Since 1998, the Brays Bayou watershed has received approximately a half billion dollars in flood-mitigation funding. To compile that estimate, I consulted Harris County Flood Control District’s (HCFCD) 2019 Federal Briefing (see page 45) and HCFCD’s “active construction projects” page for May 2021.
Map of Improvements
Nature of Improvements
The 2019 Federal Briefing (page 56) separates Brays improvements into two areas:
- Upstream (west of Sam Houston Tollway)
- 3 detention basins: 595 surface acres; 9,623 acre-feet of storage – enough to hold a foot of water falling over 15 square miles (13% of entire watershed)
- 3.7 miles of channel conveyance improvements, including control structures, from Old Westheimer Rd. to SH 6
- Downstream (east of Sam Houston Tollway)
- 17.5 miles of channel conveyance improvements from the mouth to Fondren Rd.
- 1 detention basin: 252 surface acres; 1,865 acre-feet of storage – enough to hold a foot of water falling over 3 square miles
- 30 bridge replacements/modifications, and/or channel conveyance improvements under bridges (16 due for completion this year)
Harris County Flood Control District (HCFCD) manages, designs, and builds the projects; buys land, easements, rights-of-way; relocates utilities; adjusts bridges (except for railroads); and operates and maintains the channel after construction.
Benefits and Costs
After completion, upstream improvements should give residents a 100-yr. level of flood protection (1% annual chance).
Likewise, downstream improvements should reduce the number of structures:
- In the 4% or 25-year flood plain from 3,520 to 50.
- In the 100-year flood plain from 16,800 to 1,800.
Total Cost Estimate: $480M though 2019 (Source: 2019 HCFCD Federal Briefing, Page 45)
Benefit-Cost Ratio: 7.0 (Source: 2019 HCFCD Federal Briefing, Page 56)
The size of the cost in conjunction with the benefit-cost ratio makes these numbers impressive. The primary requirement for the ratio is that it exceeds 1.0, i.e., that the benefits exceed the costs.
Brays’ watershed includes 114 square miles. That makes the cost per square mile a whopping $4.4 million throughout the watershed. However, one must also consider that the population of Brays is the largest of any watershed in Harris County – more than 700,000 of which (57.5%) qualifies as low-to-moderate income.
The map below, taken from a 2020 HCFCD grant application to the US Department of Housing and Urban Development (HUD), shows the distribution of income throughout the watershed. Areas such as West University and the Medical Center in the middle (blue) rank higher in income than areas east and west (tan/red).
Possible Reasons for Large Investment
You could justify this extraordinary level of investment any number of ways. By the:
- Large population
- High population density
- High benefit/cost ratio
- Protection of critical infrastructure, such as the Texas Medical Center
- Number of homes and businesses flooded historically – also the largest in Harris County: 32,194 structures since Allison (Source: 2019 Federal Briefing: Pages 16-21)
- Length of time projects have been in the pipeline (most before Harvey and some even before Allison)
- Proximity to older, central part of county
Do not underestimate the last two points. Funding for many flood-mitigation projects can take decades.
Regardless of the reasons why Brays has received so much investment, one can also look at what this example does not show. It does not support the “equity” narrative propounded by some. That narrative asserts low-to-moderate-income neighborhoods receive less flood-mitigation funding because of lower home values compared to more affluent neighborhoods. Those affluent neighborhoods theoretically get more flood-mitigation funding because they allegedly support higher benefit-cost ratios (BCRs).
Home Value Alone Does Not Determine Benefit/Cost Ratio
The 7.0 BCR in Brays proves that low-to-moderate income neighborhoods are not automatically disadvantaged. Population density can offset lower property values. A whole apartment complex can sit on the same amount of land as one suburban home, yet the apartments would have higher value.
Experts also point out that many other elements affect calculation of BCRs. This study from the William & Mary Law School summarizes the approaches of HUD, FEMA, the Corps and others in determining BCRs. Table I.1 on page 11 shows many of the factors considered:
- Resiliency benefits
- Direct Physical Damages to Buildings, Contents and Inventory
- Essential Facility and Critical Infrastructure Serivce Loss
- Human Impacts
- Economic Losses
- Environmental Benefits
- Provisioning Services
- Regulating Services
- Supporting Services
- Cultural Services
- Social Benefits
- Recreational Benefits
- Health Benefits
- Aesthetic Benefits
- Economic Revitalization
Brays Watershed Investment Not Suffering From Discrimination
The Brays watershed cuts across racial, ethnic and socio-economic boundaries. Flooding has been recognized as a problem here for decades and HCFCD has successfully obtained many grants during that time. HCFCD has also invested more in Brays than any other watershed. Like Halls Bayou and Greens Bayou, the narrative re: Brays is far more complex than some acknowledge.
Photos of Improvements in Bray’s Bayou Watershed
On May 26, I flew from Beltway 8 West to the Ship Canal east of downtown along Brays Bayou. Out of more than 1100 images, here are 16 that represent what you see along the way. Lots of detention ponds, channel improvements, and new bridges. The bridges are higher and often wider, with wider supports to avoid constrictions and blockages. New bridges never have more than two supports in the water flow; some old ones had seven.
As these pictures show, flood mitigation funding isn’t all about home value. Brays traverses some of Houston’s most critical infrastructure, job centers, rail lines, diverse neighborhoods and employment centers.
Posted by Bob Rehak on 6/3/2021
1374 Days since Hurricane Harvey