During Harvey, 16,000 homes and 3,300 businesses in the Lake Houston Area flooded. Local leaders identified the disparity in release capacities between the Lake Conroe and Lake Houston Dams as one of the contributing factors to the severity of flooding. The floodgates on Lake Conroe can release water 15 times faster than the gates on Lake Houston. So, adding more floodgates to Lake Houston became one of the area’s primary mitigation goals.
New gates would let the City rapidly lower the water level of Lake Houston in advance of a storm to prevent or reduce upstream flooding.
Lake Houston (l) and Lake Conroe gates (r). Conroe release capacity is 15X greater.
While the City of Houston initially obtained a $50 million grant from FEMA to add gates, two problems became apparent. The project cost more than anticipated and the benefits delivered did not justify the cost – at least the way FEMA was initially calculating them. However, a huge hurdle has been cleared.
The City of Houston has finally secured a favorable ruling from FEMA on a benefit-to-cost ratio, according to a press release from Mayor Pro Tem Dave Martin’s office on 12/7/2022. The key was the FEMA administrator’s decision to allow the inclusion of social benefits, for instance, avoidance of disruptions to business, commerce, schools and the area’s tax base. Those brought the BCR up to 2.88, according to Martin.
Martin, Mayor Sylvester Turner and Chief Recovery Officer Stephen Costello met with the Federal Emergency Management Agency (FEMA) Administrator to discuss the inequities of the Federal BCR formula associated with incorporation of social benefits.
As a result, Martin and Turner have announced that a large hurdle has been removed. The revised draft BCR for the Lake Houston Spillway Dam Improvement Project has been determined to be “federally compliant and is very favorable.”
The change affected the Lake Houston Gates and several other Houston stormwater projects including the massive, new Inwood Forest detention basin.
New BCR Based on Eleven Gates
Atkins, a City of Houston consultant, revised the BCR for an eleven-gate structure. The eleven gates will be built into the existing embankment on the east side of the Lake Houston Spillway Dam.
New gates would be added to the earthen portion of dam in foreground, not spillway at far end as originally planned.
Building the new gate structure in the east embankment removes the high construction risk of modifying the existing gate structure. It also allows continued use of the existing gate structure during construction, and eliminates the need for a coffer dam in the lake, according to Martin.
The new gates would likely align with the original course of the San Jacinto River, the channel on the left.
Cost Quadruples: Additional Funding Sources Now Necessary
The new preliminary cost estimate of $200 million exceeds the City’s original FEMA grant of $48 million.
Martin, Costello, and State Representative Dan Huberty have already met with the Texas House of Representatives Speaker Dade Phelan’s Director of Finance regarding additional funding. They have positioned the project as a “life and safety initiative” that affects the survival of the community and economy of the Lake Houston Area.
Martin has bi-partisan support already lined up for financing. Key partners this legislative session include:
Congressman Dan Crenshaw
State Senator Brandon Creighton
State Senator John Whitmire (who has already announced his intention to run for Houston mayor after Turner retires)
Speaker of the Texas House Dade Phelan
State Representative & Chair of Appropriations Dr. Greg Bonnen
State Representatives Charles Cunningham and Armando Walle.
Martin plans to work with Federal and State partners to ensure the cost of the Lake Houston Spillway Dam Project is fully funded before he leaves office in December 2023.
Said Martin, “Today a significant obstacle has been surpassed as this project moves forward through the financial process.” The new BCR should let federal, state, and local partners work toward fortifying the Lake Houston Area against future storms.
It would be unfair to call this a “start over.” A huge amount of engineering and analysis has gone into the project. However, challenges turned out to be greater than anyone anticipated after Harvey.
The original timetable from 12/16/19 showed the project completed by now. The fact that it is still alive is a tribute to the persistence of Martin, Turner, Costello and others.
Let’s look forward to the benefits, not backwards to the problems. People are working in the right direction. A huge obstacle has been eliminated. We just need to keep tackling new obstacles as they occur. Next step: the House and Senate.
I will post construction plans for the 11 gates and the Atkins’ BCR analysis as soon as the City supplies them; they promised they would.
Posted by Bob Rehak on 12/7/22
1926 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/12/20220722-RJR_0770-2.jpg?fit=1200%2C800&ssl=18001200adminadmin2022-12-07 10:55:302022-12-07 16:56:23City Gets Favorable Ruling on BCR for Lake Houston Gates Project
In the last 1924 days, I’ve researched, written, photographed and posted more than 2,093 stories about flooding and flood mitigation in the Houston region.
Recurring Themes Gradually Became Apparent
As I dug deeper and deeper into the causes of flooding, certain themes became apparent. They include, but are not limited to:
The complexity of coordinating federal, state, county and local governments to address watershed-level issues.
