This is a bit off topic for a flood blog, but it affects tens of thousands of readers. Late yesterday, after multiple heat records were broken across the region, the City of Houston announced water-use restrictions going into effect Sunday, August 27, 2023. Let me address the heat first, water restrictions second. Then I’ll discuss rain chances and the tropics.
Heat Records Shattered Across Houston Region
Yesterday, the Houston area experienced another unrelenting afternoon of scorching temperatures. Many areas reached the mid- to upper-100’s with a few areas into the low 110’s.
Afternoon daily temperature records were shattered at many sites – many by several degrees.
Jeff Lindner, Harris County Meteorologist
High Temperatures on Thursday, 8/24/23
BUSH IAH: 109 (tied the all time record high, broke daily record high of 105 from 1980)
Huntsville: 111 (shattered record high of 102 from 2011…daily record high broken by 9 degrees)
College Station: 111 (broke record high of 107 from 2010)
Hobby: 107 (broke record high of 100 from 1980)
Conroe: 108 (broke record high of 105 from 1922…101 year old record)
Brenham: 107 (broke record high of 106 from 1980)
Sugar Land: 107 (broke record high of 101 from 2011)
Wharton: 106 (shattered the record high of 99 from 1911…112 year old record)
Cleveland: 109 (broke record high of 104 from 1980)
Crockett: 109 (broke record high of 106 from 2011)
CoH Water-Use Restrictions
According to a City of Houston press release, Houston has entered Stage Two of the City’s Drought Contingency Plan. Due to intense heat and a significant drop in annual rainfall. Effective August 27, 2023, mandatory water-use restrictions will go into effect. They apply to the entire City:
Limit outdoor watering to twice a week between the hours of 7PM and 5AM
Sundays and Thursdays for single-family residential customers with even-numbered addresses
Saturdays and Wednesdays for single-family residential customers with odd-numbered addresses
Tuesdays and Fridays for all other customers
Any outdoor water use that results in city water leaving your property (i.e., draining onto adjacent property, or streets or gutters) is unlawful.
Violations of watering times will get you a written warning for the first violation. Any subsequent violations are subject to a fine up to $2,000 for each occurrence; see Section 54.001 of the Texas Local Government Code.
Easy Ways to Conserve Water
Here are some easy ways to conserve water:
Check and repair water leaks, including dripping faucets and running toilets.
Check sprinkler heads to make sure water is not spraying into the street or directly into a storm drain and/or gutters.
Avoid washing sidewalks, patio furniture or cars. If you must wash your car, use a car wash. Most car washes use recycled water.
Run dishwashers and clothes washers only when full.
Take shorter showers.
Install a rain barrel and use it for outdoor watering.
Turn off the water when you are not using it (e.g., while brushing teeth or shaving).
For more water-saving tips, visit www.givewaterabreak.org.
Rain Chances
The high-pressure ridge parked over us for the last two months is giving a little bit of ground. Yesterday, thunderstorms finally overcame subsidence in the super-heated afternoon air mass. The gage at the West Lake Houston Parkway bridge recorded 0.44 inches of rain. Despite several downed trees, people cheered because of our deep drought.
According to Jeff Lindner, Harris County Meteorologist, as high pressure moves west, weak disturbances may approach the area from the east and northeast.
Combined with high temperatures in the low- to mid-100’s, scattered thunderstorms will be possible.
Wildfire Risk Remains
Thunderstorms come with the threat for lightning-induced wildfires. One such fire started yesterday in the Humble area. Lightning strikes will be possible each day and strong gusty winds can quickly fan fires.
Additionally, wind direction and speeds can quickly change near and around thunderstorms creating very hazardous conditions for ground crews. Multiple fires caused by a single thunderstorm can quickly overwhelm local resources. So use extra caution. Burn bans remain in effect.
Western Caribbean Sea
An area of low pressure has crossed Central America into the western Caribbean Sea. It should move north toward Florida. As of this morning, the National Hurricane Center gave it a 70% chance of formation during the next 7 days.
