5/2/24 Noon Update: Since publishing this, Lake Conroe has continued to rise and the SJRA has increased the release rate to 66,100 CFS. – Heavy storms dumped 10-12 inches of rain in isolated areas north of Lake Conroe last night. Most areas experienced 5-7 inches. As a result, Lake Conroe has increased its release rate to 60,455 cubic feet per second and it could go higher.
The area north of Lake Conroe has received more than 17 inches in the last week.
Engineers are currently modeling several different scenarios. The current inflow is more than two times greater than the outflow. The current release rate is already the second highest in the history of Lake Conroe.
According to Jeff Lindner, Harris County meteorologist, significant flash flooding is ongoing from north of HWY 105 to southern Montgomery County and the northern portions of Harris County.
At 8:27 am, radar showed the storm had moved into northern Harris, and northern Liberty Counties.
RadarScope Pro Screen Capture at 8:23 AM, 5.2.24, Orange indicates 5″.
It dumped 6 inches of rain in my gauge in two hours. And the total is still climbing.
Such high hourly rainfall rates result in street flooding. Lindner warned people not to travel unless absolutely necessary.
According to Lindner, “There may be a break in the activity in the afternoon hours before another complex of storms arrives overnight into Friday morning with additional heavy rainfall. But confidence in the forecast is not high.”
Impact of Rains
“Significant rainfall has also occurred over the headwaters of the East Fork of the San Jacinto River. New flood waves will certainly be generated on both the East and West Forks of the San Jacinto River,” Lindner added. The same holds true for Lake Livingston and the Trinity River.
The heavy runoff over already saturated grounds will migrate downstream Friday into the weekend.
The SJRA does not have a dam on the East Fork and can’t control it. Dam releases on the West Fork do not impact the East Fork, but do impact Lake Houston.
Lake Conroe Release Rate Increasing, Max Uncertain
Lake Conroe virtually quadrupled its release rate from 17,000 cubic feet per second (CFS) at 7 AM to 60,455 CFS at 9:45 AM.
The lake level at 10:48 AM had reached 204.4 – 3.4 feet above normal.
Mark Micheletti, San Jacinto River Authority (SJRA) board member, said that SJRA engineers are modeling several release scenarios. So the ultimate release rate is uncertain as of this writing.
The flowage easement at Lake Conroe is 207. That’s the elevation at which homes start to flood.
Some people will criticize the SJRA for not releasing more water sooner. However, it was not an easy call.
Lake Houston was already flooding from the East Fork. And a massive release coming down the West Fork could have flooded homes.
Micheletti added, “Hydrographs are useless in a situation like this because you don’t yet know what the release will be,” he added.
During Harvey, the SJRA released 79,000 CFS. So, they are already at 75 percent of the devastating Harvey release rate.
But even with that, the current release rate is only about one third of the estimated water coming into the lake. “So that’s our challenge,” said Micheletti. The release rate will almost certainly go higher.”
The Harris County Flood Warning system showed that the San Jacinto West Fork is still within banks, but that likely won’t last long.
Before the heavy rains moved south this morning, river gages on the East and West Forks were dropping slowly as floodwaters receded from earlier in the week. But we’re about to experience a second wave there.
If you’re in a place that has flooded before, the safest course of action is to start developing an action plan now.
River Predictions
At 10 AM, Lindner released new hydrographs for the West Fork, East Fork, and the area below Lake Houston.
West Fork
As of 10 AM, 5.2.24
A rise to flood stage will occur today with a rise above major flood levels on Friday. Widespread low land flooding near the river is expected. The forecast may need to be increased more because of the uncertainty over Lake Conroe releases.
While there will be widespread low land flooding, the lowest structures in Kingwood are not impacted until over 60-62ft. Expect this level of water in the river to create backwater in tributaries that could lead to additional flooding.
A reader sent in this photo of the new Northpark South development between the West Fork and Sorters-McClellan Road.
NorthPark South already underwater from rains. 5.2.24 at 11 AM. Photo by Jody Binnion.
East Fork
A significant rise on the East Fork is expected as the upstream flood wave moves downstream. Forecasted water levels will reach 6-8 ft higher than earlier this week. This expected flood level will be higher than TS Imelda and will be similar to October 1994. Even elevated structures may be flooded, according to Lindner.
Below Lake Houston
Other Flooding
As I write this, I have received word that Taylor Gully is flooding and parts of nearby streets are closed.
White Oak Creek is also flooding. Royal Pines, the new development on White Oak at the northern end of West Lake Houston Parkway, has also flooded neighbors’ yards and a garage.
