.

Flood-mitigation spending by watershed since approval of flood-bond in 2018.

The winner in the $weep$take$: HCFCD spent almost $154 million on Brays Bayou.

Other leading watersheds (rounded to nearest million) in flood-bond spending included:

  • $81 million in Addicks Reservoir
  • $76 million on Greens Bayou
  • $76 million on Cypress Creek
  • $50 million on Little Cypress Creek
  • $46 million on White Oak Bayou
  • $32 million on Clear Creek

With a few exceptions, this spending reflects the influence of the Harris County Flood-Bond Equity Prioritization Framework implemented in 2019. That framework gives highest priority to low- to middle-income watersheds with a high social-vulnerability index. Thus, tiny Halls Bayou has received more assistance than the largest watershed in the county – the San Jacinto River. And Brays Bayou has received almost 11 times more assistance than Buffalo Bayou.

Two notable exceptions are:

  • Vince Bayou which is almost totally inside the City of Pasadena and is therefore primarily Pasadena’s responsibility.
  • Little Cypress Creek which is part of HCFCD’s experimental Frontier Program. The Frontier Program aims to prevent future flooding by buying up land on the cheap before it’s developed. HCFCD then sells detention basin capacity to developers to help make back its investment.

Other Insights Gained from Report

  • Most projects are ahead of schedule and on budget. Good news!
  • More than half of buyouts have been completed and enough funding apparently remains to complete the rest.
  • Progress continues on the $124 million FEDERAL Flood Damage Reduction project on White Oak Bayou, where six stormwater detention basins will hold almost a billion gallons of stormwater. That’s equivalent to about a foot of stormwater falling over almost 5 square miles.
  • No actual projects in the Kingwood Area have begun construction yet. However, the Excavation and Removal Project on Woodridge Village could soon begin.

Additional maps in the full report show:

  • Dollars funded to date by watershed (Note, for instance, another $47 million in funding already committed to Brays).
  • Active Maintenance projects
  • Active Capital projects

Also, a massive GANNT chart shows the stages of every project in every watershed and county-wide projects.

Check out the full report here.

Controversy over Previous Version of Report

An earlier version of this report generated some controversy. People in some watersheds didn’t believe the reported expenditures. Members of the Northeast Action Collective questioned whether any projects had started in their watersheds. They demanded immediate cancellation of projects in Kingwood and transfer of Kingwood’s funds, so that projects in Halls and Greens Bayou could start immediately.

That’s, in part, why I wrote “How to Find and Verify Flood-Related Information: Part I.” Flood-mitigation projects are hard to spot from the ground. Construction almost always happens out of sight behind tall fences and dense tree lines. After construction, the projects are often disguised as parks. For those who doubt, I recommend confirming the existence of projects from the air.

I haven’t confirmed every project in the county, but I have spot-checked many. And I have yet to find discrepancies between what HCFCD reports and what I can see from the air.

C-25, a Halls Bayou Detention pond now under construction by HCFCD
C-25, a Halls Bayou Detention pond now under construction by HCFCD. The bayou runs through the trees in the foreground.
flood detention basin
New basin at Hopper and US59 on a tributary of Halls Bayou.
Lauder Detention Basin on Greens Bayou as of 10/12/2021
Lauder Detention Basin on Greens Bayou as of 10/12/2021. Phase One of a two-phase project is nearly complete.
Cutten Road detention basin on Greens Bayou continues its relentless expansion.
Phase 2 Aldine Westfield Basin
Phase 1 of the Greens Bayou Aldine-Westfield Basin on left is complete. Phase 2 on right is now beginning.

For more information that includes watershed spending data before the flood-bond, check out the funding page.

MAAPnext Effort About to Be Turned Over to FEMA

Harris County Flood Control (HCFCD) estimates it has completed 86% of its part of the flood-map updates. HCFCD will deliver drafts of the new maps to FEMA in January for review and kick off a campaign of public meetings at the same time. The public will see draft maps in February. A public comment period of 90 days will follow. And FEMA hopes to release preliminary flood insurance insurance rate maps by mid-year next year.

I have had a peek at the new maps and reports. And I must say, the effort should result in a dramatic leap forward in flood-risk understanding. Individualized reports will inform homeowners of their flood risks from a variety of different sources, including street flooding. The prototype of the website is very user friendly.

After receiving preliminary maps from HCFCD, it typically takes FEMA another 18-24 months to release final, official flood maps. That gives affected property owners time to comment and appeal. The process looks like this.

MAAPnext milestones as of the end of 2021.

