It’s a minor victory. And it may not actually change anything on the ground. But the City of Houston today sent a signal to developers, who now have to identify flood prone areas on their general plans.
The move should eliminate any doubt among bankers, buyers and real estate agents as to whether a particular property is in a floodway or flood plain.
By following all the other guidelines, developers can still get their plans approved. This change helps people seeking truth and full disclosure in the sales process.
There’s one other key change. Another new requirement is that, as each section of a general plan is platted, it has to adhere to the then current standards. That is important so that the entire development isn’t grandfathered by the approval date of the general plan.
These changes may make some developers think twice about buying and developing flood-prone property. Especially if they target unknowledgeable buyers, such as young people or foreigners, who may be unfamiliar with American flood standards.
Today’s press release by the City of Houston’s Planning and Development department says the changes will go into effect July 24, 2020.
The release is being blasted out to developers also. It’s titled “Platting Updates for Flood Prone Areas.” I have reprinted the full text verbatim below.
IDENTIFICATION OF FLOOD PRONE AREAS ON GENERAL PLAN
Effective July 24, 2020
Flooding events have been increasingly severe in the City of Houston and our region. The 2018 amendment to Chapter 19 City of Houston Code of Ordinances mandated that it was necessary to evaluate development within the 100-year and 500-year floodplains to protect investments made by residents and business owners in real property within the City. Harris County and others have developed their own needs in improving the drainage in their regions.
To mitigate and reduce the risk of flood loss for future development, the 100-year, 500-year floodplains and floodway will be required to be identified on all General Plans submitted to the Department with the Plat Tracker application. Applicants will be required to graphically depict the location of the floodplains and or floodway on their General Plans and provide related note.
This information must be provided as part of initial submittal of a General Plan for Planning Commission consideration. The General Plan application will be marked incomplete if this information is not included as part of the initial submittal.
HOW TO ILLUSTRATE
The way to depict this information correctly is to go to the FEMA website through the following link: https://msc.fema.gov/portal/search#searchresultsanchor.Enter the address, place, or coordinates. The site will produce a map that will identify whether the property is located in the 100-year, 500-year flood plains or floodway. Provide a dashed line on your General Plan identifying the 100-year, 500-year flood plains or floodway as depicted on the FEMA map.
GENERAL PLAN RELATED NOTE
Also, include on the face of the General Plan the following related note as follows: Portions of the property included in this General Plan lie within the known floodway and the 100 and 500-year floodplains. As each section or parcel is platted and developed, the then-current standards of City of Houston [or if ETJ: Harris County] drainage, elevation, and building regulations must be adhered to.
For additional information contact Dipti Mathur at 832-393-6560.
Imagine how the general plan of “Orchard Seeded Ranches” would look. It would clearly show that virtually every property was subject to severe flooding. Also imagine now how those new townhomes in Kings Harbor will look to Chinese investors.
Developers who specialize these types of distress properties may have to rethink their marketing strategies.
Posted by Bob Rehak on 7/17/2020
1053 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/07/Screen-Shot-2020-07-17-at-4.56.38-PM.png?fit=810%2C404&ssl=1404810adminadmin2020-07-17 17:12:202020-07-18 06:48:48City of Houston Will Now Require Developers to Identify Flood-Prone Areas on Their General Plans
Note: the post below was condensed and adapted from a longer USGS article. The U.S. Geological Survey (USGS) records continuous stream stage (height of a river) and streamflow (how much water is flowing) with thousands of gages throughout the nation. But how can they determine flood height where no gages exist?
Simple, USGS correlates high water marks after floods with peak gage heights during floods.
“If, for example, records show that stream stage reached 17 feet during a storm, a high-water mark will show the hydrologist what a stage of 17 feet means in terms of how high the water was on the riverbanks and surrounding land.”
Finding high water marks on or near buildings is easy. You look for the mud line or the edge of debris fields. The same principle applies in nature. Sometimes it’s easy.
Think of high water marks like a bathtub ring around a flooded area. Shown here: East End Park after Imelda.
But they’re not always that obvious.
Can You Spot High Water Marks In Pictures Below?
Below are two pictures used by USGS for demonstration purposes. They took the pictures a few days after a record storm. High-water marks show in both pictures, although a hydrologist would only regard one of the marks as being reliable.
Spot the high water marks.
The pictures below are close-ups of the high-water indicators in the top pictures. Did you spot them?
The left picture shows a poison ivy vine with the bottom leaves covered in dried mud. Where the mud stops shows how high the floodwaters reached.