Fragmented and often conflicting priorities among local governments within the same watersheds.
Political processes that sometimes seem to favor growth over protection of existing residents.
Insufficiently mitigated upstream development that often offsets downstream mitigation investments.
Environmental destruction.
The tug-of-war for limited mitigation funding.
Disaster relief dollars that still can’t seem to find their intended targets.
The back-seat role that preservation and conservation often play.
People building in risky places using assumptions that later prove to be invalid.
I have hundreds of examples of each of these and more. Frankly, the examples are becoming too redundant. And their sheer volume deters new readers from getting the big picture.
Forest-For-The-Trees Dilemma Prompts Changes
It’s a classic forest-for-the-trees dilemma. There’s so much detail, it’s often hard to see the patterns. Therefore, changes are coming to ReduceFlooding.com.
Effective immediately, I’m going to start weaving those details into a book about flooding in Harris County. It will be a more manageable size than the website which now contains more than 1.5 million words and 8,785 images.
To make time for writing the book, I plan to cut back on daily website posts. Posts will become weekly or whenever major news breaks. So if you don’t see me everyday, please don’t think I’ve abandoned the cause.
I also hope to reorganize the website to make existing content support the themes above.
Sally Geis rescue during Harvey. North of Kingwood Drive about 8 feet above West Lake Houston Parkway.
Not Possible Without Your Support
My goal is to make all these changes before the start of next hurricane season. Thanks for all of your support during the last five years. Without your input, encouragement, and generous sharing of your experiences, none of this would have been possible. Together, we are documenting the many dimensions of flooding that may, just may, help reduce flooding in the future. Here and elsewhere.
Posted by Bob Rehak on 12/5/2022
1924 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2021/09/20170829-IMG_9819.jpg?fit=1200%2C900&ssl=19001200adminadmin2022-12-05 14:49:122022-12-05 21:58:40Changes Coming to ReduceFlooding.Com
Texas and Maryland represent opposite ends of the political spectrum. So, it’s not too surprising that floodplain regulations in the two areas differ radically. When it comes to building in harm’s way, most municipalities and counties in the Houston region allow development in the floodplain with certain precautions. But several counties in Maryland prohibit floodplain building altogether. One even requires developers to deed floodplain land to the county.
In contrast, Texas developers even fight for the right to build in floodways!
Looking E toward Lake Houston in distance along the floodway of the San Jacinto West Fork. Photo taken July 2020.
FEMA defines a floodway as the main channel of a river PLUS adjacent land that must remain free of development in order to avoid flooding areas upstream.
A floodplain extends farther out, usually to the edge of a valley. Floodplains flood repeatedly. Frequency and depth depend on rainfall and elevation within the floodplain. The area in the photo above flooded 53 times since Lake Houston was built 67 years ago. It even flooded SIX times in ONE year.
After Hurricane Harvey, Houston made its building regulations in floodplains more stringent. This table by the engineering firm WGA summarizes the changes.
“Zero net fill” prohibits elevating a home by bringing fill dirt in from outside the floodplain.
However, builders can still move dirt around inside the floodplain. They use a practice called “cut and fill.” Example: they take dirt out of a stormwater detention basin and use it to elevate slabs. That way they don’t reduce the area available to store floodwater.
These regulations do nothing to make homes already built in a floodplain safer. They only affect new building.
And they only make people safer to the extent that engineers can accurately predict the future. The future includes both rainfall and upstream development.
In the case of Harvey, remember that FEMA had revised flood maps just 10 years earlier. Now it’s revising them again.
The point: under the “there are ways to build here safely” philosophy, your “safety” is based on imperfect knowledge, changing conditions, changing regulations and shifting estimates.
Sample Maryland Regulations
Maryland takes a different approach to building in harm’s way. It says “Don’t.”
The State of Maryland provides model floodplain regulations. Section 4.2(b)1 states: “Subdivision proposals shall be laid out such that proposed building pads are located outside of the special flood hazard area and any portion of platted lots that include land areas that are below the base flood elevation shall be used for other purposes, deed restricted, or otherwise protected to preserve it as open space.”
Counties and Communities implement their own floodplain regulations. I haven’t checked every county, but found that Howard County:
Prohibits any new structures in the 100-year floodplain. See page 152.
Requires subdivisions to either a) deed land in floodplains to the county or b) grant floodplain easements to the county. (Page 136)
Prohibits storing building materials in a floodplain. (Page 136)
Prohibits clearing, excavating, filling or altering drainage in floodplains. (Page 136)
Will not issue variances for projects within floodways that result in any flood discharge levels (Page 139)
Montgomery County, Maryland, has prohibited residential development in 100-year floodplains since 2007. (Page 4).
The Texas philosophy says, “There are ways to build safely in flood-prone areas.” The Maryland philosophy seems to say, “It’s safer not to.”
