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?
For decades, we have had wetland mitigation banks. If you want to fill in wetlands, you need to preserve wetlands somewhere else. But what about those vast swaths of ecologically less valuable forest that still play valuable roles in flood reduction? Developers routinely mow them down for new starter homes, apartment complexes, strip centers, RV parks and the like. Should there be mitigation for clearcutting, too?
Imagine how much more attractive, healthier, and flood-resilient communities could become if all developers:
Planted a young tree for every old tree they cut, or…
Donated trees to community groups, or…
Preserved floodplains on their perimeters with conservation easements, or…
Committed to replanting trees on their own developments as homes are built.
Here’s why that’s important and two ways it could work without turning into a huge cost burden for developers and without onerous regulation.
That erosion eventually reaches streams and can reduce their conveyance. In extreme cases, eroded sediment can even block streams and back floodwaters up into homes.
How Clearcutting Can Increase Flood Risk
Clearcutting on the other had accelerates runoff. As runoff gets to streams faster, it carries more exposed sediment. That sediment can reduce the conveyance of streams, partially block them, back floodwater up, and necessitate dredging programs which can take years and cost tens of millions of dollars.
Clearcutting makes more money for developers. But it also can also foist cleanup, repair, and mitigation costs off on neighbors and the public sector as we saw with Woodridge Village.
Notice the stark contrast in each photo below between the mature canopy of trees surrounding each newly clearcut development.
One of the primary draws of SE Texas is the gorgeous, lush forests. Yet high-density development is gradually destroying the very thing that attracts people. So should there be some sort of mitigation for clearcutting?
A Modest Proposal
Most companies make charitable donations of some sort. If you’re a developer, why not make them in a way that builds goodwill with neighbors, supports community values, makes everyone safer, and creates a tax deduction?
Contrast the systemic, mechanized deforestation above with the underfunded efforts of volunteer and charitable groups trying to plant trees and preserve forests. Perhaps the first group could help the second…and help themselves at the same time.
And the tax breaks from a conservation easement can easily turn difficult-to-develop floodplain land into revenue-producing land.
Let’s look at examples of each.
Trees for Kingwood
Mayor Pro Tem Dave Martin’s most recent newsletter contained a short article about a new group called “Trees For Kingwood.”
Martin says, “Over the last 5 decades, Kingwood has lost more than ten thousand trees due to disease, storms, and drought.”
And I would point out that that doesn’t even include new developments that practice clearcutting.
Mayor Pro Tem Martin (front row, center) joined leaders of seven Kingwood Community Associations that contributed funds to support the first planting event of Trees for Kingwood. “This is a good thing for the neighborhood and wonderful for the community,” said Martin.
Trees for Kingwood needs both volunteers and financial support to achieve its mission.
Volunteers to help plant and care for new trees.
Financial support to purchase trees.
Charitable contributions can be made to the KSA Parks Foundation for the Trees for Kingwood effort. For more information please visit treesforkingwood.org or email treesforkingwood@gmail.com.
Bayou Land Conservancy
Another worthy group is the Bayou Land Conservancy (BLC). Since 1996, BLC has preserved land along streams for flood control, clean water, and wildlife. BLC’s focus area includes the Lake Houston Watershed, which is 4,000 square miles. The group has preserved 14,000 acres and has identified another 100,000 worthy of protection. The tax benefits of a conservation easement can help developers profit from flood-prone land that would be difficult and expensive to safely develop.
To put 14,000 acres in perspective, that’s the size of Kingwood.
Bottom Line
By supporting such groups, developers can help restore and protect the forests that attract people to this region. They can also help mitigate their development practices and reduce costs by harnessing the power of volunteers.
Posted by Bob Rehak on 12/3/22
1922 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/2022/12/20221126-DJI_0426.jpg?fit=1200%2C799&ssl=17991200adminadmin2022-12-03 17:53:372022-12-03 18:04:00Mitigation for Clearcutting: Two Ways It Could Work Cost Effectively
The Harris County Flood Control District (HCFCD) has scheduled a community meeting to reveal the results of an engineering study of the Taylor Gully watershed and Woodridge Village, the aborted development that flooded Elm Grove and North Kingwood Forest twice in 2019. The virtual meeting will be on:
December 14, 2022
6:30 PM – 7:30 PM
Two Related Efforts
Because Woodridge Village sits at the headwaters of Taylor Gully, the volume of stormwater detention upstream and the amount of conveyance needed downstream are related. More of one could mean less of the other. HCFCD has been working to find the optimum solution, which should be discussed at the meeting.
