5/17/2024 – The Hallett sand mine on the San Jacinto West Fork appears to have dug a trench across the maintenance road of its settling pond to lower the pond’s level. Murky wastewater is draining into the West Fork while the SJRA is currently releasing 10,875 cubic feet per second (CFS) from Lake Conroe in the wake of yesterday’s heavy rains.
Sediment released from the mine is being picked up by the Lake Conroe water and carried downstream. Note below how sediment has discolored the West Fork.
Picture taken 5/17/24, at the confluence of the West Fork, Spring Creek and Cypress Creek. Cypress joins Spring slightly upstream on the left.The branch on the right is immediately downstream from 20 square miles of sand mines between US59 and I-45.
Where The Sludge is Coming From
In the last few weeks I’ve posted extensively about how the West Fork has breached the dikes of a pit formerly owned by Hallett. As of this afternoon, the river continues to run through that pit. No attempt has been made by the new owner to re-establish the dikes. And that certainly contributes to downstream sedimentation.
But this afternoon, I discovered an additional source of sedimentation thanks to a tip from a nearby fishermen who stumbled across a breach in Hallett’s settling pond. See video below.
Video supplied by fishermen.
It’s hard to get a sense of the location from the close up, so here’s the location of the breach in a satellite image from Google Earth.
General location of breach and path to river in red oval.
And here’s a more detailed look at the path the water took on its way to the river.
Looking N. Silty water leaves Hallett’s settling pond through a trench dug in the tree-line. From there it flows through an abandoned sand mine and then through another breach into the West Fork.Reverse angle shows silty water flowing out of Hallett settling pondinto abandoned neighboring mine.Detail cropped from shot above shows how heavy equipment worked the area.Looking S downstream. Abandoned mine on left, West Fork in middle and breach through another pit on right.
Timing of Release Should Raise Eyebrows
The timing of this release is suspect: Friday afternoon just before regulators headed home for the weekend.
I’ve documented a history of breaches from this pond dating back to 2019 and the fishermen say they’ve seen breaches before that.
Hallett flushed water from this and other ponds after the January floods in 2024 but via different routes.
Lest you think I’m picking on Hallett, it isn’t the only sand mine emptying its settling pond into the West Fork.
I also documented an instance when the West Fork ran white from a release at the LMI Moorhead Mine upstream from Hallett. TCEQ estimated they released 56 million gallons of sludge into the river. That pond dropped 3-4 feet according to the TCEQ.
Regular Occurrence
The montage below shows the confluence of the West Fork and Spring/Cypress Creeks from different angles on different days. In all cases, the polluted branch was the West Fork. I took these shots while photographing West Fork sand mines from a rented helicopter.
A former West Fork mine operator and a former water quality manager for the City of Houston tell me that releasing sediment-laden water under the cover of floods is standard operating procedure for many mines on the West Fork.
Who Will Bear the Cost of Clean Up, Dredging?
Think this doesn’t affect you? It affects your water quality and the cost of cleaning it up. Lake Houston supplies drinking water for more than two million people.
And if you live between the mines and Lake Houston, it probably will affect you another way.
Most sediment moves during floods. During Harvey, the West Fork swept through 20 square miles of sand mines between I-45 and I-69. According to the Army Corps, deposited sediment blocked the West Fork by 90%. That reduced the conveyance of the river and caused water to rise into homes and businesses. Almost 20,000 flooded in the Humble/Kingwood area.
Since then, taxpayers have spent more than $200 million on dredging. And the City is getting ready to launch another $34 million dredging program.
However, that program won’t address the mouth of the Kingwood Diversion Ditch at the River Grove Park boat launch.
KSA has obtained bids north of $800,000 to dredge the blocked area. Spending that kind of money will be necessary to keep the KSA boat launch open. It has become badly blocked by sediment during two floods since the start of the year.
Here’s what that area looked like yesterday afternoon when the SJRA release rate was closer to 1500 CFS.Water level in river was still up about a footabove normal.
Living with sediment is all part of life on the river. But dredging intervals at River Grove have gone from 8 years before Harvey to 4 to 2 years since Harvey.
If this continues, KSA may be forced debate whether it can afford to keep the boat docks open.
Harris County Precinct 3 Commissioner Tom Ramsey, PE is trying to work with upstream authorities to reduce sedimentation that can lead to flooding. But it’s an uphill slog. No pun intended.
