The developer of a proposed new high-rise resort in Kingwood plans to develop the marina portion in an area that was once the riverbed of the San Jacinto west fork.
Aerial photos taken in 1943 clearly show the outline of an old meander about .4 miles north of the current riverbed.
1943 aerial photo. Note feint outline of old riverbed above the current river.
Google Earth lets users trace a path and then save it, like I have with this orange line.
Creating an outline of the path allows you to scroll forward in time within Google Earth (see image below).
Here is the same path superimposed over current conditions.
Plans call for marina high rises along orange path just north of lake below eastern edge of Barrington.The Marina would be developed in the old river bed of the San Jacinto.
Photo of proposed marina site next to River Grove Park. The giant sand bar in the foreground of this photo taken after Harvey has mostly been dredged by the Army Corps. However, it’s appearance almost overnight during Harvey contributed to the flooding of 650 homes above the drainage ditch (center left). Future development in this floodplain would likely make flooding worse.
Dangers of Building in Old Stream and Riverbeds
During major floods, water often follows these old streams and riverbeds. Many neighborhoods in Houston discovered this danger during Harvey. Former Harris County Judge Ed Emmett often questioned the wisdom of such developments because of their susceptibility to flooding – even after mitigation.
Here are two examples that show such developments encroaching on waterways and separating them from their floodplains. In the first example, the waterway was obliterated. In the second, White Oak Bayou, the waterway still exists. However, the flood plain has been developed. Despite mitigation efforts during development, the neighborhoods around White Oak Bayou have suffered severe and repeated flooding.
Why Do We Continue to Develop Flood Plains?
This brochure, Why We Continue to Develop Floodplains: Examining the Disincentives for Conservation in Federal Policy, is a must-read for anyone who wants to understand the financial logic behind developments like this one. A group called Earth Economics developed it. Zachary Christin, Project Director for Earth Economics, and Michael Kline, from the Vermont Department of Environmental Conservation, authored it with support from the Kresge Foundation. This report investigates whether current federal policy is structured to prevent future flood damage or if incentives lead to further floodplain development.
The basic premise may rub many Texans the wrong way, but you should still read it. “Flood risk management,” the authors argue, “seeks to enable communities to live nearby by controlling rivers with levee systems and other structures. This false sense of protection places families and infrastructure at risk in a climate that is changing beyond our capacity to maintain protections against its effects. Rather than attempting to control our country’s powerful rivers, we should instead control how and where we allow human activities.”
Confining streams, they argue, merely shifts flood risk downstream. The authors explore the benefits and the natural protective qualities of healthy, functional floodplains. They then discuss the causes of floodplain destruction and investigate the policies that further incentivize their development. Finally, they outline paths forward to create new floodplain policy. You may disagree with the premise. But it contains many powerful observations and statistics.
As always, these represent my opinions on matters of public policy. They are protected by the First Amendment of the U.S. Constitution and the Anti-SLAPP statute of the Great State of Texas.
Posted by Bob Rehak on January 2, 2019
491 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/01/AncientMeander.jpg?fit=1500%2C1023&ssl=110231500adminadmin2019-01-02 19:38:332019-01-13 12:36:05Developer Plans to Build High-Rise Resort in Old Riverbed
Flash flooding and flooding will be possible Wednesday into Thursday. A band of heavy rainfall may form Wednesday morning from College Station to Crockett and heavy rainfall may continue to occur through the day. Gulf moisture will also move into the area and cause additional rainfall mainly east of I-45.
Southeast Texas has already had rainfall the last seven days which will cause any additional rainfall to runoff. Isolated thunderstorms may cause brief heavy rainfall of 1 inch an hour. Overall areas in the watch may get 2 to 3 inches of rainfall with isolated bands of 4 inches.
Potential Flood Impacts
In urban areas, street flooding and flooding of underpasses and typical low lying areas can be be expected. Bayous and creeks may have rapid rises and could reach out of banks. Rural low lying areas, low water crossings and poor drainage areas may flood. Rises on area rivers can be expected and this could extend river flooding that is on going.
