Probably not everyone will be called on to speak, but we want the committee to know that this affects vast numbers of people. It’s CRITICAL to communicate how many of us are negatively affected by existing and planned sand mines, quarries, concrete plants, and other APOs.
All of the House Interim Committee members will be present and this will be similar to speaking in front of the committee at the Capitol in Austin–but online.
Speakers will also come from the Hill County where APOs are severely impacting quality of life.
Examples of Problems in Lake Houston Area
Mouth bar on the West Fork San Jacinto that mostly formed during Hurricane Harvey. It backed up water and contributed to flooding thousands of homes and businesses. Much of the sediment came from 20 square miles of sand mines immediately upstream.Cleanup cost to state and federal governments so far: about $150 million.The day the West Fork (right) ran white after the LMI Mine upstream put 56 million gallons of process wastewater into the drinking water for 2 million people (Source: TCEQ).Breach at Triple PG mine one White Oak Creek emitted process wastewater into headwaters of Lake Houston, the source of drinking water for 2 million people.Attorney General is suing mine for approximately $1 million.Concentrated silt after sand is washed. Exposed in floodway of the San Jacinto West Fork.River mining without a permit at the Spring Wet Sand and Gravel Plant on the west fork.
Speak for Up to 3 Minutes
Be prepared to speak for up to three minutes about how YOU personally have been or will be impacted by quarries, concrete batch plants, or asphalt plants. Pick one or two of these key issues that most affect you personally:
???? Air particulate emissions ???? Water use and availability ???? Water pollution and flooding ???? Rapid development of APOs without adequate regulatory oversight, mine planning, or reclamation ???? Truck traffic ???? Nuisance issues: blasting, noise, odor, light trespass, visible blight ???? Economic impacts, devaluation of property
URGENT: DO TODAY BEFORE 5pm
Just send in an email requesting to speak. You’ll have a week to plan and prep. Thanks for helping protect our families and community!
If possible, it is VERY IMPORTANT to speak at this meeting. However, if you aren’t selected to speak, or you don’t get your request submitted in time, there will be an additional opportunity later this month to submit written testimonial. We’ll send more info on this in the upcoming days and weeks.
Two world-class geologists, Tim Garfield and R.D. Kissling, both of whom live in the Lake Houston Area, agreed (at ReduceFlooding.com’s request) to offer their opinions on what would be the best strategy for dredging near the San Jacinto West Fork Mouth Bar. Garfield and Kissling helped bring mouth bar issues to the attention of the public after Harvey. Both have followed various dredging programs in that area closely ever since.
Looking west across the mouth bar on 9/11/2020 while hovering over Kings Point. Suspended sediment shows that main current of river is between remainder of the above-water portion of the mouth bar and Atascocita Point on the upper left.Photo taken 9/11/2020.
However, none of the various parties involved has volunteered to share their thinking about objectives and strategies behind mouth bar dredging alternatives. That’s why I asked Garfield and Kissling to offer their thoughts on what constituted the best strategy. Both worked for one of the world’s largest oil companies at the very highest levels.
Old Bathymetric Maps No Longer Valid
The first thing they realized was that they didn’t have enough data to make informed recommendations. The last published bathymetric maps were based on surveys taken before Imelda and before the Corps’ mouth-bar dredging.
Gathering Own Data
So Garfield and Kissling gathered their own data – with sonic depth finders, GPS, and a 14-foot pole with depth markings. They started upstream of the mouth bar, where the Army Corps finished its Emergency West Fork Dredging program near Kings Harbor. And they worked their way downstream beyond FM1960 to the railroad bridge.
Scope of Garfield/Kissling survey
Found Underwater Plateau 20′ High and 3 Miles Long
They found an underwater wall approximately 20′ high where the Corps stopped its first dredging program near Kings Harbor. It extended downstream more than 3 miles.
Cross section of river channel shows a rise of almost 20 feet wall on the upstream side of the mouth bar near Kings Harbor and an even greater drop near FM1960. The result: a 3-mile long underwater plateau.
