Scott Elmer, P.E. CFM and Assistant Director of Operations for HCFCD, gave most of the presentation. A large part of it focused on the benefits of a flood tunnel system. The hour and twenty minute presentation contained more information than the presentation online. So, I will try to fill in some blanks for you.
Mr. Elmer talked extensively about “inherited flooding.” Much of Harris County, he says, developed before we fully understood flood risk and developed regulations to reduce it. For instance, he showed a series of three images around Halls Bayou and I-45.
#1 showed rural farmland.
#2 showed development starting near the bayou.
#3 showed development so dense that it would require buyouts before mitigation by conventional means.
Mr. Elmer then discussed the time, cost, and disruption of buying out enough properties to construct basins and widen channels. I posted about this last year in regard to the detention basins that straddle Halls at US59. Entire subdivisions had to be bought out before construction could begin. Each of those two basins took approximately a decade to finish, with most of the time consumed by buyouts.
Example of Ideal Location
Here’s an example of another location, farther up Halls between I-45 and Airline Drive.
One of the areas of heavy, repetitive flood damage in Harris County. Image from 1978. Area was farmland in the 1950s.
Many homes in this flat area are no more than a foot or two above the bayou banks. Some even sit below street level.
The entire area lies within some kind of flood hazard. And keep in mind, that this flood map was developed after Tropical Storm Allison in 2001. It does not even represent the risk under Atlas 14, the new flood probabilities developed after Harvey.
Tunnels represent an ideal complement to traditional solutions in such cases. They:
Expand options for flood damage reduction
Make the county’s stormwater network more robust
Reduce community disruption and increase resiliency
They make the most sense in areas where:
Land for traditional solutions is unavailable
Residential property acquisition would disrupt neighborhoods
Surface solutions would result in environmental impacts
Elmer presented a hypothetical situation to demonstrate equivalent risk reductions. Thirty-four acres required for tunnel construction could offset 3,145 acres of land needed for channel improvements and stormwater basins.
How Tunnel Locations Chosen
In describing how HCFCD chose the eight watersheds for further study, Elmer focused on:
Population density
Damage centers with high risk
Safety of lives
Strategic locations for intakes and outfalls
Identifying opportunities to integrate tunnels with other flood damage reduction measures
Avoiding geologic and man-made hazards, such as oil and water wells; or geologic faults.
As for the absence of tunnel recommendations on the eastern side of the county, Elmer simply said, other solutions would be more cost effective. He did not provide additional explanation.
Elmer’s presentation lasts a little more than half an hour.
A moderator describes the need for public comment before September 30 at 41:26.
Q&A begins 42:30.
The video ends at 1:18:00.
Items Not Covered
HCFCD gave no specific rationales for:
Locations of each of the eight tunnels.
Excluding large areas of the county.
I, for one, want to read the entire report before submitting my comments. But HCFCD has not made the report available online.
The presenters did not mention current flood risk in the respective locations. Nor did they say whether their recommendations accounted for recent flood mitigation investments.
Since 2000, the watersheds benefitting from the eight tunnels have already received 64 percent of all flood mitigation investments in Harris County. That includes partner spending. For instance:
Brays Bayou has received $575.3 million.
White Oak has received $526.3 million.
Sims Bayou has received $460 million.
Cypress and Little Cypress have received $442.5 million.
Greens has received $440 million.
Hunting and Halls have received $293.7 million.
Full Study Not Released
Before I vote on flood tunnels for these areas, I want to know how much flood risk remains compared to other areas that received less investment.
However, HCFCD has not yet released a study on the level of service (flood frequency likelihood) for every channel in the county.
The Phase 2 study just completed indicates we could spend $30 billion more on 132 miles of tunnels. That works out to almost a quarter billion dollars per mile.
Before I invest that much, I want to know how engineers arrived at these recommendations. Specifically, how much did politics enter into these decisions? The write up on HCFCD’s tunnel page makes it clear that “equity considerations” including the social vulnerability index weighed heavily.