Posted by Bob Rehak on 11/30/2021

1554 Days since Hurricane Harvey

HCFCD Continues Relentless Expansion of Cutten Basin on Greens Bayou

Where Greens Bayou cuts across the northwest corner of Beltway 8 and 249, Harris County Flood Control District is expanding its Cutten Regional Stormwater Detention Basin.

Location of HCFCD’s Cutten Floodwater Detention Basin
The basin includes 5 separate Basin Compartments (BCs). One is on the north side of the Bayou (BC5) and four are on the south side (BC1-4).

The $16.2 million expansion will add 866 acre-feet of stormwater storage capacity to the previous 677 acre-feet. That’s enough to lower the water surface elevation by .36 feet throughout the surrounding floodplain.

When complete, the 235-acre complex will have enough capacity to hold a foot of stormwater falling over 2.4 square miles.

Photos Taken 10/15/2021 Show Current Construction Status

Looking E at the extension of Greens Road between BC3 (right) and BC4 (left). Red line indicates path of culvert under roadbed.
Looking W in opposite direction. Greens Bayou is on right. Greens Road (coming from top of frame) will be extended south along ridge that bisects BC3 and BC4 in foreground. BC1 and BC2 are in background on either side of Greens Road. Hollister cuts through the frame from left to right.
Looking NW across Hollister toward yet another detention pond, BC5.
Looking SW across the intersection of Hollister (left) and Greens Road (right). Excavation of BC1 still has a way to go. On Friday, muddy conditions were slowing down the work, but if you look closely, you can still see heavy equipment working in the distance.

How Ponds Will Work with Bayou, Surrounding Developments

These ponds will function two ways. They will take stormwater:

  • Out of Greens Bayou when it starts to overflow.
  • Directly from surrounding subdivisions before it gets into the bayou.

This presentation describes more about the Cutten Basin.

It’s important to understand that County/Municipal neighborhood drainage and HCFCD infrastructure often pre-date current building and development codes, as they do in this area.

As cities and precincts re-grade and reconstruct streets with more and bigger storm sewers that get water out of neighborhoods faster, that water needs a place to go – without flooding others downstream.

In this area, these ponds will be that place. Everything has to work together. The very first sentence of the Texas Water Code Section 11.086 states, “No person may divert … surface waters in this state … in a manner that damages the property of another…”

Stormwater detention basins like these also provide greenspace and recreational opportunities, such as public parks.

HCFCD expects to complete the Cutten Project in the summer of 2022.

Cutten Basin Size in Perspective

To put the size of this basin in perspective, it roughly equals the size of Woodridge Village. Woodridge is the aborted Perry Homes development in Montgomery County. HCFCD purchased it earlier this year to build a regional Stormwater Detention Basin on Taylor Gully in the Porter/Kingwood area.

The Woodridge site already contains five small detention ponds and HCFCD has room in the center to add more. Perhaps the Woodridge site will look somewhat like this one before things are all over.

Cutten is one of six detention basins (Cutten, Antoine, Kuykendahl, Glen Forest, Aldine-Westfield, Lauder) either recently constructed or almost constructed by the Army Corps and HCFCD in the mid and upper reaches of Greens Bayou. HCFCD is also studying a number of flood mitigation projects on the lower reaches of Greens.

Posted by Bob Rehak on 10/16/2021

1509 Days after Hurricane Harvey and 758 since Imelda

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

Construction of HCFCD Greens Bayou Flood Mitigation Projects in High Gear

One of the largest watersheds in northern Harris County is Greens Bayou. It drains 212 square miles with a population of more than half a million people. It encompasses portions of the cities of Houston and Humble.

Greens Bayou and its tributaries have flooded homes and businesses numerous times in the last two decades. Tropical Storm Allison in 2001 and Hurricane Harvey in 2017 produced devastating floods thanks to large floodplains and high-density development.

An Equity Priority

As a result of high percentages of low-to-moderate income neighborhoods as you work your way east and south along the bayou, flooding in Greens received a high priority in the Harris County’s Equity Prioritization Framework.

Harris County Flood Control District currently has three projects in construction along Greens Bayou with more on the way. One of the three is virtually complete. When I photographed it today, I found contractors doing a final inspection. Here’s a rundown of current and future projects.

Greens Bayou runs roughly parallel with the North Belt before turning south and eventually joining Buffalo Bayou. Projects 1 and 3 are large scale detention projects under construction. Phase 1 of Project 2 is virtually complete.