However, it remains unclear where exactly any surface low will form and how it may interact with the surrounding landmasses. Additionally, there may be wind shear to contend with in the southeastern Gulf of Mexico. At this time, models predict varying intensity as the storm moves north.
Currently, this system does not pose a threat to Texas. But watch for winds that could enhance our local fire weather.
Posted by Bob Rehak on 8/25/2023based on information from Jeff Lindner, Harris County Meteorologist, and City of Houston
2187 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/08/two_atl_7d0-4.png?fit=900%2C665&ssl=1665900adminadmin2023-08-25 11:14:582023-08-25 11:24:44Heat Records and Water-Use Restrictions
By Jeff Lindner, Harris County Flood Control District’s Director Hydrologic Operations Division/Meteorologist, with a few minor edits for a non-technical audience.
There have been many comparisons of this summer to that of 2011 with respect to the heat and drought. Below, see the comparison of drought, water supply storage, and heat between 2011 and 2023.
Rainfall (Jan 1 to Aug 23)
2023 Rainfall
2023 Departure
2011 Rainfall
2011 Departure
BUSH IAH
29.97
-2.29
10.93
-21.33
Hobby
22.20
-11.83
10.47
-23.56
Conroe
28.41
-3.25
17.54
-14.69
College Station
21.47
-3.79
10.57
-14.12
As the table above shows, the rainfall departures in 2011 were significantly greater at all sites. That indicates a much more significant drought in 2011 than in 2023.
Rainfall departures in 2023 were tempered by a wet April and May over much of the area, while in 2011 drought conditions in the spring were some of the worst ever recorded with many areas recording their driest spring ever. 2011 was also preceded by dryness in late 2010 that helped to worsen the 2011 drought conditions and water supply concerns.
Rainfall at Hobby Airport in 2011 (Feb-May) was only 1.31 inches compared to 2023 of 11.85 inches.
While it is clear that 2011 was worse with respect to lack of rainfall, the abrupt change in rainfall from late spring into the summer of 2023 has “shocked” vegetation across the region.
Additionally, it has been hotter to some degree (especially overnight) in 2023 and the flash drought has been severe with nearly the entire area drought free in early June to all of the area in severe to extreme drought as of August 15th.
The very warm maximum temperatures and record “high” low temperatures over the region have resulted in rapid degradation of vegetation health. Tree losses were staggering in 2011 and the area is starting to see losses mounting in 2023, but far below what was experienced at this point in 2011.
Comparison of Drought Conditions, Extents
In 2011, exceptional drought covered most of the state.
In 2023, exceptional drought is minuscule by comparison.
Reservoir Storage
2011 also featured significant drawdown on area lakes and water supply reservoirs as the longer duration “hydrological” drought resulted in record or near record low inflows to several lakes.
As of this afternoon, statewide reservoir storage is at 69.8% of capacity compared to 65.4% on this date in 2011. A low of 58.5% was recorded on 11-18-2011.
The table below summarizes storage capacities for the first 2 weeks of August 2023 compared to 2011:
2023 Capacity
2023 Departure
2011 Capacity
2011 Departure
Conroe
92.5%
-1.60
82.0%
-4.05
Houston
96.4%
-.42
81.0%
-6.50
Livingston
89.0%
-2.38
90.0%
-2.08
Texanna
77.2%
-3.83
52.0%
-9.62
Somerville
79.0%
-2.90
49.0%
-8.06
Travis
39.4%
-47.96
43.0%
-44.50
Buchanan
49.7%
-22.55
51.0%
-23.00
Lake Conroe and Houston are much better off than in 2011 with Lake Livingston being nearly the same and both Somerville and Texanna significantly better off in 2023 versus 2011. This matches well with the rainfall trends experienced in late Spring over the area which for the most part filled Houston, Conroe, Somerville, and Texanna to near capacity, allowing the recent dryness to be well handled.