I also want to know how the Cypress tunnel emptying into the San Jacinto West Fork between US59 and West Lake Houston Parkway would affect flooding in the heavily populated Humble/Kingwood Area.
Public Comment Period Lasts Through September 30
If you wish to submit public comments on the flood tunnels, you have until September 30, 2022. Submit comments at Public Input.com/tunnels. I intend to request the entire engineering study and will post more when I learn how HCFCD made the recommendations.
Posted by Bob Rehak
1755 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/06/Screen-Shot-2022-06-19-at-5.15.23-PM.png?fit=2452%2C1366&ssl=113662452adminadmin2022-06-19 18:41:182022-06-21 15:32:54HCFCD Recommends More Study for $30 Billion Flood Tunnels
Harris County Flood Control District (HCFCD) has set the demolition dates for two of the three remaining Forest Cove Townhome complexes. The two farthest from the river will be torn down on 7/5/22 and 7/14/22. See image below.
On 6/17/22, HCFCD also deposited the check for the buyout of the last unit in the last complex. So, according to HCFCD spokesperson, Amy Stone, “The final demolition should be scheduled soon!”
Demolition dates for the three remaining Forest Cove Townhome complexes.San Jacinto West Fork at top of frame. Forest Cove Community Center and swimming pool on right.
Reason for Delays
Buying out close to 100 units destroyed by Harvey has been a tortuous and time-consuming process. Several of the owners, unable to live in the townhomes, reportedly walked away from their properties, leaving them in limbo. In the process, they created a blight on the community that became a magnet for drug dealing, illegal dumping, vandalism, arson, and graffiti.
I talked to an angry Forest Cove resident this morning who can’t wait for the last remaining units to be demolished.
Photos Taken on 6/18/22
Here are some photos taken this morning from ground and air showing the condition of the last units still standing.
Two complexes scheduled for demolition on 7/5 and 7/14.Same complexes from the ground.Last complex, not yet scheduled for demolitionSame complex from ground level.
Back to Green Space
HCFCD usually lets such buyout areas return to green space and has announced its intention to do the same here. However, it’s not yet clear exactly what that means. Flood Control has not yet responded to a request for specific plans.
Nevertheless, the Houston Parks Board has already begun a trail along the West Fork. It currently reaches from the Kingwood trail system at River Grove Park to Marina Drive in Forest Cove, shown below. It now terminates behind the two complexes already scheduled for demolition in July.
Terminus of Houston Parks Board San Jacinto Greenway at Marina Drive, approximately 2.6 miles from River Grove Park as the crow flies.
Planned route of trail connecting Woodland Hills Drive to 59 and Spring Creek Trail.Green = completed. Purple = planned.
Someday soon, this area could become a huge asset to the Kingwood/Forest Cove/Lakewood Cove community again.
Posted by Bob Rehak on 6/18/22
1754 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/06/20220618-RJR_9535.jpg?fit=1200%2C800&ssl=18001200adminadmin2022-06-18 12:34:142022-06-18 12:49:50Demolition Dates Set for Forest Cove Townhomes
This morning, Harris County Meteorologist Jeff Lindner sent me an email that caused me to worry. It wasn’t about flooding. It was about our dismal rain chances for the next two weeks.
His email also contained a map of all the outdoor burn bans in effect across the state. Of 254 counties in Texas, 133 currently ban burns.
According to the Texas A&M Forest Service, more than half of Texas counties have burn bans in effect.
We’ve had the 8th driest year to date in the last 128 years.
So why worry about flooding now? Here are my top three reasons. You may have others.
Repetitive Cycles
Previously, Lindner sent a separate email comparing 2022 with 2011, the start of our last major drought. Within it, he said, “While it is easy to compare heat and drought to other instances in the past, our current heat and drought is far from what this region and state went through in 2011. Rainfall has been much more plentiful this spring than in 2011, and while some of the temperatures may be similar, the intensity of the heat thus far this year is not to the level of 2011. There are some similar comparisons to drought and heat of the summers of 1998, 1988, and 1980.”