The right-side picture shows a limb that hangs over the same creek. During a flood, rapidly-moving water carries leaves and pine needles, etc.! They stick on limbs that are partially submerged. When the stream recedes the signs remain. The top of the leaves and pine straw indicate how high the creek was during the storm.
The mud on the vine is a much better high-water mark than the tree limb, though. During high water, the fast-moving water will cause partially submerged limbs to move up and down. Therefore, hydrologists would not use the limb to estimate high water.
How High Water Marks Are Used
Planning Development
Documenting high water marks helps plan development near floodplains. If you know that water reaches a certain mark on the bank every few years, you certainly don’t want people building homes and businesses there.
Determining Extent and Severity of Flooding
Gages can determine the height of a flood. But high water marks can also show the width and extent relative to topography.
After most major flood events, USGS partners with FEMA and other state and federal agencies to flag and survey high water marks in areas that flooded. USGS did so here after Harvey to determine the extent and severity of the flooding.
Prediction of Future Floods
Forecasters can use the data associated with high-water marks to predict the severity of future floods, delineate flood zones, and update current maps that may account for changes in upstream conditions.
Flood Frequency Calculations
High-water mark data is also part of the flood-frequency (or recurrence interval) calculations that FEMA uses to identify areas that are likely to experience a 1 percent chance of happening in any given year. These floods, known as 100-year floods, serve as the foundation for flood management planning.
Inundation Mapping
Another significant use: Flood-Inundation Mapping. A flood-inundation map shows the extent and depth of flooding that occurred in various communities as a result of a major storm or flood event. Inundation maps help determine things like:
Changes needed in building codes
Evacuation routes
Heights of bridges and roads.
Once inundation maps are complete, USGS documents them and makes them publicly available online.
Recreating Data from Damaged Gages
If a flood knocks out a gage, as it did with the one at US59 bridge and the Kingwood Country Club on the San Jacinto West Fork, high-water marks can provide maximum height of a flood after the fact. If the cross section of the river is known (or surveyed), hydrologists can even back-calculate the flow rate.
Posted by Bob Rehak on 7/16/2020 with thanks to USGS and Diane Cooper
1052 Days after Hurricane Harvey and 301 since Imelda
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/07/20170915-San-JacintoRJR_3366_308.jpg?fit=1200%2C800&ssl=18001200adminadmin2020-07-16 19:57:082020-07-16 20:23:08How High Water Marks Help Fill Gaps in Flood Knowledge
Almost 40 years ago, when I moved to Houston, I fell in love with the extraordinary beauty of this City. And nowhere in Houston is more beautiful than the Lake Houston Area. The pictures below show why it’s worth fighting for.
Nature in the Lake Houston Area isn’t a place you go to visit. You don’t have to drive or fly to it. It’s all around you. Step out your back door and you’re already there. You’re breathing it. You’re being it.
Harvey Was an Eye Opener
Right up until Hurricane Harvey, I felt, on balance, this was the most perfect place in America to raise my family. Houston offers career opportunities found in few other cities. And the Lake Houston Area, in particular, offers the things my family and I value.
Harvey didn’t change my mind about those things. But it did open my eyes to some things I should have paid closer attention to. All around us, that perfect environment was quietly and steadily being eroded for decades.
It’s not gone. But it is threatened. Every day. More than a thousand other posts on this web site amply chronicle those threats. I won’t dwell on them here. Nor will I dwell on how “the greatest flood ever” kept being replaced by the new “greatest flood ever.”
What We Need to Fight For
I would like, instead, to share several images that show it’s not too late to preserve what we have. But to do that, we have to fight for it.
We need to fight for:
Responsible aggregate mining.
Better development practices that respect nature.
Upstream floodplain regulations that reduce flooding.
Flood mitigation efforts that keep the 100-year floodplain a 100-year floodplain.
Why We Need to Fight
I took all of the pictures below in the last three months. They show what we need to save. All were shot inside America’s fourth largest city, which makes them even more unique.