It’s difficult to say objectively which is better/safer. The regulations are designed for different different people in different areas: Rural vs urban. Hilly vs. flat. Temperate vs. Subtropical.
But I will say this. As I read Howard County’s Hazard Mitigation Plan, the number of homes that could be damaged in a 100-year flood – ten – and a 500-year flood – twenty – shocked me. (Page 39). Compare that to the 154,000 structures damaged in Harris County during Harvey. Well, no, don’t. There is no comparison.
Posted by Bob Rehak on 12/4/2022
1923 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/2022/12/20200718-DJI_0150.jpg?fit=1200%2C900&ssl=19001200adminadmin2022-12-04 16:15:432022-12-04 16:56:20In Harm’s Way – To Build or Not to Build?
City Gets Favorable Ruling on BCR for Lake Houston Gates Project
During Harvey, 16,000 homes and 3,300 businesses in the Lake Houston Area flooded. Local leaders identified the disparity in release capacities between the Lake Conroe and Lake Houston Dams as one of the contributing factors to the severity of flooding. The floodgates on Lake Conroe can release water 15 times faster than the gates on Lake Houston. So, adding more floodgates to Lake Houston became one of the area’s primary mitigation goals.
While the City of Houston initially obtained a $50 million grant from FEMA to add gates, two problems became apparent. The project cost more than anticipated and the benefits delivered did not justify the cost – at least the way FEMA was initially calculating them. However, a huge hurdle has been cleared.
The City of Houston has finally secured a favorable ruling from FEMA on a benefit-to-cost ratio, according to a press release from Mayor Pro Tem Dave Martin’s office on 12/7/2022. The key was the FEMA administrator’s decision to allow the inclusion of social benefits, for instance, avoidance of disruptions to business, commerce, schools and the area’s tax base. Those brought the BCR up to 2.88, according to Martin.
Hurdle Removed: Project Now Federally Compliant
Earlier this summer, Martin announced challenges related to the Lake Houston Spillway Dam Improvement Project. The City needed to secure a benefit to cost ratio (BCR) between .75 and 1 and had examined multiple alternatives to find a favorable balance between costs and benefits.
Martin, Mayor Sylvester Turner and Chief Recovery Officer Stephen Costello met with the Federal Emergency Management Agency (FEMA) Administrator to discuss the inequities of the Federal BCR formula associated with incorporation of social benefits.
As a result, Martin and Turner have announced that a large hurdle has been removed. The revised draft BCR for the Lake Houston Spillway Dam Improvement Project has been determined to be “federally compliant and is very favorable.”
The change affected the Lake Houston Gates and several other Houston stormwater projects including the massive, new Inwood Forest detention basin.
New BCR Based on Eleven Gates
Atkins, a City of Houston consultant, revised the BCR for an eleven-gate structure. The eleven gates will be built into the existing embankment on the east side of the Lake Houston Spillway Dam.
Building the new gate structure in the east embankment removes the high construction risk of modifying the existing gate structure. It also allows continued use of the existing gate structure during construction, and eliminates the need for a coffer dam in the lake, according to Martin.
Cost Quadruples: Additional Funding Sources Now Necessary
The new preliminary cost estimate of $200 million exceeds the City’s original FEMA grant of $48 million.
Martin, Costello, and State Representative Dan Huberty have already met with the Texas House of Representatives Speaker Dade Phelan’s Director of Finance regarding additional funding. They have positioned the project as a “life and safety initiative” that affects the survival of the community and economy of the Lake Houston Area.
Martin has bi-partisan support already lined up for financing. Key partners this legislative session include:
Martin plans to work with Federal and State partners to ensure the cost of the Lake Houston Spillway Dam Project is fully funded before he leaves office in December 2023.
Said Martin, “Today a significant obstacle has been surpassed as this project moves forward through the financial process.” The new BCR should let federal, state, and local partners work toward fortifying the Lake Houston Area against future storms.
It would be unfair to call this a “start over.” A huge amount of engineering and analysis has gone into the project. However, challenges turned out to be greater than anyone anticipated after Harvey.
The original timetable from 12/16/19 showed the project completed by now. The fact that it is still alive is a tribute to the persistence of Martin, Turner, Costello and others.
Let’s look forward to the benefits, not backwards to the problems. People are working in the right direction. A huge obstacle has been eliminated. We just need to keep tackling new obstacles as they occur. Next step: the House and Senate.
I will post construction plans for the 11 gates and the Atkins’ BCR analysis as soon as the City supplies them; they promised they would.
Posted by Bob Rehak on 12/7/22
1926 Days since Hurricane Harvey
Changes Coming to ReduceFlooding.Com
In the last 1924 days, I’ve researched, written, photographed and posted more than 2,093 stories about flooding and flood mitigation in the Houston region.
