News - Reduce Flooding

Aldine-Westfield Detention Basin Phase 2 Construction Starting Along Greens Bayou

In April this year, I posted about Harris County Flood Control District’s (HCFCD) completion of the Aldine-Westfield Detention Basin Phase 1 along Greens Bayou. Now construction of Phase 2 is starting. It’s currently in the clearing phase.

The basin sits east of Aldine-Westfield Road at Beltway 8 North just south of Bush Intercontinental Airport.

Aldine Westfield Basin layout — *Aldine-Westfield Basin location*

Photos from April and October

Here’s how that looks from the air.

Looking NE from over Beltway 8 and Aldine-Westfield Road in a helicopter in May. Phase 1 in foreground had just been completed. Red rectangle indicates approximate location of Phase 2 which had not yet started. Note airport in background *and Greens Bayou in foreground.*

I didn’t have a helicopter this morning and I wasn’t able to safely launch a drone because of air traffic. However, I did manage to grab some ground-level shots from the entrance to the Phase 2 construction site on Aldine-Westfield road.

*Photo taken on 10/15/2021 from Aldine-Westfield Road shows that clearing of Phase 2 has begun.* *The site is currently in the clearing phase.*

The photo above was actually stitched together from seven shots in Photoshop. In person, the area cleared looks much larger than it does above. Here’s another shot of the area taken from the air back in April that better shows its size.

*Photo of Phase 2 area (right) taken in April this near. Note the pipeline corridor (left of center) that bisects the property.*

About HCFCD’s Excavation and Removal Program

HCFCD has owned both portions of this site for years. They have been part of the District’s Excavation & Removal Program since 2005. The program lets contractors take and use dirt from the site for other projects outside of the floodplain – at no cost to the District or taxpayers.

Now, however, the Aldine-Westfield project is kicking into higher gear thanks to 2018 flood-bond dollars.

Details About Aldine Westfield Project

This two-phase stormwater detention basin will reduce the risk of flooding in the mid-reach stretch of Greens Bayou by taking in excess stormwater during heavy rain events and then releasing it slowly back to the channel when the threat of flooding has passed.

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 have enough capacity to hold a foot of rain falling over 2 square miles.

Phase 1 cost $7.4 million and Phase 2 will cost $12.2 million, for a total of almost $20 million.

Part of Larger Greens Bayou Plan

The Aldine Westfield Stormwater Detention Basin is part of a comprehensive flood risk reduction plan for the mid-reach stretch of Greens Bayou. That plan includes construction of 11 miles of channel conveyance improvements and four stormwater detention basins:

Aldine Westfield (Phase I complete; Phase II under construction)
Glen Forest (complete)
Kuykendahl (complete)
Lauder (Phase I near completion; Phase II under design)

This presentation, created a little more than a year ago, describes how the improvements discussed above will work in conjunction with several other subdivision and bayou drainage improvements.

The subdivision drainage improvements will be handled by the Harris County Engineering Department. They include increasing the capacity of storm sewers and curb inlets, repairing outfall pipes, and reconstructing roadside ditches. In the Humble area, subdivisions scheduled for the improvements include Fountainview Sections 1 & 2, Humble Road Place, and Parkland Estates. These subdivisions are just south of Beltway 8 near US59.

Areas Removed from 10- and 25-Year Floodplains

This community presentation from 2019 explains more about the benefits. It includes the two maps below.

*The light blue shows areas that will be REMOVED from the 10-year floodplain. The dark blue shows areas that will remain in it.*

*Likewise, light blue represents areas REMOVED from the 25-year floodplain.*

Posted by Bob Rehak on 10/15/2021

1508 days since Hurricane Harvey and 757 since Imelda

Lauder Detention Basin on Greens Bayou as of 10/12/2021

Phase I of Giant Lauder Detention Basin on Greens Bayou Nears Completion

Phase I of the giant Lauder Detention Basin on Greens Bayou is nearing completion. The 90-acre Phase I of the project will cost approximately $18 million when complete. Excavation and grading are now finished but landscaping still remains on the to-do list for most of the site. It’s come a long way since I photographed this project in July.

Harris County Flood Control District gave this project the name C34. It’s project ID is P500-06-00-E005. These alpha-numeric descriptions do little to communicate the beauty of this massive pond complex. See below.

Phase I Lauder Basin Photos Taken 10/12/21

*Looking south from over Greens Bayou (right).* *HCFCD contractors have begun to plant grass, but much still remains to plant including trees. Also, the ponds will have aquatic plants that improve water quality*.