PRECAUTIONARY/PREPAREDNESS ACTIONS
A Flash Flood Watch means that conditions may develop that lead to flash flooding. Flash flooding is a very dangerous situation. You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued.
Additional Guidance from Harris County Flood Control
Jeff Lindner, Harris County Flood Control’s meteorologist added this:
Widespread rainfall…some heavy…will lead to rises on area watersheds and potentially some flooding of creeks and rivers.
Upper level storm system is digging into the SW US and will impact the state for the next 24-36 hours.
As moisture increases from the SSW this evening, light rain and showers will develop and spread NNE into the area. A secondary front from roughly Lake Livingston to Columbus will likely remain stationary and be the focus for rainfall production tonight into early Wednesday in that region. Expect numerous showers and thunderstorms to develop by midday along the coast and inland south of the stalled inland front…this rainfall will likely become heavier in nature and slightly more convective with potentially higher rainfall rates. Upper level system will move across the area early Thursday with rains continuing before dry WNW winds sweep across the area in the afternoon ending rainfall.
Rainfall Amounts
Widespread rainfall of 2-3 inches looks likely over much of the area with isolated totals of 4-5 inches. Some fairly decent agreement in the models today with respect to two rainfall maximums over the area…the first over our NW/N counties tonight in Wednesday and then a second Wednesday afternoon into Thursday morning from Houston ENE toward Liberty and then NE toward Lake Livingston. WPC has expended the slight risk of excessive rainfall exceeding flash flood guidance to include a larger part of SE TX. Think maximum hourly rainfall rates will be on the order of .5 to 1.25 inches which most urban areas will be able to handle. Overall fairly long duration of rainfall over a fairly large area will lead to significant amounts of run-off especially into area river systems as well as the creeks in northern Harris County.
Flash Flood Guidance
Flash Flood Guidance for the area is between 3.0-4.4 inches for 6-hrs which seems high and a review of soil saturation levels via the NASA SPORT webpage shows saturation levels of 65-70% over much of the area…or you can walk in the yard and quickly tell that the ground is still very wet from the rainfall on Sunday. Think much of what falls is going to run-off given how wet the ground is and widespread amounts of dormant vegetation.
Several watersheds are still high from the rainfall last Thursday and rainfall of this magnitude will likely result in renewed rises on nearly all watersheds. Main concern will be the Trinity and San Jacinto basins, along with the Navasota and Brazos. In Harris County, significant rises on Spring, Cypress, Little Cypress, Willow, Cedar, and the creeks that feed into Addicks and Barker Reservoirs are likely. Will also include lower Greens (east of US 59) and Halls, Hunting. Some of these watersheds may rise to levels that would impact low lying areas and roadways near the creek or bayou.
Flooding Probable on East and West Forks
Flooding on both the East and West Forks of the San Jacinto River (low lands and streets) certainly looks probable. At this time the threat for significant creek and bayou flooding as well as any flooding of structures is low.
Current thinking is that watersheds will see similar responses to last Thursday morning…although a few may see higher levels since they will be starting at higher current flows versus last Thursday.
Think hourly rainfall rates will be low enough to prevent widespread street flooding, but street flooding in areas of poor drainage and in rural areas where roadside ditches or small creeks spill onto the roadway will be possible.
Posted by Bob Rehak on 1/1/2019
480 Days Since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/01/Balcom_25.jpg?fit=1500%2C1000&ssl=110001500adminadmin2019-01-01 18:30:232019-01-01 18:30:29Flash Flood Watch Issued from 6 a.m. Wednesday to Noon Thursday
Yesterday, the area where a developer proposes a new high-rise development flooded for the fifth time this year. This underscores the need for remediation before any permitting.