Posted by Bob Rehak on 5/17/2024
2053 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.
4:30 PM May 16, 2024 – The National Weather Service has issued a trio of alerts that affect the Lake Houston Area. A tornado watch, flood warning, and flood watch are all simultaneously in effect.
Scene Capture from RadarScope Pro at 4:12PM 5/16/24
Tornado Watch
The three include a tornado watch until 10 PM tonight. The watch includes all counties in the Houston Region and then some.
AUSTIN BRAZORIA BRAZOS BURLESON CHAMBERS COLORADO FORT BEND GALVESTON GRIMES HARDIN HARRIS HOUSTON JASPER JEFFERSON LIBERTY MADISON MONTGOMERY NEWTON ORANGE POLK SAN JACINTO TRINITY TYLER WALKER WALLER WASHINGTON WHARTON
Update: At 5:50 PM, issued a tornado warning for NW Harris, Austin and Waller Counties. They spotted rotation on radar. The warning will expire at 6PM, but it speaks to the severity of these storms.
Flood Warning
The Weather Service has also issued a flood warning for the San Jacinto East Fork. Predicted crests are increasing from minor to moderate levels near FM1485. This could affect people in Harris, Montgomery and Liberty Counties. Some are still cleaning up from the flood two weeks ago.
Flood Watch in Wider Area
Finally, a flood watch has been issued due to excessive rainfall across the region. This one could trigger flooding on other creeks, streams and bayous. The watch area includes:
This watch is primarily due to excessive rainfall associated with the approaching storm. It could drop 2-4″ across a wide area, with isolated totals up to 6-8″.
Lake Houston is in the area of highest risk – Level 4 – for excessive rainfall.
National Weather Service (See below.)
Flash Flooding Possible
High intensity rains could produce flash flooding that makes driving dangerous.
The ground is already super saturated from previous rains. “There is just nowhere for the water to go,” said Harris County Meteorologist Jeff Lindner.
According to Lindner, “Widespread rainfall amounts of 2-4″ will be likely north of HWY 105. Isolated totals could reach upwards to 6-8 inches. Amounts will decrease toward the south with totals near the coast less than 1 inch. This will virtually be a carbon copy of the last several rainfall events in terms of location and amounts.”
Lake Report
Lake Conroe was releasing 1590 cubic feet per second until the noon hour today. Then, the SJRA stopped releasing water give the Coastal Water Authority a chance to reduce the level of Lake Houston. Lake Houston continues to release water.
Lake Conroe operators hoped they had enough capacity in the Lake to absorb the expected influx of water. But at 4:30PM, the resumed releasing 1587 CFS.
They also announced that they will “pass through storm water and runoff received in the Upper San Jacinto River Basin until Lake Conroe returns to conservation pool.” (201 feet)
Both lakes just returned close to their normal levels from the floods in early May. However, Lake Houston is still a few inches above normal.
Total inflows into Lake Houston are at 6,627 cfs and outflows are at 8,960 cfs. Lake Houston gates have and will remain open until the gate that is stuck partially open is repaired.
Impact on Sedimentation
Most sediment moves during floods. And the West Fork sure has been piling up sediment lately. KSA just completed a sonar survey in River Grove Park where the Kingwood Diversion Ditch enters the West Fork.
Before the last storm, sand had built up at the mouth so that only about two feet of clearance was available for boats. After the last storm, sand is poking up even closer to the surface…and the river is still about a half foot above normal.
Even with water up about a half foot, you can see sand bars lurking just below surface at the River Grove boat launch.
The City of Houston is getting ready to launch a new $34 million dredging program between Kings Point and FM1960.
DRC/Callan Marine mobilizing for new dredging program south of Forest Cove Pool.
Unfortunately, the new City program won’t include the mouth of the Diversion Ditch. KSA will have to hire its own dredger to keep the boat docks open.
KSA’s dredging interval has gone from 8 to 4 to 2 years. It sure seems as though it would be less expensive if we didn’t have West Fork floods flowing through sand pits.
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/2024/05/4PM-Front.jpg?fit=1100%2C632&ssl=16321100adminadmin2024-05-16 16:27:222024-05-17 22:48:00Tornado Watch, Flood Warning, Flood Watch In Effect
A report issued by Harris County’s Meteorologist Jeff Lindner puts the May 2024 flood into historical perspective.
