Last night after posting the third flash flood warning in less than a month, several flood-weary people on FaceBook flashed back to Harvey. They questioned why the SJRA wasn’t releasing water in advance of the storm. I quickly went to SJRA.net and looked at their dashboard. They WERE releasing water. The discussion then morphed into another SJRA bloodletting, borne of fear and frustration over a month of near-continuous flood risk and a year and a half of expensive flood repairs.
I’m not here to defend the SJRA. But I suspected perception and reality were currently out of sync. So I emailed a reader’s comments to Jace Houston, general manager of the SJRA, and asked what they were doing to address his concerns.
Update from Jace Houston of SJRA on Recent Releases
Here is the response I got today. I’m reprinting it word for word.
“As you know, there’s a big information gap between what we do during storm events and what the public perceives. We’re working on some significant items to begin closing that gap.”
“We have an information piece that will go out this afternoon regarding the current rainfall event, but I thought I would mention a couple of items to you just in case you get more inquiries.”
“We’ve been releasing water non-stop since the December 7th rainfall. It takes quite a while to safely lower the lake after its risen a couple of feet above normal level. Obviously the level jumped back up from the Christmas rainfall. Releases went back up to around 7000 cfs, and we’re still at over 3000 cfs. Rainfall has been in the forecast pretty much constantly the last 30 days, so we’re in the mode of trying to safely move it out of the lake before the next storm hits.”
“The forecast for this event is not too bad. Approximately two to three inches across our watershed. We’re only a few inches over 201’, so we should be able to manage this one similarly to the Christmas event.”
Jeff Lindner of Harris County Flood Control issued this update re: current rains at 7 p.m. tonight:
“A band of heavy rainfall with rainfall rates of 1.0-1.5 inches per hour is moving NNE over much of Harris County currently extending along the US 59 corridor. HCFCD gages show rainfall amounts of .75-1.5 inches with this band in an hour or less and this will likely result in some street flooding. Rises on area watersheds are likely, but creeks and bayous will be able to handle this round of rainfall.”
“Additional activity to the SW will likely move into the county over the next few hours.”
Hope that helps! Stay tuned to the National Weather Service, NOAA or your favorite source of weather information.
Here are the latest predictions from NOAA for the area around US59 and rainfall in the last 24 hours for Harris County.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/01/hmmt2_hg.png?fit=600%2C465&ssl=1465600adminadmin2019-01-02 21:13:272019-01-02 21:13:34SJRA Has Released Water Continuously since December 7
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
SJRA Has Released Water Continuously since December 7
Last night after posting the third flash flood warning in less than a month, several flood-weary people on FaceBook flashed back to Harvey. They questioned why the SJRA wasn’t releasing water in advance of the storm. I quickly went to SJRA.net and looked at their dashboard. They WERE releasing water. The discussion then morphed into another SJRA bloodletting, borne of fear and frustration over a month of near-continuous flood risk and a year and a half of expensive flood repairs.
I’m not here to defend the SJRA. But I suspected perception and reality were currently out of sync. So I emailed a reader’s comments to Jace Houston, general manager of the SJRA, and asked what they were doing to address his concerns.
Update from Jace Houston of SJRA on Recent Releases
Here is the response I got today. I’m reprinting it word for word.
“As you know, there’s a big information gap between what we do during storm events and what the public perceives. We’re working on some significant items to begin closing that gap.”
“We have an information piece that will go out this afternoon regarding the current rainfall event, but I thought I would mention a couple of items to you just in case you get more inquiries.”
“We’ve been releasing water non-stop since the December 7th rainfall. It takes quite a while to safely lower the lake after its risen a couple of feet above normal level. Obviously the level jumped back up from the Christmas rainfall. Releases went back up to around 7000 cfs, and we’re still at over 3000 cfs. Rainfall has been in the forecast pretty much constantly the last 30 days, so we’re in the mode of trying to safely move it out of the lake before the next storm hits.”
“The forecast for this event is not too bad. Approximately two to three inches across our watershed. We’re only a few inches over 201’, so we should be able to manage this one similarly to the Christmas event.”
Mark Micheletti emailed this PDF to me last week. Micheletti is one of Kingwood’s two SJRA board members. The letter explains in more detail how they set the level of releases and coordinate with other agencies.
I hope this settles some nerves and reassures people.
Update on Current Conditions and Releases
At approximately 9 p.m. on January 2, the SJRA is releasing 3198 cfs. Harris County’s Flood Warning System shows the largest rainfalls so far during this event are less than 2 inches.
Jeff Lindner of Harris County Flood Control issued this update re: current rains at 7 p.m. tonight:
“A band of heavy rainfall with rainfall rates of 1.0-1.5 inches per hour is moving NNE over much of Harris County currently extending along the US 59 corridor. HCFCD gages show rainfall amounts of .75-1.5 inches with this band in an hour or less and this will likely result in some street flooding. Rises on area watersheds are likely, but creeks and bayous will be able to handle this round of rainfall.”
“Additional activity to the SW will likely move into the county over the next few hours.”
Hope that helps! Stay tuned to the National Weather Service, NOAA or your favorite source of weather information.
Here are the latest predictions from NOAA for the area around US59 and rainfall in the last 24 hours for Harris County.
9 p.m. January 2. Click here for most recent updates.
Posted by Bob Rehak on January 2, 2019
491 Days after Hurricane Harvey
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