It wasn’t an especially heavy rain last week. Kingwood received about 2.5 inches. Areas upstream averaged 3 to 4 inches. Yet the West Fork came out of its banks and flooded River Grove Park for the fifth time this year (February 26, March 28/29, July 4, December 7/8, December 27). The USGS Gage at US59 showed that the flood crested at about midnight. The crest reached almost 50 feet at US59.
The West Fork at US 59 crested at almost 50 feet from the most recent rains. In the days preceding, SJRA released 5-7,000 cfs from Lake Conroe.
Jim Zura of Zura Productions took his drone to River Grove during the last light before the overnight crest. The video shows that although the road was still useable, many of the park’s popular amenities were not. The playground, soccer fields, boat ramp and boardwalk all flooded.
Earlier this year, the US Army Corps of Engineers found that excessive sedimentation in the river contributed to excessive flooding. The frequency of these floods supports that conclusion. The Corps began dredging in late September to remove sediment, but has completed only about 20% of the project so far. Downstream blockages remain. And the biggest – at the mouth of the West Fork – is not even within the scope of the current dredging project.
The end of Zura’s video shows the soccer fields and adjoining property, including a small lake in the floodway. This flood gives us a glimpse of how a minor rain would affect the proposed high-rise development there.
Watch all the way to the end!
The frequency of these floods underscores the need to consider the implications of permitting such a major development – especially when officials know the engineering is based on obsolete data and flood maps that in no way reflect current realities.
Until remediation efforts are complete, officials should postpone consideration of the permit. Remediation efforts include:
Dredging the West Fork all the way from US59 to Lake Houston
Creating additional upstream detention
Adding flood gates to Lake Houston
Restoring the conveyance of local drainage ditches and streams.
Rainfalls of the magnitude that caused these five floods should happen about once every 2 years according to Harris County Flood Control. This year they happened five times: 10X greater than expected. A review of peak crest data since 1929 roughly confirms these expectations. In the 80 year since then, the river crested over 50 feet only 40 times.
A review of the same data shows that the river has crested over 57 feet 9 times in the last 80 years and six times since 1994.
I believe excessive sedimentation played a role in this frequency increase. Instead of flooding every other year like this, we’re flooding almost every other month. That’s significant enough to put the brakes on development in the floodway, at least until we understand the extent of the problems and can fix them.
These are my opinions on matters of public policy. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statutes of the Great State of Texas.
Posted by Bob Rehak on December 31, 2018
489 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2018/12/Zura2.jpg?fit=1500%2C843&ssl=18431500adminadmin2018-12-30 13:08:172019-01-26 08:03:54Drone Video Underscores Dangers of Development without Remediation
Developer Plans to Build High-Rise Resort in Old Riverbed
The developer of a proposed new high-rise resort in Kingwood plans to develop the marina portion in an area that was once the riverbed of the San Jacinto west fork.
Aerial photos taken in 1943 clearly show the outline of an old meander about .4 miles north of the current riverbed.
Google Earth lets users trace a path and then save it, like I have with this orange line.
Here is the same path superimposed over current conditions.
Dangers of Building in Old Stream and Riverbeds
During major floods, water often follows these old streams and riverbeds. Many neighborhoods in Houston discovered this danger during Harvey. Former Harris County Judge Ed Emmett often questioned the wisdom of such developments because of their susceptibility to flooding – even after mitigation.
Here are two examples that show such developments encroaching on waterways and separating them from their floodplains. In the first example, the waterway was obliterated. In the second, White Oak Bayou, the waterway still exists. However, the flood plain has been developed. Despite mitigation efforts during development, the neighborhoods around White Oak Bayou have suffered severe and repeated flooding.
Why Do We Continue to Develop Flood Plains?
This brochure, Why We Continue to Develop Floodplains: Examining the Disincentives for Conservation in Federal Policy, is a must-read for anyone who wants to understand the financial logic behind developments like this one. A group called Earth Economics developed it. Zachary Christin, Project Director for Earth Economics, and Michael Kline, from the Vermont Department of Environmental Conservation, authored it with support from the Kresge Foundation. This report investigates whether current federal policy is structured to prevent future flood damage or if incentives lead to further floodplain development.