This was not the case in 2011 when a very dry spring and dryness from late 2010 was already depleting capacities prior to the summer increased demand and evaporation losses.
Central Texas Lake Levels Lower in 2023
However, across central Texas at Travis and Buchanan, conditions are worse at this point than in 2011. Travis is 3.46 ft lower in 2023 than in 2011 and Buchanan is 0.45 ft lower.
Central Texas and the highland lakes chain have been in drought conditions since the summer of 2022 and rainfall this spring was not as significant in this area compared to coastal areas of the state and SE TX, so lake inflows have been very low and evaporation and demand maximized.
Heat Comparison
In addition to the drought conditions, it has been brutally hot. But how does 2023 compare to 2011 with respect to 100 degree or hotter afternoons? This is only part of the story of the heat of 2023, as overnight low temperatures have also been warm.
College Station has recorded 42 days with a morning low at or above 80 degrees, BUSH IAH 41, and Hobby 44. However, Galveston has recorded 64 days this summer at or above 80 degrees for a morning low.
The above average Gulf of Mexico waters are resulting in exceptional overnight heat along the coast.
Jeff Lindner, Harris County Meteorologist
Days At or Above 100
Days At or Above 105
2023
2011
2023
2011
BUSH IAH
33
34
3
2
Hobby
28
14
1
0
Conroe
38
38
5
0
College Station
52
51
22
9
With the exception of Hobby Airport, 2011 and 2023 are nearly tied for the number of 100 degrees days up to 8-23. Hobby Airport has surpassed 2011 by 14 days.
More significant is the number of days at or above 105 with College Station crushing 2011 by 13 days. All sites have recorded more 105+ degree days in 2023 compared to 2011. The afternoon high temperatures have been higher in 2023 than in 2011 especially at Conroe and College Station.
Most of this has occurred in the last 3-4 weeks as the ground has dried and the influence of high dewpoints from the Gulf has become less. That has let afternoon temperatures spike higher compared to June and July.
By Jeff Lindner, Director Hydrologic Operations Division/Meteorologist, Harris County Flood Control District, on 8/23/2023
2185 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/08/Drought-Comparison.png?fit=1100%2C800&ssl=18001100adminadmin2023-08-23 18:55:102023-08-23 18:56:39Drought Comparison – 2011 to 2023
The massive $1.77 billion expansion of the 120-acre Northeast Water Purification Plant near Summerwood is now well into its last phase. The last update to the expansion website is dated May 23, 2023 and estimates completion in 2025. Contractors have made considerable progress since May. This satellite image is dated 6/14/23. Note the area on the far right at the eastern side of the plant. That area contains most of the new construction activity.
Landsat Photo in Google Earth from June 2023
Aerial Photos Taken 8/12/23
Compare the photos below of the Northeast Water Purification Plant taken just two months later. They were all taken on 8/12/23.
Looking SW from NE Corner of plant.Close up looking south.Wider shot looking N from SE corner of plant. White circle will contain a giant water storage tank.Looking W at entire plant. Note NE corner of Beltway 8 beyond plant and Atasocita Landfill in upper right.Looking ENEtoward Lake Houston
5X Capacity Increase Will Help Reduce Subsidence
The Northeast Water Purification Plant is designed to help ensure Houston’s water supply while reducing groundwater usage. Pumping groundwater at a rate greater than nature replaces it can cause irreversible subsidence. Subsidence has been linked to increased risk of flooding and structural damage.
The physical site above contains three major sections.
The original plant which can treat 80 million gallons per day (foreground)
First expansion phase (middle)
Second expansion phase (far end).
In May, Phase One was nearing completion and expected to be ready soon. Phase Two is the major focus of efforts now.
Because Lake Houston is so shallow, turbidity increases rapidly during rainfall events. Accordingly, the partners have incorporated both wet- and dry-weather technologies into the treatment plant, so operators can switch nimbly as needed.