Areas of Concern Identified by Community Members
Community members previously expressed concerns, including:
Straightening a Taylor Gully oxbow adjacent to Woodstream Forest where numerous homes flooded.
Replacing the old culvert-style bridge on Rustic Elms with an open-span bridge.
The Rustic Elms Bridge on Taylor Gully has a twin-culvert design with less conveyance than more open bridges like the one at West Lake Houston Parkway farther downstream in this image. Nearly every home behind this bridge on adjacent streets flooded in 2019.
Hundreds of homes adjacent to Woodridge Village and Taylor Gully flooded twice in 2019 after a developer clearcut approximately 270 acres before building required stormwater detention basins.
The developer then sold the troubled project to HCFCD in March 2021 after building 271 acre feet of stormwater detention capacity – an amount sufficient to meet Montgomery County’s pre-Atlas-14 standards, which were in effect at the time of permitting.
Taylor Gully One of Top Two Priorities in Kingwood Area
The Kingwood-Area Drainage Analysis from October 2020 recommended Taylor Gully as one of the top two priorities for Kingwood. However, HCFCD also recommended the Taylor Gully project be re-analyzed to determine how the use of Woodridge Village for detention could modify the recommended plan.
Since February 2022, Sprint Sand & Clay has removed an average of more than 1,700 cubic feet of dirt each week from Woodridge. That’s roughly one acre foot per week. An acre foot equals 1613.33 cubic yards of material.
So, HCFCD has increased detention capacity by almost 42 acre feet since signing the contract with Sprint. That means detention capacity has already increased by about 16 percent, not quite half of what it needs to meet new Atlas-14 requirements.
Stats from HCFCD show cubic feet of dirt removed from Woodridge Village by Sprint Sand & Clay each week since start of E&R contract.
Pictures Showing Woodridge Village Status
Here are some pictures that show the extent of excavation on November 26, 2022.
Looking NE along Harris/Montgomery county line (tree line on right).Close-up shot of active work area.Looking S toward Sherwood Trails Village
Excavation and removal contracts give HCFCD a head start on construction of stormwater detention basins. The final dimensions may not be known yet, but HCFCD can make adjustments as it finalizes construction plans.
We should learn more about those on December 14th. Block out the date for the Taylor Gully, Woodridge Village meeting.
Posted by Bob Rehak on 12/2/2022
1921 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/12/20221126-DJI_0406.jpg?fit=1200%2C799&ssl=17991200adminadmin2022-12-02 15:56:062022-12-02 20:26:17Taylor Gully-Woodridge Village Meeting Scheduled for Dec. 14
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.
Mitigation for Clearcutting: Two Ways It Could Work Cost Effectively
For decades, we have had wetland mitigation banks. If you want to fill in wetlands, you need to preserve wetlands somewhere else. But what about those vast swaths of ecologically less valuable forest that still play valuable roles in flood reduction? Developers routinely mow them down for new starter homes, apartment complexes, strip centers, RV parks and the like. Should there be mitigation for clearcutting, too?
Imagine how much more attractive, healthier, and flood-resilient communities could become if all developers:
Here’s why that’s important and two ways it could work without turning into a huge cost burden for developers and without onerous regulation.
Role of Trees in Flood Reduction
Trees do more than increase the value of homes. They also play many roles in flood reduction. For instance, they:
That erosion eventually reaches streams and can reduce their conveyance. In extreme cases, eroded sediment can even block streams and back floodwaters up into homes.
How Clearcutting Can Increase Flood Risk
Clearcutting on the other had accelerates runoff. As runoff gets to streams faster, it carries more exposed sediment. That sediment can reduce the conveyance of streams, partially block them, back floodwater up, and necessitate dredging programs which can take years and cost tens of millions of dollars.
Clearcutting makes more money for developers. But it also can also foist cleanup, repair, and mitigation costs off on neighbors and the public sector as we saw with Woodridge Village.
Notice the stark contrast in each photo below between the mature canopy of trees surrounding each newly clearcut development.
One of the primary draws of SE Texas is the gorgeous, lush forests. Yet high-density development is gradually destroying the very thing that attracts people. So should there be some sort of mitigation for clearcutting?
A Modest Proposal
Most companies make charitable donations of some sort. If you’re a developer, why not make them in a way that builds goodwill with neighbors, supports community values, makes everyone safer, and creates a tax deduction?
Contrast the systemic, mechanized deforestation above with the underfunded efforts of volunteer and charitable groups trying to plant trees and preserve forests. Perhaps the first group could help the second…and help themselves at the same time.