Recurring Themes Gradually Became Apparent
As I dug deeper and deeper into the causes of flooding, certain themes became apparent. They include, but are not limited to:
I have hundreds of examples of each of these and more. Frankly, the examples are becoming too redundant. And their sheer volume deters new readers from getting the big picture.
Forest-For-The-Trees Dilemma Prompts Changes
It’s a classic forest-for-the-trees dilemma. There’s so much detail, it’s often hard to see the patterns. Therefore, changes are coming to ReduceFlooding.com.
Effective immediately, I’m going to start weaving those details into a book about flooding in Harris County. It will be a more manageable size than the website which now contains more than 1.5 million words and 8,785 images.
To make time for writing the book, I plan to cut back on daily website posts. Posts will become weekly or whenever major news breaks. So if you don’t see me everyday, please don’t think I’ve abandoned the cause.
I also hope to reorganize the website to make existing content support the themes above.
Not Possible Without Your Support
My goal is to make all these changes before the start of next hurricane season. Thanks for all of your support during the last five years. Without your input, encouragement, and generous sharing of your experiences, none of this would have been possible. Together, we are documenting the many dimensions of flooding that may, just may, help reduce flooding in the future. Here and elsewhere.
Posted by Bob Rehak on 12/5/2022
1924 Days since Hurricane Harvey
In Harm’s Way – To Build or Not to Build?
Texas and Maryland represent opposite ends of the political spectrum. So, it’s not too surprising that floodplain regulations in the two areas differ radically. When it comes to building in harm’s way, most municipalities and counties in the Houston region allow development in the floodplain with certain precautions. But several counties in Maryland prohibit floodplain building altogether. One even requires developers to deed floodplain land to the county.
In contrast, Texas developers even fight for the right to build in floodways!
The right to develop floodway land in the left foreground above was the subject of an eight-year lawsuit between a developer and the City of Houston.
Let’s examine the differences more closely.
Floodways vs. Floodplains
FEMA defines a floodway as the main channel of a river PLUS adjacent land that must remain free of development in order to avoid flooding areas upstream.
A floodplain extends farther out, usually to the edge of a valley. Floodplains flood repeatedly. Frequency and depth depend on rainfall and elevation within the floodplain. The area in the photo above flooded 53 times since Lake Houston was built 67 years ago. It even flooded SIX times in ONE year.
Houston Building Regulations
During Harvey, more than 150,000 structures in Harris County flooded. The area shown above went under 28 feet of water.
After Hurricane Harvey, Houston made its building regulations in floodplains more stringent. This table by the engineering firm WGA summarizes the changes.
The idea: by building higher, you build safer.
Regulations also address the foundation type and “fill” practices.
However, builders can still move dirt around inside the floodplain. They use a practice called “cut and fill.” Example: they take dirt out of a stormwater detention basin and use it to elevate slabs. That way they don’t reduce the area available to store floodwater.
These regulations do nothing to make homes already built in a floodplain safer. They only affect new building.
And they only make people safer to the extent that engineers can accurately predict the future. The future includes both rainfall and upstream development.
In the case of Harvey, remember that FEMA had revised flood maps just 10 years earlier. Now it’s revising them again.
The point: under the “there are ways to build here safely” philosophy, your “safety” is based on imperfect knowledge, changing conditions, changing regulations and shifting estimates.
Sample Maryland Regulations
Maryland takes a different approach to building in harm’s way. It says “Don’t.”
The State of Maryland provides model floodplain regulations. Section 4.2(b)1 states: “Subdivision proposals shall be laid out such that proposed building pads are located outside of the special flood hazard area and any portion of platted lots that include land areas that are below the base flood elevation shall be used for other purposes, deed restricted, or otherwise protected to preserve it as open space.”
Counties and Communities implement their own floodplain regulations. I haven’t checked every county, but found that Howard County:
Montgomery County, Maryland, has prohibited residential development in 100-year floodplains since 2007. (Page 4).
Frederick County, Maryland, states that no development has occurred in its floodplains in the past 10 years.
Two Different Philosophies
The Texas philosophy says, “There are ways to build safely in flood-prone areas.” The Maryland philosophy seems to say, “It’s safer not to.”
It’s difficult to say objectively which is better/safer. The regulations are designed for different different people in different areas: Rural vs urban. Hilly vs. flat. Temperate vs. Subtropical.
But I will say this. As I read Howard County’s Hazard Mitigation Plan, the number of homes that could be damaged in a 100-year flood – ten – and a 500-year flood – twenty – shocked me. (Page 39). Compare that to the 154,000 structures damaged in Harris County during Harvey. Well, no, don’t. There is no comparison.
Posted by Bob Rehak on 12/4/2022
1923 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.