WhataBurger in the new HEB shopping center during flooding from Hurricane Harvey. Photo: Courtesy of John Knoerzer.
The Greater Houston Flood Mitigation Consortium issued a region-wide 64-page report on April 5, 2018. It begins with a discussion of the pros and cons of various flood mitigation strategies in general. Then it looks at strategies that apply to each watershed within the region and the equity of funding for each watershed.
The San Jacinto watershed, they say, contains 3% of the region’s population, gets 0% of the budget, and had 14% of the region’s damages.
In-depth engineering studies and science-based hydrologic and ecological assessments to determine the cost, benefits and risks associated with the following proposed flood mitigation strategies:
Making structural alterations to Lake Houston dam and spillway
Dredging along the San Jacinto River and in Lake Houston
Construction of a Montgomery County reservoir system / fourth reservoir
Stricter regulation of sand mining operations, acquisition and complete restoration of land associated with past sand mining operations. Enact stricter state regulations and enforce penalties to shut down illegal mine operations that do not have required permits; strict enforcement of existing rules; require full restoration and/or create an in lieu fee program to finance restoration of closed and abandoned sand mining sites.
Stricter development regulations for the watersheds in the San Jacinto River Basin
Outreach to stakeholders and communities in the San Jacinto River Basin to increase awareness and facilitate greater transparency in reservoir operation and management and development of flood mitigation strategies.
Increased deployment of green infrastructure strategies including conservation easements, land acquisition and LID as population growth and development continues at a rapid pace. Creation of a regional LID guidelines template for use by local and county governments and LID performance criteria needed.
Create a San Jacinto River Community Advisory Council that meets regularly with public operators and functions similarly to community advisory councils in Houston Ship Channel industrial communities.
Stricter floodplain development regulations extending beyond the 500-year floodplain based on Atlas14 rainfall estimates
The entire report is a good read. It’s well designed and filled with helpful illustrations. People seriously interested in flood mitigation should download and read the whole survey. It’s extremely thoughtful and balanced.
Note: We modified this post to reflect feedback from Harris County Flood Control District and the San Jacinto River Authority. HCFCD provided new information showing rainfall totals far upstream. Confusion over the main point of this article also led us to clarify that rain was a contributing factor to the flood, but not the sole cause.
With the bulk of Kingwood’s and Humble’s population living on the West Fork of the San Jacinto River, it’s easy to forget that we have a flooding problem on the East Fork as well. The “East Fork” also includes Peach Creek and Caney Creek watersheds as well as Luce Bayou. And there is no shortage of sand coming down the East Fork from the sand mine on Caney Creek. This sand exacerbates flooding problems in the Kingwood and Huffman areas.
Where Did All The Sand Come From?
The sand mine on Caney Creek in Porter upstream of Kingwood comprises approximately 600 acres. The area where they stockpile sand for shipment comprises approximately 34 acres. The image below, taken on 9/14/17 shows how high the sand stockpile is relative to the height of surrounding trees.
Sand mine in Porter in Montgomery County next to Caney Creek. Water tower in background is at Kingwood Drive and High Valley. The mine is just upstream from East End Park in Kingwood where approximately 30 acres were covered with dunes up to ten feet tall after Harvey.
The next image shows what happened to this stockpile during Harvey. At the top right, you can see how torrential rains eroded the pile. They washed sand down to the bottom left where floodwaters carried it downstream. Note the erosion patterns in the flat area to the left (closest to Caney Creek).
Sand mine in Porter in Montgomery County next to Caney Creek shows signs of massive erosion after Hurricane Harvey. Picture taken on 9/14/18.
Just downstream from this sand mine, one can see sand in the tree tops. It appeared there suddenly after Harvey. The sand in the trees reaches an estimated 20 feet. The giant new sand dune in the river reaches an estimated 15 feet.
Confluence of the east fork of the San Jacinto (background) with Peach and Caney Creeks (foreground). Notice sand deposited by Hurricane Harvey stretching into the tree tops and blocking half the river.
Approximately 30 acres of East End Park, in the background to the right, also flooded with sand. At Eagle Point in the Park, sand dunes exceeded 10 feet and covered approximately a half mile of trails with sand that reached shoulder height at times.
Harvey washed sand downstream from mines in Porter in Montgomery County. After the storm, new dunes up to ten feet high covered 30 acres of Kingwood’s East End Park on the East fork of the San Jacinto River and obliterated trails like this one.