Innovative treatment strategies like chlorine dioxide, ozonation and biological filtration have been proven at other Texas facilities using similar source waters. Given the broad range of raw water qualities, they will help the City preserve high-quality finished water and deliver more of it.
Majority of Water Used by Industry
Houston Public Works Drinking Water Operations (DWO) currently serves about 2.2 million people. And Harris County’s population alone is projected to expand to 5.5 million people by 2050. But serving all those extra people is only half the battle.
Many Sources Help Meet Demand, Protect from Drought
To meet demand DWO has three water treatment plants and 49 groundwater production facilities. They span four counties and 600 square miles, making Houston’s system one of the most complex in the nation.
And to feed those plants, the City of Houston owns a 70% share of Lake Livingston, a 70% share of Lake Conroe, 100% of Lake Houston and a 70% share of the future Allen’s Creek Reservoir on the Brazos River.
The variety of sources help sustain a growing population through droughts, such as the one we are in now. Corporations evaluate such factors when choosing where to expand. For more information about Houston’s water supply, check this informative history, written by Susan Smyer in 2008.
Posted by Bob Rehak on 8/22/2023
2184 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/08/20230812-RJR_2264.jpg?fit=1100%2C733&ssl=17331100adminadmin2023-08-22 11:50:102023-08-22 11:50:11Northeast Water Purification Plant Expansion Now in Last Phase
Heat Records and Water-Use Restrictions
This is a bit off topic for a flood blog, but it affects tens of thousands of readers. Late yesterday, after multiple heat records were broken across the region, the City of Houston announced water-use restrictions going into effect Sunday, August 27, 2023. Let me address the heat first, water restrictions second. Then I’ll discuss rain chances and the tropics.
Heat Records Shattered Across Houston Region
Yesterday, the Houston area experienced another unrelenting afternoon of scorching temperatures. Many areas reached the mid- to upper-100’s with a few areas into the low 110’s.
High Temperatures on Thursday, 8/24/23
BUSH IAH: 109 (tied the all time record high, broke daily record high of 105 from 1980)
Huntsville: 111 (shattered record high of 102 from 2011…daily record high broken by 9 degrees)
College Station: 111 (broke record high of 107 from 2010)
Hobby: 107 (broke record high of 100 from 1980)
Conroe: 108 (broke record high of 105 from 1922…101 year old record)
Brenham: 107 (broke record high of 106 from 1980)
Sugar Land: 107 (broke record high of 101 from 2011)
Wharton: 106 (shattered the record high of 99 from 1911…112 year old record)
Cleveland: 109 (broke record high of 104 from 1980)
Crockett: 109 (broke record high of 106 from 2011)
CoH Water-Use Restrictions
According to a City of Houston press release, Houston has entered Stage Two of the City’s Drought Contingency Plan. Due to intense heat and a significant drop in annual rainfall. Effective August 27, 2023, mandatory water-use restrictions will go into effect. They apply to the entire City:
Violations of watering times will get you a written warning for the first violation. Any subsequent violations are subject to a fine up to $2,000 for each occurrence; see Section 54.001 of the Texas Local Government Code.
Easy Ways to Conserve Water
Here are some easy ways to conserve water:
For more water-saving tips, visit www.givewaterabreak.org.
Rain Chances
The high-pressure ridge parked over us for the last two months is giving a little bit of ground. Yesterday, thunderstorms finally overcame subsidence in the super-heated afternoon air mass. The gage at the West Lake Houston Parkway bridge recorded 0.44 inches of rain. Despite several downed trees, people cheered because of our deep drought.
According to Jeff Lindner, Harris County Meteorologist, as high pressure moves west, weak disturbances may approach the area from the east and northeast.
Combined with high temperatures in the low- to mid-100’s, scattered thunderstorms will be possible.