The Kingwood Country Club’s Lake Course.Can you spot the thousands of homes around it?West Fork of the San Jacinto with Lake Houston on the horizon. Looking SE.For decades, development preserved nature.This is the result.Looking north at Lake Houston across the spillway.Looking south over the Lake Houston Dam toward the industry that powers America and the world.Looking east from the West Fork toward the East Fork of the San Jacinto with Royal Shores between them.Looking north along the East Fork. Kingwood’s East End Park is in the center and Huffman is on the right.Looking SE. FM1960 cuts across Lake Houston and through Huffman in the foreground Looking Southwest in the opposite direction from over FM1960, with Lake Houston in background.Looking East across FM2100 and Huffman toward Kingwood on the other side of the lake.Looking West. The Luce Bayou Interbasin Transfer Project where it enters into Luce Bayou and the headwaters of Lake Houston.Looking north from the Commons on Lake Houston toward where the new Grand Parkway is circling Houston (out of sight) near the top of the frame.This entire area could soon be developed.Looking southeast across Kingwood Park High School. Kingwood, where 70,000 people live, is almost invisible, hidden among the trees between the school and Lake Houston at the top of the frame.Looking north over Forest Cove, toward I-69 and Insperity, Kingwood’s $4 billion company, all hidden in the trees.Looking NW from the confluence of Spring Creek and the San Jacinto West Fork.All of this land has been bought by a developer.Fishing from your back door.
If this isn’t worth fighting for, I don’t know what is.
Bob Rehak
Please join the fight. There’s another legislative session starting in six months.
Posted by Bob Rehak on 7/15/2020
1051 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/07/20200616-RJR_3539.jpg?fit=1200%2C800&ssl=18001200adminadmin2020-07-15 21:33:202020-07-15 23:00:01Worth Fighting For
City of Houston Will Now Require Developers to Identify Flood-Prone Areas on Their General Plans
It’s a minor victory. And it may not actually change anything on the ground. But the City of Houston today sent a signal to developers, who now have to identify flood prone areas on their general plans.
By following all the other guidelines, developers can still get their plans approved. This change helps people seeking truth and full disclosure in the sales process.
There’s one other key change. Another new requirement is that, as each section of a general plan is platted, it has to adhere to the then current standards. That is important so that the entire development isn’t grandfathered by the approval date of the general plan.
These changes may make some developers think twice about buying and developing flood-prone property. Especially if they target unknowledgeable buyers, such as young people or foreigners, who may be unfamiliar with American flood standards.
Today’s press release by the City of Houston’s Planning and Development department says the changes will go into effect July 24, 2020.
The release is being blasted out to developers also. It’s titled “Platting Updates for Flood Prone Areas.” I have reprinted the full text verbatim below.
IDENTIFICATION OF FLOOD PRONE AREAS ON GENERAL PLAN
Effective July 24, 2020
Flooding events have been increasingly severe in the City of Houston and our region. The 2018 amendment to Chapter 19 City of Houston Code of Ordinances mandated that it was necessary to evaluate development within the 100-year and 500-year floodplains to protect investments made by residents and business owners in real property within the City. Harris County and others have developed their own needs in improving the drainage in their regions.
To mitigate and reduce the risk of flood loss for future development, the 100-year, 500-year floodplains and floodway will be required to be identified on all General Plans submitted to the Department with the Plat Tracker application. Applicants will be required to graphically depict the location of the floodplains and or floodway on their General Plans and provide related note.
This information must be provided as part of initial submittal of a General Plan for Planning Commission consideration. The General Plan application will be marked incomplete if this information is not included as part of the initial submittal.
HOW TO ILLUSTRATE
The way to depict this information correctly is to go to the FEMA website through the following link: https://msc.fema.gov/portal/search#searchresultsanchor.Enter the address, place, or coordinates. The site will produce a map that will identify whether the property is located in the 100-year, 500-year flood plains or floodway. Provide a dashed line on your General Plan identifying the 100-year, 500-year flood plains or floodway as depicted on the FEMA map.
GENERAL PLAN RELATED NOTE
Also, include on the face of the General Plan the following related note as follows: Portions of the property included in this General Plan lie within the known floodway and the 100 and 500-year floodplains. As each section or parcel is platted and developed, the then-current standards of City of Houston [or if ETJ: Harris County] drainage, elevation, and building regulations must be adhered to.
DISTRIBUTION
This document is being circulated to our customer eblast and posted on our Development Services web page https://www.houstontx.gov/planning/DevelopRegs/..
For additional information contact Dipti Mathur at 832-393-6560.
Imagine how the general plan of “Orchard Seeded Ranches” would look. It would clearly show that virtually every property was subject to severe flooding. Also imagine now how those new townhomes in Kings Harbor will look to Chinese investors.
Developers who specialize these types of distress properties may have to rethink their marketing strategies.