Significant flooding occurred along the West and East Forks of the San Jacinto River as well as the lower San Jacinto River below Lake Houston.
While rainfall occurred over a 7-day period, the most intense rainfall in Harris County fell on Thursday, May 2nd. Lindner’s report starts by covering the rainfall totals and intensity during different lengths of time. Then, he discusses the resulting flood heights and impacts.
Locations of 7-day rainfall totals between April 28 and May 5. Upstream areas received twice as much as Lake Houston.
Total Rainfall in 7-Day Period
Total rainfall amounts for the seven-day period averaged 10.0-17.0 inches across the extreme northern and northeastern portions of Harris County. Southern and central Montgomery County were also affected as well as northern Liberty County.
A maximum 7-day rainfall of 16.8 inches was recorded on the East Fork of the San Jacinto River at FM 1485.
The table below indicates maximum rainfall for Harris County gages.
Maximum rainfalls for different periods from 5 minutes to 7 days.
Using Atlas-14 Rainfall Exceedance Probability Tables, Lindner says rainfall during the 7-day time period ranged from:
5- to 10-year events on the San Jacinto West and East Forks as well as below Lake Houston
2- to 5-year events on Cedar Bayou.
2- to 10-year events along Luce Bayou.
Maximum 2-Day and 3-Hour Rainfall Totals
The max rainfall for those same watersheds during the peak 48-hours ranged from 2- to 10-year events.
During the peak 3-hour time period, however, gages on Willow Creek, Spring Creek, Luce Bayou, Cedar Bayou, and the San Jacinto recorded 25- to 50-year rains. The short, high-intensity rains resulted in deep street and flash flooding.
North of Harris County, the rainfall got much more intense.
Locations of Heaviest Rainfall
The majority of the heavy to excessive rainfall occurred across areas north and northeast of Harris County. This was across the headwaters of the West and East Forks of the San Jacinto River, Luce Bayou, and Lake Creek.
Rainfall amounts over the 7-day period averaged 15.0-18.0 inches over southern Walker and northern Montgomery County which drain into Lake Conroe. They averaged 15.0-20.0 inches across eastern Walker County, northern Montgomery County, and San Jacinto County which drain into the East Fork of the San Jacinto River.
“No two storm events are exactly the same with respect to the location, duration, and maximum totals of rainfall.”
Jeff Lindner, Harris County Meteorologist
Comparisons with Other Storms
The May 2024 rainfall had some similarities to the October 1994 flood. Nearly 30 inches fell across Lake Creek and the northwest portions of the Spring Creek watersheds in 1994. In 2024, the highest totals occurred farther to the north – from north of Lake Conroe to northwest of Lake Livingston.
In those locations, the rainfall exceeded 1994. That resulted in near record inflows for both Lake Conroe and Lake Livingston.
Comparison of maximum rainfall totals in different time periods for different storms.Note especially the totals for 1-hour and less.
Flooding in Historical Perspective
Rainfall is only a starting point when investigating flooding. You must also look at rainfall distribution, intensity, longevity, previous heavy rainfall, ground saturation, already swollen watersheds, and convergence of peak flows.
Much of the upper portions of the San Jacinto basin stretch across parts of Montgomery, Walker, and San Jacinto Counties. In April, they experienced rainfall 150% to 500% above normal.
Rainfall on April 28th-29th primed already wet soils for maximum run-off. Then, those same areas received additional excessive rainfall on May 1st-2nd. The second episode generated widespread and significant flash flooding and run-off into the rivers and creeks that drain to Lake Houston.
Second Highest Peak on East Fork
The East Fork exceeded the expected elevation of a 500-year storm. At FM1485, only Harvey exceeded the May peak.
San Jacinto East Fork peaks at FM1485.
Five-hundred year flooding on a 20-year rain resulted when peaks from different rounds of rainfall piled on top of each other from different watersheds.
Fifth Highest Peak on West Fork
West Fork flooding was less extreme. This was the fifth highest flooding on the West Fork since 1994. The May flood qualified as a 10- to 50-year storm based on gage readings at US59.
Five highest peaks on San Jacinto West Fork since 1994.
Fourth Highest Peak at Lake Houston Dam
The height of water going over the spillway at the Lake Houston Dam was the 4th highest peak since 1979.
Downstream at Highway 90, residents saw the 9th highest peak since 1979. Downstream areas saw between a 10-year and 50-year flood.