Historical Satellite Images Show Increase in Sand Volume
Some people ask, “Could the sand have come from the creek itself?” Fair question. These historical satellite images help answer it. The first satellite image of this area dates to 4/28/2014. At that point, the mine largely constrained the sand within its perimeter. You see only several small white dunes between it and East End Park, outlined in red.
In January of 2017 before Harvey, Caney Creek (see below) still contained relatively little sand. So far, so good.
After Harvey, in October, 2017, we see a radical change in the volume of sand downstream from the mine. Images taken from the helicopter and from the ground (far above) show the depth of these sand dunes. They appeared immediately after Harvey. In real life, the little white streaks in the creek stretch hundreds of feet and reach tree top height. Moreover, both ground level and helicopter photos show that much sand was hidden from satellite view by the tree canopy.
Effect of Siltation on Caney Creek and East Fork
One question remains – the most important one! How has all this sand affected the flow of Caney Creek and the East Fork? The answer: much like the sand on the West Fork has.
Smaller rains have produced bigger floods because the carrying capacity of the river has been reduced.
How You Can Help
Please contact all Harris County commissioners and the county judge. Their email addresses are on the Links page. Ask them to make sure they have enough money in the upcoming bond election to dredge BOTH the East and West Forks of the San Jacinto. Currently, they are only contemplating dredging the West Fork between US59 and West Lake Houston Parkway.
Bill Fowler, co-chair of the Kingwood Grass-Roots Flood Initiative found these statistics. Our thanks to Bill.
Posted on 4/3/18, 217 days since Hurricane Harvey.
Revised 4/10/18, 224 days since Hurricane Harvey.
00adminadmin2018-04-03 23:14:292018-04-10 16:45:29Five inches of rain helped create the third largest flood in 16 years and sand downstream made it worse
Beginning March 27, 2018, the City of Houston lowered the level of Lake Houston in anticipation of flash flooding. The storm hit Kingwood in the afternoon of the 28th and was over by the morning of the 29th According to Harris County Flood Control rain gages, we received 2.64 inches of rain at the Kingwood Country Club and 3.36 inches at the US59 bridge. Areas upstream received as much as 5.5 inches. An average across the watershed was close to 4.
Thank you, Dave Martin and Sylvester Turner!
Mayor Sylvester Turner and Council Member Dave Martin should be congratulated on their decision to lower Lake Houston. Some low-lying areas like River Grove Park flooded. However, as of this writing, I’m not aware of any homes that flooded. Surely there would have been major property damage, given all the siltation from Hurricane Harvey, had the lake been at its normal level.
How the rain affected different parts of Kingwood
The underpass at the 59 bridge was closed due to high water early in the morning on the 29th. This is a perennial choke point. It has gotten worse since Harvey.
At Scenic Shores in Kings Point, the river was well within its banks thanks to the decision to lower the lake.
How much was it lowered? 2.5 feet according to the Coastal Water Authority.
Below is a photo taken last night in Kingwood Greens. It shows vast expanses of sand before the rain started. There were no reports of flooding in Kingwood Greens today, again, thanks in large part to the decision to lower the lake before the storm.
In Kings Lake Estates on the south side of the San Jacinto River, across from Kingwood Greens, the water got close. A resident sent this pic.
The homeowner above stated, “I am literally stunned how high the water is at my property right now even though the lake level was extremely low only 24 hours ago….and only after a modest rain storm last night.” To underscore the need to begin dredging immediately, he added, “This has NEVER happened before with such a minor rain event!”
Worst Flooding At River Grove Park
River Grove still has that massive sand bar blocking the drainage ditch. Water backed up behind that and flooded the park – for the second time within a month! See four images below.
As of 2:30 PM on March 29th, the disc golf course, playing fields, boat dock area and boardwalk at River Grove were totally under water. Additionally, about a third of the parking lot was under water and the flood level was continuing to rise.
All in all though, we lucked out with this storm largely because of the decision to lower the lake. Without that, flooding would have been much worse.
Anxiously Awaiting Dredging
Yesterday, the county approved money to begin dredging this area. Hopefully that will help cure the flooding woes at River Grove and give us a great margin of safety elsewhere.
As bad as these pictures look, about three weeks ago, on one-fifth the amount of rain that we received last night, the flooding was far worse.Before Harvey and the giant sand blockage at the base of the drainage ditch, River Grove could take twice as much rain without this much flooding.