That wall, they say, “…constitutes a significant and abrupt hydraulic barrier that will likely exacerbate flooding and sedimentation.”
That wall is the leading edge of a 3-mile-long underwater plateau.
Garfield and Kissling recommend dredging along the deepest path (see below). They reason that would save money.
Recommended and alternate routes identified by Garfield and Kisslingthat take advantage of deeper water.
“This might not only be the most beneficial dredging plan, but could also be the most cost effective as it leverages the paleo-channel as much as possible,” they say. “It harnesses nature, rather than fighting it.”
The geologists also identified a second possible route farther to the east but still south of the above-water portion of the stream mouth bar (labeled SMB in diagram above).
They caution that hydraulic modeling should be used to decide the best dredging plan. Political considerations drove initial mouth bar dredging rather than data. The Corps was authorized only to dredge an amount that it believed Harvey deposited. “We should be past the politics at this point and looking to get the most bang for our bucks,” say the geologists.
Whichever strategy the City settles on, Garfield and Kissling recommend excavating a channel, not a broad area, to get the best results for the dollars invested.
Objective: Re-establish Full Channel From Kings Harbor to Lake Houston
“This new channel should be no shallower, nor narrower than the upstream dredged channel at its end dredge location (450’ wide x 26’ deep),” say the geologists.
As a minimum, the future dredging plan should re-establish a continuous and down-stream deepening channel volume from where the Corps channel dredging ended to the 1960 bridge.
Tim Garfield and RD Kissling
This will help reduce sediment build up upstream from the plateau. By accelerating water through the blockage, it will let the river carry sediment farther out into the deeper portion of the lake. It will also reduce water backup that contributes to flooding.
Recommendations Consistent With City’s Preliminary Findings
The City has been methodically surveying Lake Houston and is in the process of developing its own maps, objectives and strategies. Stephen Costello, the City’s flood czar said they are not finished with that effort yet. However, he also said that the preliminary information they obtained suggested that a route south of the mouth bar might be the most effective.
Posted by Bob Rehak on 9/25/2020 with thanks to Tim Garfield and RD Kissling
1123 Days after Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/Slide6-1.jpeg?fit=1200%2C900&ssl=19001200adminadmin2020-09-25 12:33:102020-09-25 23:08:43Two Top Geologists Suggest Mouth Bar Dredging Strategy
The Texas Water Development Board (TWDB) has advanced four of five San Jacinto River Authority (SJRA) abridged grant applications to the next round for consideration. TWDB named them as priorities for the 2020 Flood Infrastructure Fund (FIF) cycle. That advances SJRA one step closer to funding for the projects.
SJRA Now Invited to Submit Full Applications
With these rankings, SJRA will now submit full grant applications for four projects for approval. In the two-stage process, applicants first submit an abridged application. TWDB then prioritizes them within the overall available funding capacity.
As with most Texas river authorities, SJRA is not a taxing entity, therefore these large-scale flood mitigation projects require regional and local partnerships as well as grant funding.
“Hundreds of abridged applications were submitted by entities—cities, counties, other political subdivisions—as part of this competitive process. We are very proud SJRA was selected to move ahead in the approval process on four of our five abridged grant applications,” said Chuck Gilman, SJRA Director of Water Resources and Flood Management. “The next step is to find local partners who, along with SJRA, will commit to the local-match funding and in-kind services. These large-scale, impactful projects come with a very high price tag. It will take a regional approach with various funding commitments to see these projects through to completion. The FIF funding is an essential piece of that process.”
Flood Infrastructure Fund Criteria
According to Flood Infrastructure Fund criteria, eligible projects must fall under one of four categories:
Flood Protection Planning for Watersheds
Planning, Acquisition, and Design, Construction/Rehabilitation
Federal Award Matching Funds
Measures Immediately Effective in Protecting Life and Property
TWDB will review the full grant applications and make final selections for grant and loan funding later this year.
Would identify and create a plan for implementing potential sedimentation solutions in the Upper San Jacinto River Basin (Lake Houston watershed). It would evaluate the input, output, and storage of sediment for the entire basin as well as for sub-watersheds.