Flash flooding is ongoing along Willow and Spring Creeks, which are rising rapidly. Flooding along these creeks is becoming likely. Widespread street flooding and some structure flooding is possible.
A training band of thunderstorms will produce another 2-4 inches of rainfall on top of the already 4-6 inches that has fallen in these watersheds.
Pardon the pun, but the situation is very fluid. Sometimes new information comes in faster than I can update it.
I will post updates including photos when the rain lets up.
Posted by Bob Rehak at 10:00 AM on 5/2/24
2438 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2024/05/image001-2.png?fit=892%2C697&ssl=1697892adminadmin2024-05-02 10:54:252024-05-02 11:51:31Lake Conroe Increasing Release Rate After Torrential Rain
May 1, 2024 – Even as East Fork homes are flooding, the National Weather Service has issued another Flood Watch for the region.
Monday’s Storm Brings Wednesday’s Flood
The stormwater from last Sunday night/Monday morning that’s flooding homes near the East Fork San Jacinto could get reinforcements tonight. Another powerful storm is approaching and will collide with moisture laden air from the Gulf later day.
That caused the National Weather Service to issue another flood watch from 10 PM this evening until Thursday evening for Houston and Harris County.
That same NWS bulletin also says that a flood warning remains in effect for the East Fork San Jacinto near New Caney affecting Liberty, Montgomery and Harris Counties.
Jeff Lindner, Harris County’s meteorologist, warned in his midday report that “Widespread amounts of 2-5 inches are likely with isolated totals of 6-9 inches. High hourly rainfall rates will be likely on the order of 2-4 inches which will produce rapid onset flash flooding.”
Lake Conroe and Lake Livingston Already Taxed to Max
The additional rainfall could overburden already overtaxed watersheds. “There is no capacity at either Lake Livingston or Lake Conroe,” said Lindner. “Additional inflows and run-off will have to pass through the dams’ floodgates.”
Although Lindner expects the heaviest rains to stay north of Harris County, “There is some potential that some of the heavy rainfall reaches into northern Harris County overnight,” he added.
If so, the storm could impact Spring, Cypress, Little Cypress, and Willow Creeks as well as the tributaries in northern Waller and southwestern Montgomery Counties, such as Lake Creek.
Lindner says significant rises will be possible depending on the rainfall amounts and patterns. Flash flooding will be likely where heavy rains occur.
That could deal a devastating blow to homes already flooding along the East Fork.
East Fork Photos Taken Morning of Mayday Flood
Pictures taken this morning between 9 and noon showed roads flooded out and many homes and vehicles already underwater.
TXDoT closed FM1485 at the East Fork/Montgomery County line.SH99 on left, FM1485 on right.
Streets close to the river also flooded.
Looking S. Casey Road on left flooding from East Fork on right.Home with flooded vehicles and heavy equipment at Casey and Spaulding.Flooded homes at Casey and Green. Cypress Hollow just N of SH99.
I took more than a hundred photos like these this morning. Some people were lucky with the water stopping just feet from their homes. Other people were not so lucky. They will need help.
Colony Ridge, Plum Grove and FM2090
Farther north, I explored Colony Ridge and Plum Grove near FM2090.
One of the main entrances to Colony Ridgewhere it approaches Plum Grove Road
The water there was already starting to recede. But still, many roads were barely passable. Most smaller vehicles did not brave the water.
Opposite angle, same intersection. Unable to see the sides of the road, traffic tried to stay close to the centerline to stay out of the ditches.Looking NW over East Fork. FM2090 was still passable, but water lapped at the bottom of the bridge. The East Fork completely flooded the abandoned sand mine (upper right) and swept sediment out of mine.
Ironically, even though I could see my way out of Colony Ridge (from the air), I could not get to FM2090 on the ground because of floodwaters. I had to drive south to SH99 to return home.
Dunnam Road Boat Launch
Back in Kingwood, I called a friend on Dunnam Road. She said her boat launch flooded and that water was lapping at the first house coming up the hill.
Dunnam Road boat launch.Note water surrounding house adjacent to boat dock. Luckily it did not flood and water is receding as of 4PM.This young man appeared to be making the most of the flood by giving his daughter a fishing lesson.A neighbor told me he’s been doing that since she was born!
Posted by Bob Rehak on May 1, 2024
2437 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2024/05/20240501-DJI_20240501090820_0035_D.jpg?fit=1100%2C619&ssl=16191100adminadmin2024-05-01 16:35:032024-05-01 16:35:05East Fork Homes Flooding, Another Flood Watch Issued
(Updated with more Subdivisions/Streets at 9PM Tuesday) As yesterday’s heavy rains work their way downstream, the National Weather Service’s (NWS) Advanced Hydrologic Prediction Service forecasts that the East Fork at FM1485 will rise 15 feet in the next 24 hours.