As the resident who owned the gazebo above said, “With no major dredging, Kingwood residents better start praying every single day that we don’t get a tropical storm or even minor hurricane. We need dredging SOON!”
Posted by Bob Rehak on March 29, 2018
212 days since Hurricane Harvey
00adminadmin2018-03-29 17:42:432023-11-22 09:04:24Impact of March 28/29 Rain and Lower Lake Level on Kingwood
Greater Houston Flood Mitigation Consortium Issues Recommendations for San Jacinto Watershed
WhataBurger in the new HEB shopping center during flooding from Hurricane Harvey. Photo: Courtesy of John Knoerzer.
The Greater Houston Flood Mitigation Consortium issued a region-wide 64-page report on April 5, 2018. It begins with a discussion of the pros and cons of various flood mitigation strategies in general. Then it looks at strategies that apply to each watershed within the region and the equity of funding for each watershed.
The Consortium’s discussion of recommendations for the San Jacinto watershed begins on page 48 and continues on page 49. Because the complete report is more than a 130 megabyte download, I quote their recommendations for us below:
The entire report is a good read. It’s well designed and filled with helpful illustrations. People seriously interested in flood mitigation should download and read the whole survey. It’s extremely thoughtful and balanced.
Here is the Houston Chronicle’s take on the Greater Houston Flood Mitigation Consortium’s report.
Posted April 6, 2018, 219 Days After Hurricane Harvey.
Five inches of rain helped create the third largest flood in 16 years and sand downstream made it worse
Note: We modified this post to reflect feedback from Harris County Flood Control District and the San Jacinto River Authority. HCFCD provided new information showing rainfall totals far upstream. Confusion over the main point of this article also led us to clarify that rain was a contributing factor to the flood, but not the sole cause.
The flood on the East Fork of the San Jacinto last weekend (3/31/2018) crested at 66.1 ft. in New Caney. This was the 10th highest historical crest in the last 35 years – after a relatively minor rainfall event – 4.33 inches as measured on Caney Creek at 2090. That’s the only rain gage operated by the San Jacinto River Authority on the East Fork. Last weekend’s flood was also the third highest in the last 16 years on the East Fork. In fairness, it rained more upstream than at the gauge. HCFCD provided this rainfall map to show the distribution and said that rainfall averaged five inches across the watershed.
The East Fork: The Forgotten Flooding Problem
With the bulk of Kingwood’s and Humble’s population living on the West Fork of the San Jacinto River, it’s easy to forget that we have a flooding problem on the East Fork as well. The “East Fork” also includes Peach Creek and Caney Creek watersheds as well as Luce Bayou. And there is no shortage of sand coming down the East Fork from the sand mine on Caney Creek. This sand exacerbates flooding problems in the Kingwood and Huffman areas.
Where Did All The Sand Come From?
The sand mine on Caney Creek in Porter upstream of Kingwood comprises approximately 600 acres. The area where they stockpile sand for shipment comprises approximately 34 acres. The image below, taken on 9/14/17 shows how high the sand stockpile is relative to the height of surrounding trees.
Sand mine in Porter in Montgomery County next to Caney Creek. Water tower in background is at Kingwood Drive and High Valley. The mine is just upstream from East End Park in Kingwood where approximately 30 acres were covered with dunes up to ten feet tall after Harvey.
The next image shows what happened to this stockpile during Harvey. At the top right, you can see how torrential rains eroded the pile. They washed sand down to the bottom left where floodwaters carried it downstream. Note the erosion patterns in the flat area to the left (closest to Caney Creek).
Sand mine in Porter in Montgomery County next to Caney Creek shows signs of massive erosion after Hurricane Harvey. Picture taken on 9/14/18.
Just downstream from this sand mine, one can see sand in the tree tops. It appeared there suddenly after Harvey. The sand in the trees reaches an estimated 20 feet. The giant new sand dune in the river reaches an estimated 15 feet.
Confluence of the east fork of the San Jacinto (background) with Peach and Caney Creeks (foreground). Notice sand deposited by Hurricane Harvey stretching into the tree tops and blocking half the river.
Approximately 30 acres of East End Park, in the background to the right, also flooded with sand. At Eagle Point in the Park, sand dunes exceeded 10 feet and covered approximately a half mile of trails with sand that reached shoulder height at times.
Harvey washed sand downstream from mines in Porter in Montgomery County. After the storm, new dunes up to ten feet high covered 30 acres of Kingwood’s East End Park on the East fork of the San Jacinto River and obliterated trails like this one.