*Looking north from north pond. Culverts will convey stormwater at a controlled rate from ponds to Greens Bayou at top of frame.* *The cut through the tree line by the bayou appears to be an overflow spillway.*

*Water flows from one pond into another within the 90-acre complex.*

*Looking south toward Lauder from north end of pond. That’s JFK Blvd. in the upper left.*

*Looking south from the Lauder Road entrance to the pond complex in Phase 1. That’s Aldine ISD’s Mead Middle School in the background.* *Note the drainage ditch running off into the distance and read the caption below.*

Looking north from Lauder Road. *Notice how water from the ditch above (P138-01-01 in map below) is channeled into ponds now at the lower left instead of going directly to Greens Bayou.* Also note excavation equipment being loaded on flatbed trucks for removal.

The Flood Control District has received an $11.5 million grant from the U.S. Natural Resources Conservation Service to help construct these ponds.

Phase II Still Being Designed

The detention basin shown above was purchased by the Flood Control District as undeveloped land in 2000. However, Phase II required buyouts.

*Looking west from over Phase I. Phase II when complete will occupy the wooded area in the upper right.*

Phase 1 is on right (E005), Phase 2 on left (E006). Phase 1 is in its final stages. Phase 2 is still in the design phase. Notice how each pond detains water from long channels before releasing it into Greens Bayou.

Phase II is immediately west of Phase I. It will be located on the property of the former Castlewood Subdivision, Sections 1 and 2. HCFCD completed preliminary engineering for Phase 2 in January 2021. The project is now in the design phase. It is budgeted for $20.5 million and scheduled to start construction in the summer of 2022.

Castlewood was built in the early 1960s in the Greens Bayou floodplain. It was also built in a former floodway of Greens Bayou before the bayou was rerouted and straightened circa the 1950s. Development occurred many years before the advent of Harris County’s first floodplain maps and associated development regulations in the 1980s. Since the late 1970s, there have been more than a dozen recorded flood events in the area.

*Artist’s rendering of pond layouts from HCFCD community presentation.* When complete, these basins will offer healthy recreational opportunities for area residents.

Together, Phases 1 & 2 comprise more than 200 acres – an area about 25% larger than Kingwood’s largest park – East End Park.

When complete, the ponds in both phases will have enough capacity to hold a foot of water falling across a two-square mile area. That’s water that won’t be going into Greens Bayou immediately during a big storm.

Posted by Bob Rehak on 10/14/2021

1507 Days since Hurricane Harvey

C-25, a Halls Bayou Detention pond now under construction by HCFCD

Another Massive Detention Pond Going In Next to Halls Bayou

Construction has begun on another massive detention pond along Halls Bayou. It stretches south from Isom Street to the bayou between Chrisman and Aldine-Westfield Roads. It covers approximately 26 acres and when complete will hold 180-acre feet of stormwater to reduce the risk of flooding. This is just one of 11 projects comprising the Halls Implementation Program. Together they have a total current value of $212 million dollars.

*Looking NNW across the new detention pond. Construction started in August 2021. HCFCD expects completion by March 2022.*

Such basins take in excess stormwater during heavy rain events and then release it slowly back to the channel when the threat of flooding has passed. Part of the basin will have a wet bottom and another part will have a vegetated shelf. Yet another part will go in between Isom and Aldine Mail Route Road, although that portion has not yet begun construction. (See below).

*Map on left shows current extent of construction work. Eventually, project will also include channel conveyance improvements (right) for a tributary that will be directed into the new pond.*

Harris County Flood Control District (HCFCD) lists the project as C-25 on its website. But the Flood Bond Program ID is P518-11-00. Ultimately, this will become part of a much larger project area that includes P118-21-00. Together, they will improve drainage in a large part of east Aldine.

Each of these projects falls into Commissioner Adrian Garcia’s Precinct 2. The description that accompanies the project in the flood-bond spreadsheet says, “This project could reduce the risk of flooding for over 90 buildings and could reduce the 1% floodplain for over 100 acres.” The HCFCD spreadsheet and website indicate a total cost of more than $14 million.

But keep this in mind. Project C-25 will work in conjunction with two proposed Harris County Engineering Department projects: neighborhood drainage improvements in the Western Homes subdivision and proposed roadway and drainage improvements along Aldine Mail Route Road. The detention capacity in the pond you see here will accommodate drainage improvements in those areas without flooding other areas. Thus, the pond will really help more than 90 structures.

*The project shown in these photos is P-518. P-118 is still in preliminary engineering review.*

C-25 is a partnership project. HCFCD received an approximately $9.5 million Community Development Block Grant for Disaster Recovery (CDBG-DR) from the US Department of Housing and Urban Development (HUD). Approximately $5.4 million comes from local funding.