11/4/2025 – FEMA floodplain maps contradict a claim made by Scarborough Development/San Jacinto Preserve in a presentation made to the City of Houston and Harris County officials on 10/29/25.
The developer recently bought 5,316 acres, mostly in the floodplains and floodways of Spring and Cypress Creeks, and the San Jacinto West Fork. The land lies in both Montgomery County and the City of Houston’s extra territorial jurisdiction. The developer also wants to build a bridge into Harris County.
However, superimposing their development plan on FEMA’s current floodplain maps developed before Atlas 14 contradicts that claim. Why?
The extent of proposed development matches the limits of pre-, not post-, Atlas 14 100-year floodplains.
Net: developing in this area is more dangerous than it may look. 500-year floodplains could soon become 100-year floodplains.
For more detail, see the discussion of Atlas-14’s history and the sequence of maps below.
A Brief History of Atlas 14
FEMA’s current floodplain maps for this area date to 2014, four years BEFORE the start of Atlas 14 in Texas. And to my knowledge, FEMA has not yet released new flood maps based on Atlas 14 for this region.
NOAA began updating rainfall precipitation frequency estimates in 2004; they called the effort “Atlas 14.” But NOAA didn’t update Texasstatistics until 2018. Such rainfall estimates form the basis for flood maps.
In Montgomery County (MoCo), pre/post estimates for the standard 100-year/24-hour rainfall varied by more than a third. MoCo adopted Atlas 14 values of ~16.1 inches for the 24-hr, 1% storm (at Conroe), up from the previous standard of ~12 inches. That’s an increase of 4.1 inches or 34%.
Also consider that Montgomery County has been one of the fastest growing counties in the region and in America. Its population has grown by almost a third (31%) since 2018. That population growth comes with a growth of impervious cover (roofs, driveways, streets, parking lots, etc.) that doesn’t soak up rainfall.
I’m not aware of any recent studies that show the cumulative impact of additional rainfall and impervious cover together with a deficit of detention.
Given those issues, common sense says flood elevations would increase. And in fact, preliminary guidance from Harris County indicates that floodplains will expand by 50% to 100% when FEMA releases updated flood maps based on Atlas 14.
New Plans Show Development Extending to Old 100-Year Floodplain
When I first saw the developer’s new plans, the plans didn’t seem to match the claim that they would only develop land “at or above the Atlas 14 100-year floodplain.” That made me suspicious. So, I performed an experiment.
I superimposed the developer’s plans over FEMA’s current (pre-Atlas 14) map dated 2014. I then varied the opacity of the layers in Adobe Photoshop so I could see how the two matched up. Long story short, they matched perfectly. See the sequence of images below.
Layer 1: From FEMA’s Flood Hazard Layer Viewer. Scarborough property is in center between Spring Creek (diagonal) and West Fork (right). Brown areas = 500-year floodplain. Aqua = 100-year. Striped = floodway.
Next, I superimposed the development plan that Scarborough presented to City of Houston and Harris County.
Layer 2: Gray areas with waffle pattern represent claimed “net developable area.”Red = property boundary.
Then, I varied the opacity of the development plan until you could see the floodplains behind it.
Composite with partial transparency of overlay
Enlargement clearly shows thatdevelopment stops at the old, pre-Atlas-14, 100-year floodplain.
White lines from 2014 FEMA map form boundary between 100- and 500-year floodplains. And waffle patterns from developer’s plans stop at white lines.
New maps reflecting higher rainfall rates and more impervious cover will likely show those white lines cutting well into the brown so-called developable areas, if not eliminating some altogether.
Where Did Developer’s Claim Come From?
So, where did the developer’s Atlas 14 claim come from? I have talked to three people who were in the meeting. Not one could tell me with certainty. They all expressed reservations and doubts about it.
I have also reached out to Scarborough several times to understand their position, but they have yet to return phone calls or emails.
So, I’m going to remain skeptical until I see proof of their claim and FEMA’s new Atlas 14 maps. FEMA may release them in 2026. But the proposed maps will then go through public comment and revision cycles. That could mean they won’t become official for at least another three years.
Make This An Election Issue
In my opinion, the best use for this property would be to turn it into a state park. That would help protect areas both up and downstream. With an election coming up next year, our representatives will have their ears to the ground. The time to start a letter-writing campaign is now. Contact all candidates.
Turn this into an election issue.
Make sure we elect someone who is more interested in protecting public safety than private profits.