Wildfire Risk Remains
Thunderstorms come with the threat for lightning-induced wildfires. One such fire started yesterday in the Humble area. Lightning strikes will be possible each day and strong gusty winds can quickly fan fires.
Additionally, wind direction and speeds can quickly change near and around thunderstorms creating very hazardous conditions for ground crews. Multiple fires caused by a single thunderstorm can quickly overwhelm local resources. So use extra caution. Burn bans remain in effect.
Western Caribbean Sea
An area of low pressure has crossed Central America into the western Caribbean Sea. It should move north toward Florida. As of this morning, the National Hurricane Center gave it a 70% chance of formation during the next 7 days.
However, it remains unclear where exactly any surface low will form and how it may interact with the surrounding landmasses. Additionally, there may be wind shear to contend with in the southeastern Gulf of Mexico. At this time, models predict varying intensity as the storm moves north.
Currently, this system does not pose a threat to Texas. But watch for winds that could enhance our local fire weather.
Posted by Bob Rehak on 8/25/2023 based on information from Jeff Lindner, Harris County Meteorologist, and City of Houston
2187 Days since Hurricane Harvey
Drought Comparison – 2011 to 2023
By Jeff Lindner, Harris County Flood Control District’s Director Hydrologic Operations Division/Meteorologist, with a few minor edits for a non-technical audience.
There have been many comparisons of this summer to that of 2011 with respect to the heat and drought. Below, see the comparison of drought, water supply storage, and heat between 2011 and 2023.
Rainfall (Jan 1 to Aug 23)
Rainfall departures in 2023 were tempered by a wet April and May over much of the area, while in 2011 drought conditions in the spring were some of the worst ever recorded with many areas recording their driest spring ever. 2011 was also preceded by dryness in late 2010 that helped to worsen the 2011 drought conditions and water supply concerns.
Rainfall at Hobby Airport in 2011 (Feb-May) was only 1.31 inches compared to 2023 of 11.85 inches.
While it is clear that 2011 was worse with respect to lack of rainfall, the abrupt change in rainfall from late spring into the summer of 2023 has “shocked” vegetation across the region.
Additionally, it has been hotter to some degree (especially overnight) in 2023 and the flash drought has been severe with nearly the entire area drought free in early June to all of the area in severe to extreme drought as of August 15th.
The very warm maximum temperatures and record “high” low temperatures over the region have resulted in rapid degradation of vegetation health. Tree losses were staggering in 2011 and the area is starting to see losses mounting in 2023, but far below what was experienced at this point in 2011.
Comparison of Drought Conditions, Extents
In 2011, exceptional drought covered most of the state.
In 2023, exceptional drought is minuscule by comparison.
Reservoir Storage
2011 also featured significant drawdown on area lakes and water supply reservoirs as the longer duration “hydrological” drought resulted in record or near record low inflows to several lakes.
As of this afternoon, statewide reservoir storage is at 69.8% of capacity compared to 65.4% on this date in 2011. A low of 58.5% was recorded on 11-18-2011.
The table below summarizes storage capacities for the first 2 weeks of August 2023 compared to 2011:
Lake Conroe and Houston are much better off than in 2011 with Lake Livingston being nearly the same and both Somerville and Texanna significantly better off in 2023 versus 2011. This matches well with the rainfall trends experienced in late Spring over the area which for the most part filled Houston, Conroe, Somerville, and Texanna to near capacity, allowing the recent dryness to be well handled.
This was not the case in 2011 when a very dry spring and dryness from late 2010 was already depleting capacities prior to the summer increased demand and evaporation losses.
Central Texas Lake Levels Lower in 2023
However, across central Texas at Travis and Buchanan, conditions are worse at this point than in 2011. Travis is 3.46 ft lower in 2023 than in 2011 and Buchanan is 0.45 ft lower.
Central Texas and the highland lakes chain have been in drought conditions since the summer of 2022 and rainfall this spring was not as significant in this area compared to coastal areas of the state and SE TX, so lake inflows have been very low and evaporation and demand maximized.