The basic premise may rub many Texans the wrong way, but you should still read it. “Flood risk management,” the authors argue, “seeks to enable communities to live nearby by controlling rivers with levee systems and other structures. This false sense of protection places families and infrastructure at risk in a climate that is changing beyond our capacity to maintain protections against its effects. Rather than attempting to control our country’s powerful rivers, we should instead control how and where we allow human activities.”
Confining streams, they argue, merely shifts flood risk downstream. The authors explore the benefits and the natural protective qualities of healthy, functional floodplains. They then discuss the causes of floodplain destruction and investigate the policies that further incentivize their development. Finally, they outline paths forward to create new floodplain policy. You may disagree with the premise. But it contains many powerful observations and statistics.
As always, these represent my opinions on matters of public policy. They are protected by the First Amendment of the U.S. Constitution and the Anti-SLAPP statute of the Great State of Texas.
Posted by Bob Rehak on January 2, 2019
491 Days since Hurricane Harvey
Flash Flood Watch Issued from 6 a.m. Wednesday to Noon Thursday
The National Weather Service in Houston/Galveston has issued a Flash Flood Watch for a large portion of southeast Texas…including Harris, Madison, Montgomery, Liberty, San Jacinto, Walker, Waller and Washington Counties. From Wednesday morning through Thursday morning.
Flash flooding and flooding will be possible Wednesday into Thursday. A band of heavy rainfall may form Wednesday morning from College Station to Crockett and heavy rainfall may continue to occur through the day. Gulf moisture will also move into the area and cause additional rainfall mainly east of I-45.
Southeast Texas has already had rainfall the last seven days which will cause any additional rainfall to runoff. Isolated thunderstorms may cause brief heavy rainfall of 1 inch an hour. Overall areas in the watch may get 2 to 3 inches of rainfall with isolated bands of 4 inches.
Potential Flood Impacts
In urban areas, street flooding and flooding of underpasses and typical low lying areas can be be expected. Bayous and creeks may have rapid rises and could reach out of banks. Rural low lying areas, low water crossings and poor drainage areas may flood. Rises on area rivers can be expected and this could extend river flooding that is on going.
PRECAUTIONARY/PREPAREDNESS ACTIONS
A Flash Flood Watch means that conditions may develop that lead to flash flooding. Flash flooding is a very dangerous situation. You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued.
Additional Guidance from Harris County Flood Control
Jeff Lindner, Harris County Flood Control’s meteorologist added this:
Widespread rainfall…some heavy…will lead to rises on area watersheds and potentially some flooding of creeks and rivers.
Upper level storm system is digging into the SW US and will impact the state for the next 24-36 hours.
As moisture increases from the SSW this evening, light rain and showers will develop and spread NNE into the area. A secondary front from roughly Lake Livingston to Columbus will likely remain stationary and be the focus for rainfall production tonight into early Wednesday in that region. Expect numerous showers and thunderstorms to develop by midday along the coast and inland south of the stalled inland front…this rainfall will likely become heavier in nature and slightly more convective with potentially higher rainfall rates. Upper level system will move across the area early Thursday with rains continuing before dry WNW winds sweep across the area in the afternoon ending rainfall.
Rainfall Amounts
Widespread rainfall of 2-3 inches looks likely over much of the area with isolated totals of 4-5 inches. Some fairly decent agreement in the models today with respect to two rainfall maximums over the area…the first over our NW/N counties tonight in Wednesday and then a second Wednesday afternoon into Thursday morning from Houston ENE toward Liberty and then NE toward Lake Livingston. WPC has expended the slight risk of excessive rainfall exceeding flash flood guidance to include a larger part of SE TX. Think maximum hourly rainfall rates will be on the order of .5 to 1.25 inches which most urban areas will be able to handle. Overall fairly long duration of rainfall over a fairly large area will lead to significant amounts of run-off especially into area river systems as well as the creeks in northern Harris County.