Project #1: Cutten Stormwater Detention Basin

HCFCD is currently excavating a massive 235-acre stormwater detention basin near Cutten Road and State Highway 249. It will reduce flooding risks in the Greens Bayou watershed by taking in excess stormwater during heavy rain events and then releasing it slowly back to the bayou when the threat of flooding has passed.

Map of the Cutten Detention site courtesy of HCFCD.

The project is budgeted at $16.2 million. And it is approximately one-quarter complete. I took the pictures below on 4/20/21.

Looking SW at the Cutten Basin with the Beltway 8/SH249 intersection in the background. Greens Bayou flows diagonally from the upper right to lower left.
Tunnels under Greens Road will let water flow from the northern section to southern
Looking NE across Hollister Road toward another section of the basin that will connect to the rest via tunnels.
A relentless carousel of trucks carries away one layer of the basin after another.

Project #2: Aldine Westfield Stormwater Detention Basin

Further down the bayou, the Aldine Westfield Stormwater Detention Basin is located just north of Beltway 8 and east of Aldine Westfield Road. The first phase of this project is virtually complete. It sits in a no-fly zone for drones because of its proximity to Bush Intercontinental Airport. So you will have to make do with a ground-level construction photo stitched together in Photoshop from five separate exposures.

Looking SE at Phase One of the Aldine Westfield Basin. Contractors have just finished planting trees to stabilize the slopes. Phase Two has yet to start. It will be to north (left) of this basin.
Phase One has just completed. Phase Two is in permitting.

South and north segments are being constructed in two phases because of environmental permitting. Eventually, the two basin compartments will connect via a 48-inch pipe and will outfall into Greens Bayou.

The first phase above cost $7.7 million. The second will cost $11.3 million.

HCFCD

Because of the location just south of Bush Intercontinental Airport, this basin will not have a permanent pool. Reason: to avoid attracting waterfowl which could create a hazard to aviation.

The two basins will eventually hold approximately 1,250 acre-feet, or more than 407.3 million gallons, of stormwater that otherwise might flood homes and businesses during heavy rain events. The benefits of this project are best understood as part of a suite of projects – Progress Greens – that will work together to reduce flooding risks within the 213 square miles of the Greens Bayou watershed.

Part of Project Greens

Project Greens is a suite of flood damage reduction projects. The Harris County Flood Control District is taking the lead in some, with grant assistance from the Federal Emergency Management Agency (FEMA). In others, the U.S. Army Corps of Engineers will design and construct the project, with partnership assistance from the Flood Control District. 

All projects under the Progress Greens umbrella will function together to reduce flooding risks and damages for residents and businesses within the 213 square miles of the Greens Bayou watershed.

The Aldine Westfield Stormwater Detention Basin project is and will be funded both through the Flood Control District’s Capital Improvements Program and the 2018 Bond Program. If partnership funds are not available, the project will be funded totally from the 2018 Bond Program as a “Local Only” project.

Project #3: Lauder Stormwater Detention Basin

The Lauder Stormwater Detention basin is another 2-phase project. Phase One, just north of Lauder Road and west of JFK Boulevard, will cost $18 million when complete. Phase Two will cost another $20.5 million and be located west of Phase One in parts of the Castlewood subdivision which HCFCD has bought out. Harris County Commissioners Court accepted the Preliminary Engineering Report and authorized the design and construction of Phase Two of the stormwater detention basin.

The photos below show the status of Phase One.

When complete, the Lauder Stormwater Detention Basin will hold at least 1,200 acre-feet, or more than 391 million gallons of excess stormwater. According to HCFCD, the project will reduce risk in more common 10 percent (10-year) floods, but would be overwhelmed in a much larger storm.

While driving around this area, I noticed a new home ten-feet up on stilts, while older homes sat at ground level. Commercial and industrial development around Bush Intercontinental Airport has literally swamped this area. This Lauder Basin is also part of Progress Greens.

The photos below show the status of Phase One construction on 4/20/21.

Looking north from the construction entrance at Lauder Road.
Looking East at the Lauder Basin construction staging area.

The Lauder Stormwater Detention Basin project is being funded both through the Flood Control District’s Capital Improvements Program (for design) and through the 2018 Bond Program (for construction).

Total Cost for Greens Bayou Projects in Construction

Altogether, construction of these three projects will cost approximately $42 million. Phase Two of Aldine Westfield and Lauder basins will cost another $31.8 for a total of almost $74 million. Phase 2 of the Aldine Westfield construction will kick off this summer. And Phase 2 of the Lauder project will start next winter.

Posted by Bob Rehak on 4/29/2021

1330 Days since Hurricane Harvey