The drought years caught my eye. I asked him if there was a reason for the relative regularity.
He replied, “Generally speaking … a lot of our heat/drought and floods correlate with El Niño and La Niña in the central and eastern Pacific. La Niña years tend to favor heat and drought in the southern plains, though not always. 2011 was one of the strongest La Niñas on record since 1950. On the other hand, El Niño tends to favor cooler and wetter periods. Many of our big floods have happened in El Nino years.”
Knowing that floods follow droughts in regular cycles (and that floods could happen at any time from a stray tropical storm), you never want to be lulled into a false sense of security about flooding.
Complacency
Droughts can create complacency about flooding. People forget the pain. Political pressure and attention shift to more pressing problems, such as crime or Covid. And after two years of lockdown, people are ready for vacation, even with $5/gallon gasoline! But like the parable of the Three Little Pigs, people who live in SE Texas can never become complacent about flood threats. Flooding is our #1 natural disaster.
SJRA started a program of lowering Lake Conroe to reduce downstream flooding risk during the rainiest months of spring and hurricane season. But how many people know the policy was modified this year to raise the minimum levels?
FEMA, HUD and the GLO sent billions of dollars to Houston And Harris County for disaster relief and flood mitigation. Do you know how much has actually helped people?
Apathy when we’re not flooding could sow the seeds of the next big flood. Vigilance is the price of freedom…from flooding, too.
Unintended Consequences
Most research on hydrological risks focuses either on flood risk or drought risk. However, floods and droughts are two extremes of the same hydrological cycle. They are inextricably linked. One follows the other like night follows day.
Strategies targeted at one may create unintended consequences for the other. So, it is important to consider interactions between these closely linked phenomena.
For instance, drought can decrease groundwater, kill ground cover, and increase erosion. Erosion can create sediment dams that contribute to flooding. We knew giant sand bars like the one below were likely to form in the headwaters of Lake Houston since the 1990s. But our mayors at the time refused to dredge. Even though there was no imminent threat, that turned out to be a costly decision.
The West Fork San Jacinto mouth bar in the headwaters of Lake Houston in 2018. Before/after measurements show that as much as ten feet was deposited in this area during Harvey (five below water/five above).This and other bars have since been dredged, but the Army Corps said they blocked the river 90%.
I could list more examples. But you get the idea. Even though another Harvey is not lingering offshore at the moment, how much have we really learned? How much have actually improved conditions that increased flood risk during Harvey?
Please stay in the fight to make our homes, businesses and community safer.
Posted by Bob Rehak on 5/17/22
1753 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.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2018/03/Harvey-SanJac_217.jpg?fit=2000%2C1333&ssl=113332000adminadmin2022-06-16 19:10:122022-06-16 19:21:16Why Worry about Flooding in a Drought?
HCFCD Recommends More Study for $30 Billion Flood Tunnels
(Update: Since posting this story, HCFCD has provided a link to the entire 1860-page flood tunnel study online.)
On June 16, 2022, Harris County Flood Control District (HCFCD) held a virtual meeting to present the results of Phase 2 of its flood-tunnels study. Phase 2 recommended eight tunnels estimated to cost $30 billion for further study. The purpose of Phase 3: to advance the design far enough to quantify the benefits and validate cost assumptions in order to apply for grants that would help offset costs.
The secondary purpose of the meeting: to gage public support for tunnels, none of which would benefit the Lake Houston Area.
Below, see a brief summary of the one hour and twenty minute meeting.
Watersheds Where Tunnels Being Considered
Phase 2 recommended additional study for tunnels in the following watersheds:
The conveyance of all eight projects would TOTAL approximately 75,000 cubic feet per second (CFS). To put that in perspective, that’s approximately 4,000 CFS less than the SJRA released from Lake Conroe during Harvey.
Potential Advantages of Tunnel System
Scott Elmer, P.E. CFM and Assistant Director of Operations for HCFCD, gave most of the presentation. A large part of it focused on the benefits of a flood tunnel system. The hour and twenty minute presentation contained more information than the presentation online. So, I will try to fill in some blanks for you.