Posted by Bob Rehak on 7/17/2020
1053 Days since Hurricane Harvey
How High Water Marks Help Fill Gaps in Flood Knowledge
Note: the post below was condensed and adapted from a longer USGS article. The U.S. Geological Survey (USGS) records continuous stream stage (height of a river) and streamflow (how much water is flowing) with thousands of gages throughout the nation. But how can they determine flood height where no gages exist?
Simple, USGS correlates high water marks after floods with peak gage heights during floods.
Finding high water marks on or near buildings is easy. You look for the mud line or the edge of debris fields. The same principle applies in nature. Sometimes it’s easy.
But they’re not always that obvious.
Can You Spot High Water Marks In Pictures Below?
Below are two pictures used by USGS for demonstration purposes. They took the pictures a few days after a record storm. High-water marks show in both pictures, although a hydrologist would only regard one of the marks as being reliable.
The pictures below are close-ups of the high-water indicators in the top pictures. Did you spot them?
The left picture shows a poison ivy vine with the bottom leaves covered in dried mud. Where the mud stops shows how high the floodwaters reached.
The right-side picture shows a limb that hangs over the same creek. During a flood, rapidly-moving water carries leaves and pine needles, etc.! They stick on limbs that are partially submerged. When the stream recedes the signs remain. The top of the leaves and pine straw indicate how high the creek was during the storm.
The mud on the vine is a much better high-water mark than the tree limb, though. During high water, the fast-moving water will cause partially submerged limbs to move up and down. Therefore, hydrologists would not use the limb to estimate high water.
How High Water Marks Are Used
Planning Development
Documenting high water marks helps plan development near floodplains. If you know that water reaches a certain mark on the bank every few years, you certainly don’t want people building homes and businesses there.
Determining Extent and Severity of Flooding
Gages can determine the height of a flood. But high water marks can also show the width and extent relative to topography.
After most major flood events, USGS partners with FEMA and other state and federal agencies to flag and survey high water marks in areas that flooded. USGS did so here after Harvey to determine the extent and severity of the flooding.
Prediction of Future Floods
Forecasters can use the data associated with high-water marks to predict the severity of future floods, delineate flood zones, and update current maps that may account for changes in upstream conditions.
Flood Frequency Calculations
High-water mark data is also part of the flood-frequency (or recurrence interval) calculations that FEMA uses to identify areas that are likely to experience a 1 percent chance of happening in any given year. These floods, known as 100-year floods, serve as the foundation for flood management planning.
Inundation Mapping
Another significant use: Flood-Inundation Mapping. A flood-inundation map shows the extent and depth of flooding that occurred in various communities as a result of a major storm or flood event. Inundation maps help determine things like:
Once inundation maps are complete, USGS documents them and makes them publicly available online.
Recreating Data from Damaged Gages
If a flood knocks out a gage, as it did with the one at US59 bridge and the Kingwood Country Club on the San Jacinto West Fork, high-water marks can provide maximum height of a flood after the fact. If the cross section of the river is known (or surveyed), hydrologists can even back-calculate the flow rate.
Posted by Bob Rehak on 7/16/2020 with thanks to USGS and Diane Cooper
1052 Days after Hurricane Harvey and 301 since Imelda
Worth Fighting For
Almost 40 years ago, when I moved to Houston, I fell in love with the extraordinary beauty of this City. And nowhere in Houston is more beautiful than the Lake Houston Area. The pictures below show why it’s worth fighting for.
Nature in the Lake Houston Area isn’t a place you go to visit. You don’t have to drive or fly to it. It’s all around you. Step out your back door and you’re already there. You’re breathing it. You’re being it.
Harvey Was an Eye Opener
Right up until Hurricane Harvey, I felt, on balance, this was the most perfect place in America to raise my family. Houston offers career opportunities found in few other cities. And the Lake Houston Area, in particular, offers the things my family and I value.
Harvey didn’t change my mind about those things. But it did open my eyes to some things I should have paid closer attention to. All around us, that perfect environment was quietly and steadily being eroded for decades.
It’s not gone. But it is threatened. Every day. More than a thousand other posts on this web site amply chronicle those threats. I won’t dwell on them here. Nor will I dwell on how “the greatest flood ever” kept being replaced by the new “greatest flood ever.”
What We Need to Fight For
I would like, instead, to share several images that show it’s not too late to preserve what we have. But to do that, we have to fight for it.
We need to fight for:
Why We Need to Fight
I took all of the pictures below in the last three months. They show what we need to save. All were shot inside America’s fourth largest city, which makes them even more unique.
Please join the fight. There’s another legislative session starting in six months.
Posted by Bob Rehak on 7/15/2020
1051 Days since Hurricane Harvey