Heat Comparison
In addition to the drought conditions, it has been brutally hot. But how does 2023 compare to 2011 with respect to 100 degree or hotter afternoons? This is only part of the story of the heat of 2023, as overnight low temperatures have also been warm.
College Station has recorded 42 days with a morning low at or above 80 degrees, BUSH IAH 41, and Hobby 44. However, Galveston has recorded 64 days this summer at or above 80 degrees for a morning low.
With the exception of Hobby Airport, 2011 and 2023 are nearly tied for the number of 100 degrees days up to 8-23. Hobby Airport has surpassed 2011 by 14 days.
More significant is the number of days at or above 105 with College Station crushing 2011 by 13 days. All sites have recorded more 105+ degree days in 2023 compared to 2011. The afternoon high temperatures have been higher in 2023 than in 2011 especially at Conroe and College Station.
Most of this has occurred in the last 3-4 weeks as the ground has dried and the influence of high dewpoints from the Gulf has become less. That has let afternoon temperatures spike higher compared to June and July.
By Jeff Lindner, Director Hydrologic Operations Division/Meteorologist, Harris County Flood Control District, on 8/23/2023
2185 Days since Hurricane Harvey
Northeast Water Purification Plant Expansion Now in Last Phase
The massive $1.77 billion expansion of the 120-acre Northeast Water Purification Plant near Summerwood is now well into its last phase. The last update to the expansion website is dated May 23, 2023 and estimates completion in 2025. Contractors have made considerable progress since May. This satellite image is dated 6/14/23. Note the area on the far right at the eastern side of the plant. That area contains most of the new construction activity.
Aerial Photos Taken 8/12/23
Compare the photos below of the Northeast Water Purification Plant taken just two months later. They were all taken on 8/12/23.
5X Capacity Increase Will Help Reduce Subsidence
The Northeast Water Purification Plant is designed to help ensure Houston’s water supply while reducing groundwater usage. Pumping groundwater at a rate greater than nature replaces it can cause irreversible subsidence. Subsidence has been linked to increased risk of flooding and structural damage.
The physical site above contains three major sections.
In May, Phase One was nearing completion and expected to be ready soon. Phase Two is the major focus of efforts now.
Together the first and second expansions will produce 320 million gallons per day, bringing the total treatment capacity to 400 million gallons.
Plant Will Handle Wide Range of Turbidity
Because Lake Houston is so shallow, turbidity increases rapidly during rainfall events. Accordingly, the partners have incorporated both wet- and dry-weather technologies into the treatment plant, so operators can switch nimbly as needed.
Innovative treatment strategies like chlorine dioxide, ozonation and biological filtration have been proven at other Texas facilities using similar source waters. Given the broad range of raw water qualities, they will help the City preserve high-quality finished water and deliver more of it.
Majority of Water Used by Industry
Houston Public Works Drinking Water Operations (DWO) currently serves about 2.2 million people. And Harris County’s population alone is projected to expand to 5.5 million people by 2050. But serving all those extra people is only half the battle.
Many Sources Help Meet Demand, Protect from Drought
To meet demand DWO has three water treatment plants and 49 groundwater production facilities. They span four counties and 600 square miles, making Houston’s system one of the most complex in the nation.
And to feed those plants, the City of Houston owns a 70% share of Lake Livingston, a 70% share of Lake Conroe, 100% of Lake Houston and a 70% share of the future Allen’s Creek Reservoir on the Brazos River.
Lake Livingston supplies water to Lake Houston and the Northeast Water Purification Plant through the Luce Bayou Inter-Basin Transfer Project.
The variety of sources help sustain a growing population through droughts, such as the one we are in now. Corporations evaluate such factors when choosing where to expand. For more information about Houston’s water supply, check this informative history, written by Susan Smyer in 2008.
Posted by Bob Rehak on 8/22/2023
2184 Days since Hurricane Harvey