As of noon Tuesday, NWS said the river had already reached the “Action Stage” at 56.85 feet. NWS predicts it will reach 71.9 feet by tomorrow at noon. “Major flooding” at that location begins at 69 feet.
Jeff Lindner, Harris County’s meteorologist, says, “Many of the structures in this area have been elevated, however isolated homes that remain on the ground will be subject to flooding at these levels.”
FM1485 will be under several feet of water. Flows may even approach the deck of the Highway 99 bridge!
Subdivisions and Streets that Could Be Affected
Lindner specifically warned about flooding that could affect the following subdivisions and streets.
Magnolia Point (West end of Commons of Lake Houston)
Opal Way
Diamond
Mendencino
Lassen Villa
Glen
Magnolia
Hill
Calvins
Collins
Calaveras Creek
Flooding of streets is likely. Elevated homes will be cut-offSome structure flooding is possible for any homes on the ground in this area.
South of FM 1485 (east side of the river):
Spalding
Green
Jett
Casey
Some structure flooding is possible for any homes on the ground in this area.
Idle Glen subdivision:
Brookside
Chinquapin
River Side
E. San Jacinto
Glenwood
Dipping
Idlewild
Lazy Creek
Almost all of the homes in this area are elevated, but will be cut-off. Any homes on the ground will be flooded.
Northwood Country Estates:
Flooding of streets is likely. Elevated homes will be cut-off.
Disher
Bounds
Thomas
Davidson
A new 553-acre Friendswood development called Sila is in this area.
River Terrace:
Flooding of the following streets is likely. Elevated homes will be cut-off.
River Terrace
Elm
Pine
Cherry Laurel
Holly
Cypress
Cypress Point:
The following streets will be flooded (closest to the river). Elevated homes will be cut-off.
Blue Lake
Oak Knoll
Wild Oak
Birchwood
The East Fork should also rise 10-15 feet at FM2090.
East Fork at Cleveland
Farther upstream at Cleveland, the East Fork has already peaked and is beginning to recede after only reaching a moderate level of flooding.
As of noon 4/30/24, the East Fork at Cleveland was at a moderate flood stage.
Structure Flooding In Kingwood NOT Expected
Lindner added that, “Flooding will occur in the low lying areas of Kingwood that back up to the East Fork of the San Jacinto River. This is mostly all non-developed lands near the river or back yards with bulkhead that front the river. Structure flooding is NOT expected in Kingwood.”
Meanwhile, at as of noon on 4/30/24, NWS predicts the West Fork will not flood.
Noon, 4/30/24
View Real-Time Inundation Mapping
To view Real-Time Inundation Mapping, go to www.harriscountyfws.org and click “inundation map” on the left side.
Trinity River Also Flooding Badly
The Trinity River at Liberty is about to see major flooding through Sunday. The Trinity is a separate watershed. It will not affect Harris County.
As of noon, 4/30/2024
Other Flooding
Fourteen gages show various streams and creeks in the region are at or near flood stage.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2024/04/EastForkat1485.png?fit=600%2C465&ssl=1465600adminadmin2024-04-30 14:02:482024-04-30 21:28:23East Fork Predicted to Rise 15 Feet in Next 24 Hours
Lake Conroe Increasing Release Rate After Torrential Rain
5/2/24 Noon Update: Since publishing this, Lake Conroe has continued to rise and the SJRA has increased the release rate to 66,100 CFS. – Heavy storms dumped 10-12 inches of rain in isolated areas north of Lake Conroe last night. Most areas experienced 5-7 inches. As a result, Lake Conroe has increased its release rate to 60,455 cubic feet per second and it could go higher.
The area north of Lake Conroe has received more than 17 inches in the last week.
Engineers are currently modeling several different scenarios. The current inflow is more than two times greater than the outflow. The current release rate is already the second highest in the history of Lake Conroe.
Current Situation
According to Jeff Lindner, Harris County meteorologist, significant flash flooding is ongoing from north of HWY 105 to southern Montgomery County and the northern portions of Harris County.
At 8:27 am, radar showed the storm had moved into northern Harris, and northern Liberty Counties.
It dumped 6 inches of rain in my gauge in two hours. And the total is still climbing.
Such high hourly rainfall rates result in street flooding. Lindner warned people not to travel unless absolutely necessary.