Third Highest Volume of Stormwater Flowing Into Lake Houston
The table below summarizes volumes of water in cubic feet per second flowing into Lake Houston from the various watersheds during different storms. This May’s event was the 3rd highest total since 1994. Only Harvey and October 1994 surpassed it.
Water flowing into Lake Houston in different storms since 1994. This May was 3rd largest volume.
House Flooding Estimates
Flood depths ranged from 6 inches to several feet in some of the lowest lying homes. The damage numbers below apply only to Harris County. The numbers were supplied by City of Houston and Harris County Engineering.
20 homes flooded with an additional 16 having water in sheds, garages, or other non-living areas on the West Fork.
32 homes flooded with an additional 8 having water water in non-living areas on the East Fork.
Upstream, the flood damage in Montgomery and Liberty Counties was much greater. However, I do not have final totals for those areas yet.
Maps, Tables Galore
Lindner’s report also includes 15 pages of rainfall intensity maps and tables for different watersheds and gages. It’s a treasure trove of information including high water marks. Click here for the full report. For future reference, that’s under the link to the Major Storms tab on the Reports Page. You can compare full reports on other storms there.
West Fork Sand Mine Sending Sediment Downstream from Settling Pond
5/17/2024 – The Hallett sand mine on the San Jacinto West Fork appears to have dug a trench across the maintenance road of its settling pond to lower the pond’s level. Murky wastewater is draining into the West Fork while the SJRA is currently releasing 10,875 cubic feet per second (CFS) from Lake Conroe in the wake of yesterday’s heavy rains.
Sediment released from the mine is being picked up by the Lake Conroe water and carried downstream. Note below how sediment has discolored the West Fork.
Where The Sludge is Coming From
In the last few weeks I’ve posted extensively about how the West Fork has breached the dikes of a pit formerly owned by Hallett. As of this afternoon, the river continues to run through that pit. No attempt has been made by the new owner to re-establish the dikes. And that certainly contributes to downstream sedimentation.
But this afternoon, I discovered an additional source of sedimentation thanks to a tip from a nearby fishermen who stumbled across a breach in Hallett’s settling pond. See video below.
It’s hard to get a sense of the location from the close up, so here’s the location of the breach in a satellite image from Google Earth.
And here’s a more detailed look at the path the water took on its way to the river.
Timing of Release Should Raise Eyebrows
The timing of this release is suspect: Friday afternoon just before regulators headed home for the weekend.
I’ve documented a history of breaches from this pond dating back to 2019 and the fishermen say they’ve seen breaches before that.
Hallett flushed water from this and other ponds after the January floods in 2024 but via different routes.
Lest you think I’m picking on Hallett, it isn’t the only sand mine emptying its settling pond into the West Fork.
I also documented an instance when the West Fork ran white from a release at the LMI Moorhead Mine upstream from Hallett. TCEQ estimated they released 56 million gallons of sludge into the river. That pond dropped 3-4 feet according to the TCEQ.
Regular Occurrence
The montage below shows the confluence of the West Fork and Spring/Cypress Creeks from different angles on different days. In all cases, the polluted branch was the West Fork. I took these shots while photographing West Fork sand mines from a rented helicopter.
A former West Fork mine operator and a former water quality manager for the City of Houston tell me that releasing sediment-laden water under the cover of floods is standard operating procedure for many mines on the West Fork.
Who Will Bear the Cost of Clean Up, Dredging?
Think this doesn’t affect you? It affects your water quality and the cost of cleaning it up. Lake Houston supplies drinking water for more than two million people.
And if you live between the mines and Lake Houston, it probably will affect you another way.
Most sediment moves during floods. During Harvey, the West Fork swept through 20 square miles of sand mines between I-45 and I-69. According to the Army Corps, deposited sediment blocked the West Fork by 90%. That reduced the conveyance of the river and caused water to rise into homes and businesses. Almost 20,000 flooded in the Humble/Kingwood area.
Since then, taxpayers have spent more than $200 million on dredging. And the City is getting ready to launch another $34 million dredging program.
However, that program won’t address the mouth of the Kingwood Diversion Ditch at the River Grove Park boat launch.
KSA has obtained bids north of $800,000 to dredge the blocked area. Spending that kind of money will be necessary to keep the KSA boat launch open. It has become badly blocked by sediment during two floods since the start of the year.
Living with sediment is all part of life on the river. But dredging intervals at River Grove have gone from 8 years before Harvey to 4 to 2 years since Harvey.