Mr. Elmer talked extensively about “inherited flooding.” Much of Harris County, he says, developed before we fully understood flood risk and developed regulations to reduce it. For instance, he showed a series of three images around Halls Bayou and I-45.
Mr. Elmer then discussed the time, cost, and disruption of buying out enough properties to construct basins and widen channels. I posted about this last year in regard to the detention basins that straddle Halls at US59. Entire subdivisions had to be bought out before construction could begin. Each of those two basins took approximately a decade to finish, with most of the time consumed by buyouts.
Example of Ideal Location
Here’s an example of another location, farther up Halls between I-45 and Airline Drive.
Many homes in this flat area are no more than a foot or two above the bayou banks. Some even sit below street level.
The entire area lies within some kind of flood hazard. And keep in mind, that this flood map was developed after Tropical Storm Allison in 2001. It does not even represent the risk under Atlas 14, the new flood probabilities developed after Harvey.
Harris County’s Flood Warning System shows Halls has come out of its banks at Airline Drive at least 12 times since 1984. Yet there is very little room to widen the channel or build detention basins.
Best Locations for Tunnels
Tunnels represent an ideal complement to traditional solutions in such cases. They:
They make the most sense in areas where:
Elmer presented a hypothetical situation to demonstrate equivalent risk reductions. Thirty-four acres required for tunnel construction could offset 3,145 acres of land needed for channel improvements and stormwater basins.
How Tunnel Locations Chosen
In describing how HCFCD chose the eight watersheds for further study, Elmer focused on:
As for the absence of tunnel recommendations on the eastern side of the county, Elmer simply said, other solutions would be more cost effective. He did not provide additional explanation.
For Elmer’s full presentation, click here.
To see a YouTube Video of this entire presentation including the Q&A that followed, click here. The meat of the presentation starts at about 8 minutes and 30 seconds into the video.
Items Not Covered
HCFCD gave no specific rationales for:
I, for one, want to read the entire report before submitting my comments. But HCFCD has not made the report available online.
Since 2000, the watersheds benefitting from the eight tunnels have already received 64 percent of all flood mitigation investments in Harris County. That includes partner spending. For instance:
Full Study Not Released
Before I vote on flood tunnels for these areas, I want to know how much flood risk remains compared to other areas that received less investment.
However, HCFCD has not yet released a study on the level of service (flood frequency likelihood) for every channel in the county.
The Phase 2 study just completed indicates we could spend $30 billion more on 132 miles of tunnels. That works out to almost a quarter billion dollars per mile.
Before I invest that much, I want to know how engineers arrived at these recommendations. Specifically, how much did politics enter into these decisions? The write up on HCFCD’s tunnel page makes it clear that “equity considerations” including the social vulnerability index weighed heavily.
I also want to know how the Cypress tunnel emptying into the San Jacinto West Fork between US59 and West Lake Houston Parkway would affect flooding in the heavily populated Humble/Kingwood Area.
Public Comment Period Lasts Through September 30
If you wish to submit public comments on the flood tunnels, you have until September 30, 2022. Submit comments at Public Input.com/tunnels. I intend to request the entire engineering study and will post more when I learn how HCFCD made the recommendations.
Posted by Bob Rehak
1755 Days since Hurricane Harvey
Demolition Dates Set for Forest Cove Townhomes
Harris County Flood Control District (HCFCD) has set the demolition dates for two of the three remaining Forest Cove Townhome complexes. The two farthest from the river will be torn down on 7/5/22 and 7/14/22. See image below.
On 6/17/22, HCFCD also deposited the check for the buyout of the last unit in the last complex. So, according to HCFCD spokesperson, Amy Stone, “The final demolition should be scheduled soon!”
Reason for Delays
Buying out close to 100 units destroyed by Harvey has been a tortuous and time-consuming process. Several of the owners, unable to live in the townhomes, reportedly walked away from their properties, leaving them in limbo. In the process, they created a blight on the community that became a magnet for drug dealing, illegal dumping, vandalism, arson, and graffiti.