Posted by Bob Rehak on 11/4/25
2989 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/2025/11/20251103-CU-of-Southern-Area.jpg?fit=1100%2C561&ssl=15611100adminadmin2025-11-04 12:01:042025-11-04 14:53:30Floodplain Maps for 5,316 Acres West of Kingwood Contradict Developer’s Claim
11/2/25 – Hurricane Melissa disappeared off the tracking charts yesterday. And when it did, one of the most powerful storms in recorded history went into the history books.
Many things made Melissa unusual and stunned meteorologists. They included the storm’s deep pressure, high winds, rapid intensification, death toll, destruction, and its timing within the hurricane season.
And all of that happened in a season that has, so far, spared the U.S. mainland from any landfalling hurricanes.
A Normal Season
Usually, the Atlantic Hurricane season is largely over by the end of October.
One tropical storm, but no hurricanes have hit the US mainland so far this year.
In May this year, NOAA predicted an above average season with 13-19 named storms, of which 6-10 would become hurricanes, including 3-5 major hurricanes.
So far, we’ve had 13 named storms. Five became hurricanes, four of which reached major hurricane strength. See below.
Why So Strong, So Late?
First, we had very warm waters in the Caribbean – 1.9ºC to 2.8ºC above average for the region and season. That’s up to 5º F warmer than average.
More importantly: the warm layer extended to depth — meaning the storm could churn up deeper water without encountering cooler up-welled water that normally weakens storms.
Second, reduced wind sheer and steering currents caused it to meander slowly. This helped it sit over very warm waters while enhancing its strength.
Melissa underwent two rounds of rapid intensification, including a gain of ~70 mph in 24 hours — an “extreme rapid intensification” event. Because water was abnormally warm for that late in the season, and other inhibiting factors were low, the conditions aligned for a major hurricane even though the calendar was later.
Sea surface temperatures ordinarily decline and atmospheric conditions become less favorable this late in the season. But not this year. So, Melissa could reach peak strength even in late October. Some scientists hypothesize that climate change may have played a role. Others believe it was just the random confluence of favorable factors.
Warm water is necessary but not sufficient to create a major hurricane. In this case, the atmosphere cooperated, which is part of why Melissa could intensify so late and so rapidly.
Typically by late October, conditions become less favorable for hurricane formation (cooler oceans, increasing shear, etc.).
ABC News reported that at least two hurricane-hunter aircraft had to turn back from Hurricane Melissa due to extreme turbulence: one from the U.S. Air Force Reserve 53rd Weather Reconnaissance Squadron and another from NOAA.
Melissa’s Eye. U.S. Air Force photo by Lt. Col. Mark Withee on Oct. 27, 2025.
Melissa made landfall in Jamaica with sustained winds of 185 mph, tying it for the strongest Atlantic hurricane landfall by wind speed. (Wikipedia+4AP News+4CBS News+4).
A scientist from the University of Miami onboard the Hurricane Hunter recorded a spot wind gust of 252 MPH. If verified, it will be the highest speed ever recorded in a tropical cyclone by a dropsonde. That rivals winds in EF5 tornadoes!
Melissa also recorded a central pressure of 892 mb, tying the record for third‐lowest minimum central pressure in the Atlantic basin. (CT Insider+1).
So far, Melissa is the strongest tropical cyclone of any kind worldwide in 2025.
USA Today reported today that the storm left more than 60 people dead in Haiti, Jamaica and the Dominican Republic.
Posted by Bob Rehak on 11/2/25
2987 Days since Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2025/11/20251102-Melissas-Eye.jpg?fit=1100%2C818&ssl=18181100adminadmin2025-11-02 20:30:042025-11-02 20:30:05How Could Hurricane Melissa Get So Strong So Late in the Season?
11/1/2025 – On 10/28/25, members of the Harris County Community Flood Resilience Task Force received a brief presentation about how flood-mitigation projects get prioritized by Harris County.
Below are several key slides from “Overview & History of the 2018 Bond Program’s Prioritization Framework.”
How Prioritization Started
Before the 2018 bond election on the anniversary of Hurricane Harvey, language was inserted into the proposal that voters went on to approve. Specifically, note Paragraph 14G. It called for developing a process for the “equitable expenditure of funds.”
Another year later, the county (under the guise of Harris Thrives) adopted two resolutions. The first instructed Harris County Flood Control District to adopt a framework for the equitable expenditure of Bond Program funds. The second set up a community-based Task Force.
