City of Houston Mayor Pro Tem Dave Martin announced this afternoon that the Texas Department of Transportation (TxDOT) will close the intersection of Kingwood Drive and Texas Loop 494 this weekend. The closure starts Friday evening, April 17 and, weather permitting, will last through early Monday morning, April 20.
Purpose of Closure
This is a bit off topic for a flood blog, but Kingwood Drive affects half my readers and 494 affects many more. Here’s what’s happening.
TxDOT will raise the intersection of Kingwood Drive and 494 with two feet of asphalt. The purpose: to remove the dip by the UP railroad tracks.
Weather permitting, construction should start at 9:00 p.m. on Friday. Crews will work continuously until 5:00 a.m. Monday.
Please watch for flagmen and orange traffic cones indicating detours. Detours at Crescent Springs, Butterfly Lane, Royal Forest and Northpark Drive are shown below.
For more information, contact TxDOT at (936) 538-3300.
Posted by Bob Rehak on 4/15/2020
960 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/04/IMG_0003.png?fit=1200%2C800&ssl=18001200adminadmin2020-04-15 15:49:002020-04-15 17:14:31Kingwood Drive and Loop 494 Intersection Closed This Weekend
After the Easter weekend, the San Jacinto River Authority (SJRA) started its seasonal-release plan. The river authority is currently releasing at a rate of 529 cubic feet per second (CFS) from Lake Conroe. At that rate, the lake should reach its target level of 200 feet above sea level by the end of April, according to Jace Houston, general manager of the SJRA.
SJRA Seasonal Release on 4/15/2020. One tainter gate open six inches releases a slow, steady stream of 529 cfs. Image courtesy of SJRA.
The slow rate of release avoids flooding downstream property and the lower lake level provides additional capacity in the lake. That additional capacity provides a buffer against flooding for downstream residents.
About Seasonal Lake Lowering Policy
Houston said the River Authority will hold the lake at 200 feet through the end of May, then allow it to reach its normal level for most of the summer.
Lake Conroe actually reached 200.75 feet before SJRA began its seasonal lowering this week.A reduction of .14 feet equates to about one and two-thirds inches of lowering so far.
At 200.75 feet, Lake Conroe was actually above its highest average monthly level for the year, which is 200.44 feet in May. The normal level for April is 200.32 feet.
Lake Conroe seasonal levels by month. From SJRA board presentation by Chuck Gilman in January.
Earlier this year, a bitter fight broke out between upstream and downstream property owners over the seasonal lake lowering policy. The SJRA board decided to extend the lake lowering plan, but modify it. In the fall, they will let the City of Houston, which owns two-thirds of the water in the lake, decide whether to take the lake down below 199.5 feet.
Despite the start of the seasonal release and last week’s rains, the level of Lake Houston has declined this week. And rivers are far from flooding.
Normal level for Lake Houston is 42.5 feet, but City is still lowering lake for spillway maintenance.
Uncertain Weather for This Weekend
Jeff Lindner, Harris County meteorologist, predicts that storms this weekend could bring several inches of rain. “With the Gulf of Mexico water temperatures running several degrees above average for this time of year, winds blowing off the Gulf will need little time to supply a rich moisture-laden air mass.”
The NWS predicts a 30-40% chance of showers and thunderstorms for this weekend as a front passes. However, Lindner notes, models diverge widely in their predictions. The Global Forecast System (GFS model) predicts that most rain will happen over the Gulf with little impact to land.
However, the European Medium Range Forecast Model (ECMWF) predicts a very wet weekend with several rounds of storms and several inches of rainfall for much of southeast Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/02/20200220-RJR_8690.jpg?fit=800%2C1200&ssl=11200800adminadmin2020-04-15 13:26:562020-04-15 20:58:42SJRA Starts Seasonal Release to Lower Lake Conroe
The developer says he purchased 110 acres. He will reserve 20 acres of that (18%) for detention. The remaining 90 acres, he says, are all above the 500-year floodplain. The lowest part of the property sits at 50 feet above sea level. That’s 7.5 feet above the average level of Lake Houston. However, he says the highest properties, those closest to Kingwood Drive, are at 90 feet.
Possible names for the development include Kingwood Heights and Holley Heights, to help offset the fear of flooding and communicate the location above the current 500 year floodplain.