I talked to an angry Forest Cove resident this morning who can’t wait for the last remaining units to be demolished.
Photos Taken on 6/18/22
Here are some photos taken this morning from ground and air showing the condition of the last units still standing.
Back to Green Space
HCFCD usually lets such buyout areas return to green space and has announced its intention to do the same here. However, it’s not yet clear exactly what that means. Flood Control has not yet responded to a request for specific plans.
Nevertheless, the Houston Parks Board has already begun a trail along the West Fork. It currently reaches from the Kingwood trail system at River Grove Park to Marina Drive in Forest Cove, shown below. It now terminates behind the two complexes already scheduled for demolition in July.
The Parks Board has plans to take this trail all the way to US59 eventually.
Someday soon, this area could become a huge asset to the Kingwood/Forest Cove/Lakewood Cove community again.
Posted by Bob Rehak on 6/18/22
1754 Days since Hurricane Harvey
Why Worry about Flooding in a Drought?
This morning, Harris County Meteorologist Jeff Lindner sent me an email that caused me to worry. It wasn’t about flooding. It was about our dismal rain chances for the next two weeks.
His email also contained a map of all the outdoor burn bans in effect across the state. Of 254 counties in Texas, 133 currently ban burns.
Texas’ drought monitor website shows that as of 6/15/22:
So why worry about flooding now? Here are my top three reasons. You may have others.
Repetitive Cycles
Previously, Lindner sent a separate email comparing 2022 with 2011, the start of our last major drought. Within it, he said, “While it is easy to compare heat and drought to other instances in the past, our current heat and drought is far from what this region and state went through in 2011. Rainfall has been much more plentiful this spring than in 2011, and while some of the temperatures may be similar, the intensity of the heat thus far this year is not to the level of 2011. There are some similar comparisons to drought and heat of the summers of 1998, 1988, and 1980.”
The drought years caught my eye. I asked him if there was a reason for the relative regularity.
He replied, “Generally speaking … a lot of our heat/drought and floods correlate with El Niño and La Niña in the central and eastern Pacific. La Niña years tend to favor heat and drought in the southern plains, though not always. 2011 was one of the strongest La Niñas on record since 1950. On the other hand, El Niño tends to favor cooler and wetter periods. Many of our big floods have happened in El Nino years.”
Knowing that floods follow droughts in regular cycles (and that floods could happen at any time from a stray tropical storm), you never want to be lulled into a false sense of security about flooding.
Complacency
Droughts can create complacency about flooding. People forget the pain. Political pressure and attention shift to more pressing problems, such as crime or Covid. And after two years of lockdown, people are ready for vacation, even with $5/gallon gasoline! But like the parable of the Three Little Pigs, people who live in SE Texas can never become complacent about flood threats. Flooding is our #1 natural disaster.
After Harvey, flooding floated to the top of Houstonians’ concerns. We launched massive mitigation efforts. But do you know where they stand today?
Apathy when we’re not flooding could sow the seeds of the next big flood. Vigilance is the price of freedom…from flooding, too.
Unintended Consequences
Most research on hydrological risks focuses either on flood risk or drought risk. However, floods and droughts are two extremes of the same hydrological cycle. They are inextricably linked. One follows the other like night follows day.
Strategies targeted at one may create unintended consequences for the other. So, it is important to consider interactions between these closely linked phenomena.
For instance, drought can decrease groundwater, kill ground cover, and increase erosion. Erosion can create sediment dams that contribute to flooding. We knew giant sand bars like the one below were likely to form in the headwaters of Lake Houston since the 1990s. But our mayors at the time refused to dredge. Even though there was no imminent threat, that turned out to be a costly decision.
I could list more examples. But you get the idea. Even though another Harvey is not lingering offshore at the moment, how much have we really learned? How much have actually improved conditions that increased flood risk during Harvey?
Please stay in the fight to make our homes, businesses and community safer.
Posted by Bob Rehak on 5/17/22
1753 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.