The lumber revenue from one mature loblolly pine could plant ten more.
And the tax breaks from a conservation easement can easily turn difficult-to-develop floodplain land into revenue-producing land.
Let’s look at examples of each.
Trees for Kingwood
Mayor Pro Tem Dave Martin’s most recent newsletter contained a short article about a new group called “Trees For Kingwood.”
Martin says, “Over the last 5 decades, Kingwood has lost more than ten thousand trees due to disease, storms, and drought.”
And I would point out that that doesn’t even include new developments that practice clearcutting.
Mayor Pro Tem Martin (front row, center) joined leaders of seven Kingwood Community Associations that contributed funds to support the first planting event of Trees for Kingwood. “This is a good thing for the neighborhood and wonderful for the community,” said Martin.
Trees for Kingwood needs both volunteers and financial support to achieve its mission.
Charitable contributions can be made to the KSA Parks Foundation for the Trees for Kingwood effort. For more information please visit treesforkingwood.org or email treesforkingwood@gmail.com.
Bayou Land Conservancy
Another worthy group is the Bayou Land Conservancy (BLC). Since 1996, BLC has preserved land along streams for flood control, clean water, and wildlife. BLC’s focus area includes the Lake Houston Watershed, which is 4,000 square miles. The group has preserved 14,000 acres and has identified another 100,000 worthy of protection. The tax benefits of a conservation easement can help developers profit from flood-prone land that would be difficult and expensive to safely develop.
To put 14,000 acres in perspective, that’s the size of Kingwood.
Bottom Line
By supporting such groups, developers can help restore and protect the forests that attract people to this region. They can also help mitigate their development practices and reduce costs by harnessing the power of volunteers.
Posted by Bob Rehak on 12/3/22
1922 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.
Taylor Gully-Woodridge Village Meeting Scheduled for Dec. 14
The Harris County Flood Control District (HCFCD) has scheduled a community meeting to reveal the results of an engineering study of the Taylor Gully watershed and Woodridge Village, the aborted development that flooded Elm Grove and North Kingwood Forest twice in 2019. The virtual meeting will be on:
Two Related Efforts
Because Woodridge Village sits at the headwaters of Taylor Gully, the volume of stormwater detention upstream and the amount of conveyance needed downstream are related. More of one could mean less of the other. HCFCD has been working to find the optimum solution, which should be discussed at the meeting.
Areas of Concern Identified by Community Members
Community members previously expressed concerns, including:
Hundreds of homes adjacent to Woodridge Village and Taylor Gully flooded twice in 2019 after a developer clearcut approximately 270 acres before building required stormwater detention basins.
The developer then sold the troubled project to HCFCD in March 2021 after building 271 acre feet of stormwater detention capacity – an amount sufficient to meet Montgomery County’s pre-Atlas-14 standards, which were in effect at the time of permitting.
Taylor Gully One of Top Two Priorities in Kingwood Area
The Kingwood-Area Drainage Analysis from October 2020 recommended Taylor Gully as one of the top two priorities for Kingwood. However, HCFCD also recommended the Taylor Gully project be re-analyzed to determine how the use of Woodridge Village for detention could modify the recommended plan.
Here is the scope of work for the engineering company that worked on the Taylor Gully-Woodridge Village project.
42 More Acre Feet Removed to Date from Woodridge Village
In March 2021, Harris County and the City of Houston purchased the Woodridge Village property. They then started an Excavation and Removal Contract with Sprint Sand and Clay in January 2022 that could ultimately double the volume of stormwater detention on Woodridge Village.
Since February 2022, Sprint Sand & Clay has removed an average of more than 1,700 cubic feet of dirt each week from Woodridge. That’s roughly one acre foot per week. An acre foot equals 1613.33 cubic yards of material.
So, HCFCD has increased detention capacity by almost 42 acre feet since signing the contract with Sprint. That means detention capacity has already increased by about 16 percent, not quite half of what it needs to meet new Atlas-14 requirements.
Pictures Showing Woodridge Village Status
Here are some pictures that show the extent of excavation on November 26, 2022.
Excavation and removal contracts give HCFCD a head start on construction of stormwater detention basins. The final dimensions may not be known yet, but HCFCD can make adjustments as it finalizes construction plans.
We should learn more about those on December 14th. Block out the date for the Taylor Gully, Woodridge Village meeting.
Posted by Bob Rehak on 12/2/2022
1921 Days since Hurricane Harvey