Flash Flood Guidance
Flash Flood Guidance for the area is between 3.0-4.4 inches for 6-hrs which seems high and a review of soil saturation levels via the NASA SPORT webpage shows saturation levels of 65-70% over much of the area…or you can walk in the yard and quickly tell that the ground is still very wet from the rainfall on Sunday. Think much of what falls is going to run-off given how wet the ground is and widespread amounts of dormant vegetation.
Several watersheds are still high from the rainfall last Thursday and rainfall of this magnitude will likely result in renewed rises on nearly all watersheds. Main concern will be the Trinity and San Jacinto basins, along with the Navasota and Brazos. In Harris County, significant rises on Spring, Cypress, Little Cypress, Willow, Cedar, and the creeks that feed into Addicks and Barker Reservoirs are likely. Will also include lower Greens (east of US 59) and Halls, Hunting. Some of these watersheds may rise to levels that would impact low lying areas and roadways near the creek or bayou.
Flooding Probable on East and West Forks
Flooding on both the East and West Forks of the San Jacinto River (low lands and streets) certainly looks probable. At this time the threat for significant creek and bayou flooding as well as any flooding of structures is low.
Current thinking is that watersheds will see similar responses to last Thursday morning…although a few may see higher levels since they will be starting at higher current flows versus last Thursday.
Think hourly rainfall rates will be low enough to prevent widespread street flooding, but street flooding in areas of poor drainage and in rural areas where roadside ditches or small creeks spill onto the roadway will be possible.
Posted by Bob Rehak on 1/1/2019
480 Days Since Hurricane Harvey
Drone Video Underscores Dangers of Development without Remediation
Yesterday, the area where a developer proposes a new high-rise development flooded for the fifth time this year. This underscores the need for remediation before any permitting.
It wasn’t an especially heavy rain last week. Kingwood received about 2.5 inches. Areas upstream averaged 3 to 4 inches. Yet the West Fork came out of its banks and flooded River Grove Park for the fifth time this year (February 26, March 28/29, July 4, December 7/8, December 27). The USGS Gage at US59 showed that the flood crested at about midnight. The crest reached almost 50 feet at US59.
Jim Zura of Zura Productions took his drone to River Grove during the last light before the overnight crest. The video shows that although the road was still useable, many of the park’s popular amenities were not. The playground, soccer fields, boat ramp and boardwalk all flooded.
Earlier this year, the US Army Corps of Engineers found that excessive sedimentation in the river contributed to excessive flooding. The frequency of these floods supports that conclusion. The Corps began dredging in late September to remove sediment, but has completed only about 20% of the project so far. Downstream blockages remain. And the biggest – at the mouth of the West Fork – is not even within the scope of the current dredging project.
The end of Zura’s video shows the soccer fields and adjoining property, including a small lake in the floodway. This flood gives us a glimpse of how a minor rain would affect the proposed high-rise development there.
Until remediation efforts are complete, officials should postpone consideration of the permit. Remediation efforts include:
Rainfalls of the magnitude that caused these five floods should happen about once every 2 years according to Harris County Flood Control. This year they happened five times: 10X greater than expected. A review of peak crest data since 1929 roughly confirms these expectations. In the 80 year since then, the river crested over 50 feet only 40 times.
A review of the same data shows that the river has crested over 57 feet 9 times in the last 80 years and six times since 1994.
I believe excessive sedimentation played a role in this frequency increase. Instead of flooding every other year like this, we’re flooding almost every other month. That’s significant enough to put the brakes on development in the floodway, at least until we understand the extent of the problems and can fix them.
These are my opinions on matters of public policy. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statutes of the Great State of Texas.
Posted by Bob Rehak on December 31, 2018
489 Days since Hurricane Harvey