If this continues, KSA may be forced debate whether it can afford to keep the boat docks open.
Harris County Precinct 3 Commissioner Tom Ramsey, PE is trying to work with upstream authorities to reduce sedimentation that can lead to flooding. But it’s an uphill slog. No pun intended.
Posted by Bob Rehak on 5/17/2024
2053 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.
Tornado Watch, Flood Warning, Flood Watch In Effect
4:30 PM May 16, 2024 – The National Weather Service has issued a trio of alerts that affect the Lake Houston Area. A tornado watch, flood warning, and flood watch are all simultaneously in effect.
Tornado Watch
The three include a tornado watch until 10 PM tonight. The watch includes all counties in the Houston Region and then some.
Update: At 5:50 PM, issued a tornado warning for NW Harris, Austin and Waller Counties. They spotted rotation on radar. The warning will expire at 6PM, but it speaks to the severity of these storms.
Flood Warning
The Weather Service has also issued a flood warning for the San Jacinto East Fork. Predicted crests are increasing from minor to moderate levels near FM1485. This could affect people in Harris, Montgomery and Liberty Counties. Some are still cleaning up from the flood two weeks ago.
Flood Watch in Wider Area
Finally, a flood watch has been issued due to excessive rainfall across the region. This one could trigger flooding on other creeks, streams and bayous. The watch area includes:
This watch is primarily due to excessive rainfall associated with the approaching storm. It could drop 2-4″ across a wide area, with isolated totals up to 6-8″.
Flash Flooding Possible
High intensity rains could produce flash flooding that makes driving dangerous.
The ground is already super saturated from previous rains. “There is just nowhere for the water to go,” said Harris County Meteorologist Jeff Lindner.
According to Lindner, “Widespread rainfall amounts of 2-4″ will be likely north of HWY 105. Isolated totals could reach upwards to 6-8 inches. Amounts will decrease toward the south with totals near the coast less than 1 inch. This will virtually be a carbon copy of the last several rainfall events in terms of location and amounts.”
Lake Report
Lake Conroe was releasing 1590 cubic feet per second until the noon hour today. Then, the SJRA stopped releasing water give the Coastal Water Authority a chance to reduce the level of Lake Houston. Lake Houston continues to release water.
Lake Conroe operators hoped they had enough capacity in the Lake to absorb the expected influx of water. But at 4:30PM, the resumed releasing 1587 CFS.
They also announced that they will “pass through storm water and runoff received in the Upper San Jacinto River Basin until Lake Conroe returns to conservation pool.” (201 feet)
Both lakes just returned close to their normal levels from the floods in early May. However, Lake Houston is still a few inches above normal.
Total inflows into Lake Houston are at 6,627 cfs and outflows are at 8,960 cfs. Lake Houston gates have and will remain open until the gate that is stuck partially open is repaired.
Impact on Sedimentation
Most sediment moves during floods. And the West Fork sure has been piling up sediment lately. KSA just completed a sonar survey in River Grove Park where the Kingwood Diversion Ditch enters the West Fork.
Before the last storm, sand had built up at the mouth so that only about two feet of clearance was available for boats. After the last storm, sand is poking up even closer to the surface…and the river is still about a half foot above normal.
The City of Houston is getting ready to launch a new $34 million dredging program between Kings Point and FM1960.
Unfortunately, the new City program won’t include the mouth of the Diversion Ditch. KSA will have to hire its own dredger to keep the boat docks open.
KSA’s dredging interval has gone from 8 to 4 to 2 years. It sure seems as though it would be less expensive if we didn’t have West Fork floods flowing through sand pits.
For Real-Time Information
To monitor:
Posted by Bob Rehak on 5/16/24 at 4:30 PM
2452 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.
HCFCD Report Puts May 2024 Flood in Historical Perspective
A report issued by Harris County’s Meteorologist Jeff Lindner puts the May 2024 flood into historical perspective.
Significant flooding occurred along the West and East Forks of the San Jacinto River as well as the lower San Jacinto River below Lake Houston.
While rainfall occurred over a 7-day period, the most intense rainfall in Harris County fell on Thursday, May 2nd. Lindner’s report starts by covering the rainfall totals and intensity during different lengths of time. Then, he discusses the resulting flood heights and impacts.