According to Lindner, “There may be a break in the activity in the afternoon hours before another complex of storms arrives overnight into Friday morning with additional heavy rainfall. But confidence in the forecast is not high.”
Impact of Rains
“Significant rainfall has also occurred over the headwaters of the East Fork of the San Jacinto River. New flood waves will certainly be generated on both the East and West Forks of the San Jacinto River,” Lindner added. The same holds true for Lake Livingston and the Trinity River.
The heavy runoff over already saturated grounds will migrate downstream Friday into the weekend.
The SJRA does not have a dam on the East Fork and can’t control it. Dam releases on the West Fork do not impact the East Fork, but do impact Lake Houston.
Lake Conroe Release Rate Increasing, Max Uncertain
Lake Conroe virtually quadrupled its release rate from 17,000 cubic feet per second (CFS) at 7 AM to 60,455 CFS at 9:45 AM.
The lake level at 10:48 AM had reached 204.4 – 3.4 feet above normal.
Mark Micheletti, San Jacinto River Authority (SJRA) board member, said that SJRA engineers are modeling several release scenarios. So the ultimate release rate is uncertain as of this writing.
The flowage easement at Lake Conroe is 207. That’s the elevation at which homes start to flood.
Some people will criticize the SJRA for not releasing more water sooner. However, it was not an easy call.
Lake Houston was already flooding from the East Fork. And a massive release coming down the West Fork could have flooded homes.
Micheletti added, “Hydrographs are useless in a situation like this because you don’t yet know what the release will be,” he added.
During Harvey, the SJRA released 79,000 CFS. So, they are already at 75 percent of the devastating Harvey release rate.
But even with that, the current release rate is only about one third of the estimated water coming into the lake. “So that’s our challenge,” said Micheletti. The release rate will almost certainly go higher.”
The Harris County Flood Warning system showed that the San Jacinto West Fork is still within banks, but that likely won’t last long.
Before the heavy rains moved south this morning, river gages on the East and West Forks were dropping slowly as floodwaters receded from earlier in the week. But we’re about to experience a second wave there.
If you’re in a place that has flooded before, the safest course of action is to start developing an action plan now.
River Predictions
At 10 AM, Lindner released new hydrographs for the West Fork, East Fork, and the area below Lake Houston.
West Fork
A rise to flood stage will occur today with a rise above major flood levels on Friday. Widespread low land flooding near the river is expected. The forecast may need to be increased more because of the uncertainty over Lake Conroe releases.
While there will be widespread low land flooding, the lowest structures in Kingwood are not impacted until over 60-62ft. Expect this level of water in the river to create backwater in tributaries that could lead to additional flooding.
A reader sent in this photo of the new Northpark South development between the West Fork and Sorters-McClellan Road.
East Fork
A significant rise on the East Fork is expected as the upstream flood wave moves downstream. Forecasted water levels will reach 6-8 ft higher than earlier this week. This expected flood level will be higher than TS Imelda and will be similar to October 1994. Even elevated structures may be flooded, according to Lindner.
Below Lake Houston
Other Flooding
As I write this, I have received word that Taylor Gully is flooding and parts of nearby streets are closed.
White Oak Creek is also flooding. Royal Pines, the new development on White Oak at the northern end of West Lake Houston Parkway, has also flooded neighbors’ yards and a garage.
Flash flooding is ongoing along Willow and Spring Creeks, which are rising rapidly. Flooding along these creeks is becoming likely. Widespread street flooding and some structure flooding is possible.
A training band of thunderstorms will produce another 2-4 inches of rainfall on top of the already 4-6 inches that has fallen in these watersheds.
Pardon the pun, but the situation is very fluid. Sometimes new information comes in faster than I can update it.
I will post updates including photos when the rain lets up.
Posted by Bob Rehak at 10:00 AM on 5/2/24
2438 Days since Hurricane Harvey
East Fork Homes Flooding, Another Flood Watch Issued
May 1, 2024 – Even as East Fork homes are flooding, the National Weather Service has issued another Flood Watch for the region.
Monday’s Storm Brings Wednesday’s Flood
The stormwater from last Sunday night/Monday morning that’s flooding homes near the East Fork San Jacinto could get reinforcements tonight. Another powerful storm is approaching and will collide with moisture laden air from the Gulf later day.
That caused the National Weather Service to issue another flood watch from 10 PM this evening until Thursday evening for Houston and Harris County.
That same NWS bulletin also says that a flood warning remains in effect for the East Fork San Jacinto near New Caney affecting Liberty, Montgomery and Harris Counties.