Holley says he conducted environmental, wetland, and tree surveys on the property in the last year. He wants to preserve as many trees as possible. Lot sizes will range from half- to 1+ acres.
USGS Shows No Wetlands Issues for Property
USGS shows no wetlands on the Kingwood Cove Golf Course, though it does show two ponds.
FEMA Shows Narrow 500-year Flood Zone
In the map below, the cross-hatched area represents the floodway. The aqua colored area represents the 100-year floodplain and the brown area the 500-year floodplain. The narrowness of the 500-year band indicates a steep slope. In fact, the land rises sharply from a low river terrace to a higher terrace in that transition zone.
FEMA’s National Flood Hazard Layer View shows only the extreme lower portion of the course in flood hazard areas.
Timing of Development
Holley says people could start building homes on the old course early next year. However, he did not say whether the property was permitted yet.
Other local subdivisions developed by Holley include: Kings Harbor, Deer Ridge Estates, Kings Lake Estates, and Summer Lake Ranch. Holley has developed land in the Kingwood area since 1992.
Is Drainage Sufficient?
Mr. Holley did say that 41 Forest Cove homeowners flooded during Imelda last year. Based on their concerns, he said that he is increasing drainage. He declined to answer other questions until he gets “further along in the engineering.”
Many neighbors have expressed concerns about the loss of pervious cover to streets, driveways, rooftops, etc. If the land is going to be developed, low density makes the most sense. And one or two families per acre certainly is better than four to eight. We have seen many such higher-density developments upstream in Montgomery County. Take Northpark Woods, for instance. Many Montgomery County developments do not even require detention ponds.
This project resides both within the City of Houston and Harris County. I will continue to watch it as the engineering evolves.
Detention in Floodways Less Effective
About 4 acres of the 20 acres on the lower terrace sits in the floodway. One flood expert told me, “Generally, detention basins in the floodway aren’t as effective (compared to those in a floodplain) because they get full of water before they can be of much use during a flood event. A detention basin works where it can fill up and store water during a major flood event, basically an extension of the natural floodplain.”
Posted by Bob Rehak on 4/14/2020
959 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/04/Kingwood-Cove-Flood-Zones.jpg?fit=1200%2C918&ssl=19181200adminadmin2020-04-14 17:05:512020-04-14 17:18:41Ron Holley Describes His Vision for Forest Cove Golf-Course Development
Kingwood Drive and Loop 494 Intersection Closed This Weekend
City of Houston Mayor Pro Tem Dave Martin announced this afternoon that the Texas Department of Transportation (TxDOT) will close the intersection of Kingwood Drive and Texas Loop 494 this weekend. The closure starts Friday evening, April 17 and, weather permitting, will last through early Monday morning, April 20.
Purpose of Closure
This is a bit off topic for a flood blog, but Kingwood Drive affects half my readers and 494 affects many more. Here’s what’s happening.
TxDOT will raise the intersection of Kingwood Drive and 494 with two feet of asphalt. The purpose: to remove the dip by the UP railroad tracks.
Please watch for flagmen and orange traffic cones indicating detours. Detours at Crescent Springs, Butterfly Lane, Royal Forest and Northpark Drive are shown below.
For more information, contact TxDOT at (936) 538-3300.
Posted by Bob Rehak on 4/15/2020
960 Days since Hurricane Harvey
SJRA Starts Seasonal Release to Lower Lake Conroe
After the Easter weekend, the San Jacinto River Authority (SJRA) started its seasonal-release plan. The river authority is currently releasing at a rate of 529 cubic feet per second (CFS) from Lake Conroe. At that rate, the lake should reach its target level of 200 feet above sea level by the end of April, according to Jace Houston, general manager of the SJRA.
About Seasonal Lake Lowering Policy
Houston said the River Authority will hold the lake at 200 feet through the end of May, then allow it to reach its normal level for most of the summer.
At 200.75 feet, Lake Conroe was actually above its highest average monthly level for the year, which is 200.44 feet in May. The normal level for April is 200.32 feet.
Earlier this year, a bitter fight broke out between upstream and downstream property owners over the seasonal lake lowering policy. The SJRA board decided to extend the lake lowering plan, but modify it. In the fall, they will let the City of Houston, which owns two-thirds of the water in the lake, decide whether to take the lake down below 199.5 feet.