“Harris Thrives” is the name of a resilience strategy adopted by Harris County after Harvey. It claims to be a “fast, fair, smart” approach to flood control, but also includes housing. Specifically it claims the county will be:
Fast: Cutting through red tape to complete flood-control projects quickly.
Fair: Prioritizing projects to help the most people as efficiently as possible, while ensuring vulnerable communities are never left behind.
Smart: Relying on science, technology, and data as a guide to be more proactive about how mitigation, preparation, and recovery.
Broad: Including programs for housing recovery, emergency preparedness, and community engagement.
Admirable goals. But it appears that Harris Thrives’ website has not been updated since February 2023, despite a promise to update it quarterly at that time. Only history and the Freedom of Information Act will tell us whether the county achieved those goals.
How Prioritization Framework Evolved
The Framework has gone through several iterations over time as commissioners’ priorities have changed.
After Harvey, the focus was speed.
Two years later, the focus was prioritizing certain projects and de-emphasizing others.
Five years later, the focus became tweaking the framework to ensure dollars went where commissioners wanted.
Six years later, commissioners asked HCFCD to rank projects already initiated into quartiles to ensure pet projects could be fully funded.
Eight years later, it became clear there wasn’t enough money to do all the projects promised in the flood bond. So commissioners voted to focus on projects in the top quartile.
Under previous management, HCFCD updated the status of every project for every commissioners court meeting. And those updates were posted online.
But since a change in management and priorities in 2022, it has been hard to identify where projects, budgets, and construction stands. Bond updates became annual as projects slowed to a crawl.
The old, simple-but-effective text-based lists with GANTT charts have been replaced by a series of somewhat confusing dashboards that work occasionally and with mixed effectiveness in different browsers.
Clicking on the dots calls up information about the associated project. But gone are the old, intuitive Gantt charts that gave you timing, lifecycle, and status information at a glance.
Sigh. At least they’re trying. And in fairness, they are improving. The Microsoft PowerBI spending charts on the HCFCD Activity Page are a valuable addition, even though that information is updated quarterly.
Changing Priorities
Through the years, priorities changed. The presentation showed the current scoring matrix.
2022 scoring matrix
However, it did not show the scoring matrix in the original 2019 Prioritization Framework. See below.
2019 scoring matrix
Comparison shows that flood-risk reduction and partnership funding (combined weight of 35%) have been eliminated from consideration. In their place, population and housing density (aka project efficiency) have increased by a similar amount. That favors projects near the city center, but eliminates severity of flooding as a consideration, which is why the largest watershed in the county with the worst flooding has received only 2% of spending to date.
Eliminating partnership funding is a curious switch, too, especially since more than half of bond-project funding relies on matching partnership dollars.
Search on the tag “equity prioritization” in the search bar of this website.
Posted by Bob Rehak on 11/1/25
2986 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2025/11/Prioritization-Priorities-scaled.png?fit=2560%2C1401&ssl=114012560adminadmin2025-11-01 16:22:312025-11-01 16:22:32Evolution of Harris County Flood-Project Prioritization
Floodplain Maps for 5,316 Acres West of Kingwood Contradict Developer’s Claim
11/4/2025 – FEMA floodplain maps contradict a claim made by Scarborough Development/San Jacinto Preserve in a presentation made to the City of Houston and Harris County officials on 10/29/25.
The developer recently bought 5,316 acres, mostly in the floodplains and floodways of Spring and Cypress Creeks, and the San Jacinto West Fork. The land lies in both Montgomery County and the City of Houston’s extra territorial jurisdiction. The developer also wants to build a bridge into Harris County.
In documents obtained from the City of Houston, the developer claimed it would only be “developing land at or above the Atlas 14 100-year floodplain.” See copy in red box below.
However, superimposing their development plan on FEMA’s current floodplain maps developed before Atlas 14 contradicts that claim. Why?
Net: developing in this area is more dangerous than it may look. 500-year floodplains could soon become 100-year floodplains.
For more detail, see the discussion of Atlas-14’s history and the sequence of maps below.
A Brief History of Atlas 14
FEMA’s current floodplain maps for this area date to 2014, four years BEFORE the start of Atlas 14 in Texas. And to my knowledge, FEMA has not yet released new flood maps based on Atlas 14 for this region.
NOAA began updating rainfall precipitation frequency estimates in 2004; they called the effort “Atlas 14.” But NOAA didn’t update Texas statistics until 2018. Such rainfall estimates form the basis for flood maps.