Total Rainfall in 7-Day Period
Total rainfall amounts for the seven-day period averaged 10.0-17.0 inches across the extreme northern and northeastern portions of Harris County. Southern and central Montgomery County were also affected as well as northern Liberty County.
A maximum 7-day rainfall of 16.8 inches was recorded on the East Fork of the San Jacinto River at FM 1485.
The table below indicates maximum rainfall for Harris County gages.
Using Atlas-14 Rainfall Exceedance Probability Tables, Lindner says rainfall during the 7-day time period ranged from:
Maximum 2-Day and 3-Hour Rainfall Totals
The max rainfall for those same watersheds during the peak 48-hours ranged from 2- to 10-year events.
During the peak 3-hour time period, however, gages on Willow Creek, Spring Creek, Luce Bayou, Cedar Bayou, and the San Jacinto recorded 25- to 50-year rains. The short, high-intensity rains resulted in deep street and flash flooding.
North of Harris County, the rainfall got much more intense.
Locations of Heaviest Rainfall
The majority of the heavy to excessive rainfall occurred across areas north and northeast of Harris County. This was across the headwaters of the West and East Forks of the San Jacinto River, Luce Bayou, and Lake Creek.
Rainfall amounts over the 7-day period averaged 15.0-18.0 inches over southern Walker and northern Montgomery County which drain into Lake Conroe. They averaged 15.0-20.0 inches across eastern Walker County, northern Montgomery County, and San Jacinto County which drain into the East Fork of the San Jacinto River.
Comparisons with Other Storms
The May 2024 rainfall had some similarities to the October 1994 flood. Nearly 30 inches fell across Lake Creek and the northwest portions of the Spring Creek watersheds in 1994. In 2024, the highest totals occurred farther to the north – from north of Lake Conroe to northwest of Lake Livingston.
In those locations, the rainfall exceeded 1994. That resulted in near record inflows for both Lake Conroe and Lake Livingston.
Flooding in Historical Perspective
Rainfall is only a starting point when investigating flooding. You must also look at rainfall distribution, intensity, longevity, previous heavy rainfall, ground saturation, already swollen watersheds, and convergence of peak flows.
Much of the upper portions of the San Jacinto basin stretch across parts of Montgomery, Walker, and San Jacinto Counties. In April, they experienced rainfall 150% to 500% above normal.
Rainfall on April 28th-29th primed already wet soils for maximum run-off. Then, those same areas received additional excessive rainfall on May 1st-2nd. The second episode generated widespread and significant flash flooding and run-off into the rivers and creeks that drain to Lake Houston.
Second Highest Peak on East Fork
The East Fork exceeded the expected elevation of a 500-year storm. At FM1485, only Harvey exceeded the May peak.
Five-hundred year flooding on a 20-year rain resulted when peaks from different rounds of rainfall piled on top of each other from different watersheds.
Fifth Highest Peak on West Fork
West Fork flooding was less extreme. This was the fifth highest flooding on the West Fork since 1994. The May flood qualified as a 10- to 50-year storm based on gage readings at US59.
Fourth Highest Peak at Lake Houston Dam
The height of water going over the spillway at the Lake Houston Dam was the 4th highest peak since 1979.
Downstream at Highway 90, residents saw the 9th highest peak since 1979. Downstream areas saw between a 10-year and 50-year flood.
Third Highest Volume of Stormwater Flowing Into Lake Houston
The table below summarizes volumes of water in cubic feet per second flowing into Lake Houston from the various watersheds during different storms. This May’s event was the 3rd highest total since 1994. Only Harvey and October 1994 surpassed it.
House Flooding Estimates
Flood depths ranged from 6 inches to several feet in some of the lowest lying homes. The damage numbers below apply only to Harris County. The numbers were supplied by City of Houston and Harris County Engineering.
Upstream, the flood damage in Montgomery and Liberty Counties was much greater. However, I do not have final totals for those areas yet.
Maps, Tables Galore
Lindner’s report also includes 15 pages of rainfall intensity maps and tables for different watersheds and gages. It’s a treasure trove of information including high water marks. Click here for the full report. For future reference, that’s under the link to the Major Storms tab on the Reports Page. You can compare full reports on other storms there.
Many thanks to Jeff Lindner and his team. They keep hundreds of gages around Harris Country watersheds working to provide timely, life-saving information via the Harris County Flood Warning System.
Posted by Bob Rehak on 5/15/24
2451 Days since Hurricane Harvey