The extra lowering in the fall helps protect against hurricanes and tropical storms, such as Harvey and Imelda. The SJRA begins slowly lowering the lake in August for the peak of hurricane season in September and then letting it resume its normal level again in October. For the exact details of the policy adopted by the board in its February meeting, click here.
Lake Houston Level Declining
Despite the start of the seasonal release and last week’s rains, the level of Lake Houston has declined this week. And rivers are far from flooding.
Uncertain Weather for This Weekend
Jeff Lindner, Harris County meteorologist, predicts that storms this weekend could bring several inches of rain. “With the Gulf of Mexico water temperatures running several degrees above average for this time of year, winds blowing off the Gulf will need little time to supply a rich moisture-laden air mass.”
The NWS predicts a 30-40% chance of showers and thunderstorms for this weekend as a front passes. However, Lindner notes, models diverge widely in their predictions. The Global Forecast System (GFS model) predicts that most rain will happen over the Gulf with little impact to land.
Which Model is Better?
ECMWF is considered one of the premiere global forecasting models for the mid-latitudes. Statistically, it has been more accurate than the GFS model.
NOAA has tripled spending on supercomputing capacity to make GFS the best model in the world again.
Posted by Bob Rehak on 4/15/2020
960 Days after Hurricane Harvey
Ron Holley Describes His Vision for Forest Cove Golf-Course Development
In April 2019, Ron Holley, a major Kingwood developer, bought the Kingwood Cove Golf Course. Neighbors immediately started asking questions about how his plans could affect potential flooding. Forty-one Forest Cove residents flooded during Imelda last year. On 4/12 this year, Holley shared his vision for the property in a KPRC radio interview.
Description of Development
The developer says he purchased 110 acres. He will reserve 20 acres of that (18%) for detention. The remaining 90 acres, he says, are all above the 500-year floodplain. The lowest part of the property sits at 50 feet above sea level. That’s 7.5 feet above the average level of Lake Houston. However, he says the highest properties, those closest to Kingwood Drive, are at 90 feet.
Possible names for the development include Kingwood Heights and Holley Heights, to help offset the fear of flooding and communicate the location above the current 500 year floodplain.
Holley says he conducted environmental, wetland, and tree surveys on the property in the last year. He wants to preserve as many trees as possible. Lot sizes will range from half- to 1+ acres.
USGS Shows No Wetlands Issues for Property
FEMA Shows Narrow 500-year Flood Zone
In the map below, the cross-hatched area represents the floodway. The aqua colored area represents the 100-year floodplain and the brown area the 500-year floodplain. The narrowness of the 500-year band indicates a steep slope. In fact, the land rises sharply from a low river terrace to a higher terrace in that transition zone.
Timing of Development
Holley says people could start building homes on the old course early next year. However, he did not say whether the property was permitted yet.
Other local subdivisions developed by Holley include: Kings Harbor, Deer Ridge Estates, Kings Lake Estates, and Summer Lake Ranch. Holley has developed land in the Kingwood area since 1992.
Is Drainage Sufficient?
Mr. Holley did say that 41 Forest Cove homeowners flooded during Imelda last year. Based on their concerns, he said that he is increasing drainage. He declined to answer other questions until he gets “further along in the engineering.”
Many neighbors have expressed concerns about the loss of pervious cover to streets, driveways, rooftops, etc. If the land is going to be developed, low density makes the most sense. And one or two families per acre certainly is better than four to eight. We have seen many such higher-density developments upstream in Montgomery County. Take Northpark Woods, for instance. Many Montgomery County developments do not even require detention ponds.
This project resides both within the City of Houston and Harris County. I will continue to watch it as the engineering evolves.
Detention in Floodways Less Effective
About 4 acres of the 20 acres on the lower terrace sits in the floodway. One flood expert told me, “Generally, detention basins in the floodway aren’t as effective (compared to those in a floodplain) because they get full of water before they can be of much use during a flood event. A detention basin works where it can fill up and store water during a major flood event, basically an extension of the natural floodplain.”
Posted by Bob Rehak on 4/14/2020
959 Days since Hurricane Harvey