In Montgomery County (MoCo), pre/post estimates for the standard 100-year/24-hour rainfall varied by more than a third. MoCo adopted Atlas 14 values of ~16.1 inches for the 24-hr, 1% storm (at Conroe), up from the previous standard of ~12 inches. That’s an increase of 4.1 inches or 34%.
Just as important, until earlier this year, MoCo drainage regulations often let developers avoid building stormwater detention basins that would offset that additional rainfall.
Also consider that Montgomery County has been one of the fastest growing counties in the region and in America. Its population has grown by almost a third (31%) since 2018. That population growth comes with a growth of impervious cover (roofs, driveways, streets, parking lots, etc.) that doesn’t soak up rainfall.
I’m not aware of any recent studies that show the cumulative impact of additional rainfall and impervious cover together with a deficit of detention.
Given those issues, common sense says flood elevations would increase. And in fact, preliminary guidance from Harris County indicates that floodplains will expand by 50% to 100% when FEMA releases updated flood maps based on Atlas 14.
New Plans Show Development Extending to Old 100-Year Floodplain
When I first saw the developer’s new plans, the plans didn’t seem to match the claim that they would only develop land “at or above the Atlas 14 100-year floodplain.” That made me suspicious. So, I performed an experiment.
I superimposed the developer’s plans over FEMA’s current (pre-Atlas 14) map dated 2014. I then varied the opacity of the layers in Adobe Photoshop so I could see how the two matched up. Long story short, they matched perfectly. See the sequence of images below.
Next, I superimposed the development plan that Scarborough presented to City of Houston and Harris County.
Then, I varied the opacity of the development plan until you could see the floodplains behind it.
Enlargement clearly shows that development stops at the old, pre-Atlas-14, 100-year floodplain.
New maps reflecting higher rainfall rates and more impervious cover will likely show those white lines cutting well into the brown so-called developable areas, if not eliminating some altogether.
Where Did Developer’s Claim Come From?
So, where did the developer’s Atlas 14 claim come from? I have talked to three people who were in the meeting. Not one could tell me with certainty. They all expressed reservations and doubts about it.
I have also reached out to Scarborough several times to understand their position, but they have yet to return phone calls or emails.
So, I’m going to remain skeptical until I see proof of their claim and FEMA’s new Atlas 14 maps. FEMA may release them in 2026. But the proposed maps will then go through public comment and revision cycles. That could mean they won’t become official for at least another three years.
Make This An Election Issue
In my opinion, the best use for this property would be to turn it into a state park. That would help protect areas both up and downstream. With an election coming up next year, our representatives will have their ears to the ground. The time to start a letter-writing campaign is now. Contact all candidates.
Make sure we elect someone who is more interested in protecting public safety than private profits.
Posted by Bob Rehak on 11/4/25
2989 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.
How Could Hurricane Melissa Get So Strong So Late in the Season?
11/2/25 – Hurricane Melissa disappeared off the tracking charts yesterday. And when it did, one of the most powerful storms in recorded history went into the history books.
Many things made Melissa unusual and stunned meteorologists. They included the storm’s deep pressure, high winds, rapid intensification, death toll, destruction, and its timing within the hurricane season.
And all of that happened in a season that has, so far, spared the U.S. mainland from any landfalling hurricanes.
A Normal Season
Usually, the Atlantic Hurricane season is largely over by the end of October.
But this season was different.
This Season
Melissa was the 13th named storm of the season.
In May this year, NOAA predicted an above average season with 13-19 named storms, of which 6-10 would become hurricanes, including 3-5 major hurricanes.
So far, we’ve had 13 named storms. Five became hurricanes, four of which reached major hurricane strength. See below.
Why So Strong, So Late?
First, we had very warm waters in the Caribbean – 1.9ºC to 2.8ºC above average for the region and season. That’s up to 5º F warmer than average.
More importantly: the warm layer extended to depth — meaning the storm could churn up deeper water without encountering cooler up-welled water that normally weakens storms.
Second, reduced wind sheer and steering currents caused it to meander slowly. This helped it sit over very warm waters while enhancing its strength.
Melissa underwent two rounds of rapid intensification, including a gain of ~70 mph in 24 hours — an “extreme rapid intensification” event. Because water was abnormally warm for that late in the season, and other inhibiting factors were low, the conditions aligned for a major hurricane even though the calendar was later.