Historical Satellite Images Show Increase in Sand Volume
Some people ask, “Could the sand have come from the creek itself?” Fair question. These historical satellite images help answer it. The first satellite image of this area dates to 4/28/2014. At that point, the mine largely constrained the sand within its perimeter. You see only several small white dunes between it and East End Park, outlined in red.
In January of 2017 before Harvey, Caney Creek (see below) still contained relatively little sand. So far, so good.
After Harvey, in October, 2017, we see a radical change in the volume of sand downstream from the mine. Images taken from the helicopter and from the ground (far above) show the depth of these sand dunes. They appeared immediately after Harvey. In real life, the little white streaks in the creek stretch hundreds of feet and reach tree top height. Moreover, both ground level and helicopter photos show that much sand was hidden from satellite view by the tree canopy.
Effect of Siltation on Caney Creek and East Fork
One question remains – the most important one! How has all this sand affected the flow of Caney Creek and the East Fork? The answer: much like the sand on the West Fork has.
How You Can Help
Please contact all Harris County commissioners and the county judge. Their email addresses are on the Links page. Ask them to make sure they have enough money in the upcoming bond election to dredge BOTH the East and West Forks of the San Jacinto. Currently, they are only contemplating dredging the West Fork between US59 and West Lake Houston Parkway.
Bill Fowler, co-chair of the Kingwood Grass-Roots Flood Initiative found these statistics. Our thanks to Bill.
Posted on 4/3/18, 217 days since Hurricane Harvey.
Revised 4/10/18, 224 days since Hurricane Harvey.
Impact of March 28/29 Rain and Lower Lake Level on Kingwood
Beginning March 27, 2018, the City of Houston lowered the level of Lake Houston in anticipation of flash flooding. The storm hit Kingwood in the afternoon of the 28th and was over by the morning of the 29th According to Harris County Flood Control rain gages, we received 2.64 inches of rain at the Kingwood Country Club and 3.36 inches at the US59 bridge. Areas upstream received as much as 5.5 inches. An average across the watershed was close to 4.
Thank you, Dave Martin and Sylvester Turner!
Mayor Sylvester Turner and Council Member Dave Martin should be congratulated on their decision to lower Lake Houston. Some low-lying areas like River Grove Park flooded. However, as of this writing, I’m not aware of any homes that flooded. Surely there would have been major property damage, given all the siltation from Hurricane Harvey, had the lake been at its normal level.
How the rain affected different parts of Kingwood
The underpass at the 59 bridge was closed due to high water early in the morning on the 29th. This is a perennial choke point. It has gotten worse since Harvey.
At Scenic Shores in Kings Point, the river was well within its banks thanks to the decision to lower the lake.
How much was it lowered? 2.5 feet according to the Coastal Water Authority.
Below is a photo taken last night in Kingwood Greens. It shows vast expanses of sand before the rain started. There were no reports of flooding in Kingwood Greens today, again, thanks in large part to the decision to lower the lake before the storm.
In Kings Lake Estates on the south side of the San Jacinto River, across from Kingwood Greens, the water got close. A resident sent this pic.
The homeowner above stated, “I am literally stunned how high the water is at my property right now even though the lake level was extremely low only 24 hours ago….and only after a modest rain storm last night.” To underscore the need to begin dredging immediately, he added, “This has NEVER happened before with such a minor rain event!”
Worst Flooding At River Grove Park
River Grove still has that massive sand bar blocking the drainage ditch. Water backed up behind that and flooded the park – for the second time within a month! See four images below.
As of 2:30 PM on March 29th, the disc golf course, playing fields, boat dock area and boardwalk at River Grove were totally under water. Additionally, about a third of the parking lot was under water and the flood level was continuing to rise.
Anxiously Awaiting Dredging
Yesterday, the county approved money to begin dredging this area. Hopefully that will help cure the flooding woes at River Grove and give us a great margin of safety elsewhere.
As bad as these pictures look, about three weeks ago, on one-fifth the amount of rain that we received last night, the flooding was far worse. Before Harvey and the giant sand blockage at the base of the drainage ditch, River Grove could take twice as much rain without this much flooding.
As the resident who owned the gazebo above said, “With no major dredging, Kingwood residents better start praying every single day that we don’t get a tropical storm or even minor hurricane. We need dredging SOON!”
Posted by Bob Rehak on March 29, 2018
212 days since Hurricane Harvey