Jeff Lindner, Harris County’s meteorologist, warned in his midday report that “Widespread amounts of 2-5 inches are likely with isolated totals of 6-9 inches. High hourly rainfall rates will be likely on the order of 2-4 inches which will produce rapid onset flash flooding.”
Lake Conroe and Lake Livingston Already Taxed to Max
The additional rainfall could overburden already overtaxed watersheds. “There is no capacity at either Lake Livingston or Lake Conroe,” said Lindner. “Additional inflows and run-off will have to pass through the dams’ floodgates.”
Although Lindner expects the heaviest rains to stay north of Harris County, “There is some potential that some of the heavy rainfall reaches into northern Harris County overnight,” he added.
If so, the storm could impact Spring, Cypress, Little Cypress, and Willow Creeks as well as the tributaries in northern Waller and southwestern Montgomery Counties, such as Lake Creek.
Lindner says significant rises will be possible depending on the rainfall amounts and patterns. Flash flooding will be likely where heavy rains occur.
That could deal a devastating blow to homes already flooding along the East Fork.
East Fork Photos Taken Morning of Mayday Flood
Pictures taken this morning between 9 and noon showed roads flooded out and many homes and vehicles already underwater.
Streets close to the river also flooded.
I took more than a hundred photos like these this morning. Some people were lucky with the water stopping just feet from their homes. Other people were not so lucky. They will need help.
Colony Ridge, Plum Grove and FM2090
Farther north, I explored Colony Ridge and Plum Grove near FM2090.
The water there was already starting to recede. But still, many roads were barely passable. Most smaller vehicles did not brave the water.
Ironically, even though I could see my way out of Colony Ridge (from the air), I could not get to FM2090 on the ground because of floodwaters. I had to drive south to SH99 to return home.
Dunnam Road Boat Launch
Back in Kingwood, I called a friend on Dunnam Road. She said her boat launch flooded and that water was lapping at the first house coming up the hill.
Posted by Bob Rehak on May 1, 2024
2437 Days since Hurricane Harvey
East Fork Predicted to Rise 15 Feet in Next 24 Hours
(Updated with more Subdivisions/Streets at 9PM Tuesday) As yesterday’s heavy rains work their way downstream, the National Weather Service’s (NWS) Advanced Hydrologic Prediction Service forecasts that the East Fork at FM1485 will rise 15 feet in the next 24 hours.
As of noon Tuesday, NWS said the river had already reached the “Action Stage” at 56.85 feet. NWS predicts it will reach 71.9 feet by tomorrow at noon. “Major flooding” at that location begins at 69 feet.
Jeff Lindner, Harris County’s meteorologist, says, “Many of the structures in this area have been elevated, however isolated homes that remain on the ground will be subject to flooding at these levels.”
FM1485 will be under several feet of water. Flows may even approach the deck of the Highway 99 bridge!
Subdivisions and Streets that Could Be Affected
Lindner specifically warned about flooding that could affect the following subdivisions and streets.
Magnolia Point (West end of Commons of Lake Houston)
Flooding of streets is likely. Elevated homes will be cut-offSome structure flooding is possible for any homes on the ground in this area.
South of FM 1485 (east side of the river):
Some structure flooding is possible for any homes on the ground in this area.
Idle Glen subdivision:
Almost all of the homes in this area are elevated, but will be cut-off. Any homes on the ground will be flooded.
Northwood Country Estates:
River Terrace:
Cypress Point:
The East Fork should also rise 10-15 feet at FM2090.
East Fork at Cleveland
Farther upstream at Cleveland, the East Fork has already peaked and is beginning to recede after only reaching a moderate level of flooding.
Structure Flooding In Kingwood NOT Expected
Lindner added that, “Flooding will occur in the low lying areas of Kingwood that back up to the East Fork of the San Jacinto River. This is mostly all non-developed lands near the river or back yards with bulkhead that front the river. Structure flooding is NOT expected in Kingwood.”
Meanwhile, at as of noon on 4/30/24, NWS predicts the West Fork will not flood.
View Real-Time Inundation Mapping
To view Real-Time Inundation Mapping, go to www.harriscountyfws.org and click “inundation map” on the left side.
Trinity River Also Flooding Badly
The Trinity River at Liberty is about to see major flooding through Sunday. The Trinity is a separate watershed. It will not affect Harris County.
Other Flooding
Fourteen gages show various streams and creeks in the region are at or near flood stage.
To see gage levels and predictions for a stream near you, go to the NWS Advanced Hydrologic Prediction Service.
The Harris County Flood Warning System offers many of the same features plus more, such as historical flood heights.
Posted by Bob Rehak on 4/30/24 at 2PM
2436 Days since Hurricane Harvey