Sea surface temperatures ordinarily decline and atmospheric conditions become less favorable this late in the season. But not this year. So, Melissa could reach peak strength even in late October. Some scientists hypothesize that climate change may have played a role. Others believe it was just the random confluence of favorable factors.
Warm water is necessary but not sufficient to create a major hurricane. In this case, the atmosphere cooperated, which is part of why Melissa could intensify so late and so rapidly.
Typically by late October, conditions become less favorable for hurricane formation (cooler oceans, increasing shear, etc.).
One For the Record Books
One study estimated that the extra warming of the ocean helped boost Melissa’s maximum wind speed by about 10 mph and increased its damage potential by ~50%.
ABC News reported that at least two hurricane-hunter aircraft had to turn back from Hurricane Melissa due to extreme turbulence: one from the U.S. Air Force Reserve 53rd Weather Reconnaissance Squadron and another from NOAA.
Melissa made landfall in Jamaica with sustained winds of 185 mph, tying it for the strongest Atlantic hurricane landfall by wind speed. (Wikipedia+4AP News+4CBS News+4).
A scientist from the University of Miami onboard the Hurricane Hunter recorded a spot wind gust of 252 MPH. If verified, it will be the highest speed ever recorded in a tropical cyclone by a dropsonde. That rivals winds in EF5 tornadoes!
Melissa also recorded a central pressure of 892 mb, tying the record for third‐lowest minimum central pressure in the Atlantic basin. (CT Insider+1).
So far, Melissa is the strongest tropical cyclone of any kind worldwide in 2025.
USA Today reported today that the storm left more than 60 people dead in Haiti, Jamaica and the Dominican Republic.
Posted by Bob Rehak on 11/2/25
2987 Days since Harvey
Evolution of Harris County Flood-Project Prioritization
11/1/2025 – On 10/28/25, members of the Harris County Community Flood Resilience Task Force received a brief presentation about how flood-mitigation projects get prioritized by Harris County.
Below are several key slides from “Overview & History of the 2018 Bond Program’s Prioritization Framework.”
How Prioritization Started
Before the 2018 bond election on the anniversary of Hurricane Harvey, language was inserted into the proposal that voters went on to approve. Specifically, note Paragraph 14G. It called for developing a process for the “equitable expenditure of funds.”
Another year later, the county (under the guise of Harris Thrives) adopted two resolutions. The first instructed Harris County Flood Control District to adopt a framework for the equitable expenditure of Bond Program funds. The second set up a community-based Task Force.
“Harris Thrives” is the name of a resilience strategy adopted by Harris County after Harvey. It claims to be a “fast, fair, smart” approach to flood control, but also includes housing. Specifically it claims the county will be:
Admirable goals. But it appears that Harris Thrives’ website has not been updated since February 2023, despite a promise to update it quarterly at that time. Only history and the Freedom of Information Act will tell us whether the county achieved those goals.
How Prioritization Framework Evolved
The Framework has gone through several iterations over time as commissioners’ priorities have changed.
Commissioners later also agreed to follow up on projects that had already received partnership funds (not shown above).
Regaining Transparency
Under previous management, HCFCD updated the status of every project for every commissioners court meeting. And those updates were posted online.
But since a change in management and priorities in 2022, it has been hard to identify where projects, budgets, and construction stands. Bond updates became annual as projects slowed to a crawl.
The old, simple-but-effective text-based lists with GANTT charts have been replaced by a series of somewhat confusing dashboards that work occasionally and with mixed effectiveness in different browsers.
Clicking on the dots calls up information about the associated project. But gone are the old, intuitive Gantt charts that gave you timing, lifecycle, and status information at a glance.
Sigh. At least they’re trying. And in fairness, they are improving. The Microsoft PowerBI spending charts on the HCFCD Activity Page are a valuable addition, even though that information is updated quarterly.
Changing Priorities
Through the years, priorities changed. The presentation showed the current scoring matrix.
However, it did not show the scoring matrix in the original 2019 Prioritization Framework. See below.
Comparison shows that flood-risk reduction and partnership funding (combined weight of 35%) have been eliminated from consideration. In their place, population and housing density (aka project efficiency) have increased by a similar amount. That favors projects near the city center, but eliminates severity of flooding as a consideration, which is why the largest watershed in the county with the worst flooding has received only 2% of spending to date.
Eliminating partnership funding is a curious switch, too, especially since more than half of bond-project funding relies on matching partnership dollars.
For More Information
Those who would like more information can:
Posted by Bob Rehak on 11/1/25
2986 Days since Hurricane Harvey