LMI River Bend Sand Mine on San Jacinto West Fork exposes more than 500 acres of sand to floodwaters.Altogether, sand mines expose approximately 20 square miles of sand along the West Fork to floodwaters in a 20 mile stretch between I-45 and US59.
Would perform a conceptual engineering feasibility study of two potential dam/reservoir locations within the Spring Creek watershed. This is the next phase of the Spring Creek Siting Study, which is currently being completed as part of the San Jacinto Regional Watershed Master Drainage Plan. Harris County Flood Control District leads the Master Drainage Plan effort. SJRA and other regional partners support it.
Would develop a joint reservoir operations and communications strategy for Lake Conroe and Lake Houston. The City of Houston is currently studying new tainter gates for the Lake Houston dam. They could greatly increase the controlled release capacity.
The main goal of the plan: to determine the most efficient and safe operation of the two reservoirs in series. The study would evaluate multiple individual components of a joint operational strategy.
It will evaluate:
Operational synergy between the two reservoirs
Joint notification and communications protocols
Pre-release
Impacts on water supply
Use of forecasting tools.
This project will benefit both water supply and flood mitigation in the region.
Would provide for installation of rain and river/stream gages at three locations identified as critical by San Jacinto County to provide early warning information to the county during storm events.
Locations:
Winters Bayou at State Highway 150
East Fork San Jacinto River at FM 945
Peach Creek at FM 3081.
Rain and river/stream stage data obtained at the sites would be transmitted to SJRA’s ALERT2 network and displayed on SJRA’s Contrail system. The data could be viewed online via SJRA’s website. That lets San Jacinto County staff and residents view the data at any time.
Not Advancing to Next Round
The SJRA had also submitted a first-round grant application to develop preliminary designs for sand traps. The sand traps were supposed to reduce the amount of sediment moving downstream. SJRA confirmed that this grant application will not move forward.
Posted by Bob Rehak on 9/24/2020 based on input from SJRA
1122 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/20200911-RJR_0441.jpg?fit=1200%2C800&ssl=18001200adminadmin2020-09-24 16:04:352020-09-24 16:16:18TWDB Advances 4 of 5 SJRA Grant Applications for Flood Infrastructure Funding
Beta is now off to the east. As of 10:30 am on 9/23/2020, the East and West Forks are well within their banks. So are the lesser tributaries with the exception of Cypress Creek. Lake Conroe is still below 200 feet. And Lake Houston, thanks to a pre-release, is only about a tenth of an inch above normal so far, though it is rising this morning.
4-Day Rainfall Total for Storm
The radar image below shows the total rainfall accumulations across the Houston Area for the duration of the storm, starting at 2:37p.m. on 9/19/2020. This was a story of selective drenching. The south and southwest sides of the city received four times as much rain as Kingwood, Crosby and Atascocita. And more than twice as much rain as Humble. They got caught under a training feeder band; we missed it.
Source: RadarScope Pro
Here are the totals associated with the different colors above:
Light green = 2 inches
Dark green = 3 inches
Light purple = 4 inches
Dark purple = 5 inches
Light blue = 6 inches
Dark blue = 7 inches
Yellow = 8 inches
Orange = 10 inches
Red = 12 inches
Brown = 15 inches
Harris County Flood Warning System Shows Slightly Higher Totals
The radar image may understate the totals. The four-day-rain totals from Harris County Flood Control District gages mirror the pattern above, but show slightly higher numbers. For instance, the radar image shows 3-4″ for Kingwood, but the gages show 4-5″. I live in Kingwood and my personal weather station recorded 4.92 inches for the same four-day period.
Regardless, those caught under training feeder bands on the south and southwest sides got drenched. The Lake Houston Area escaped the worst of the rains.
While these totals are within the ranges predicted at the start of the storm, they definitely fall on the low side. Why?
Space City Weather offered this. “We had two big allies over the last week; moderate wind shear to prevent Beta from strengthening, and dry air over the state from a weak front that disrupted its circulation and prevented the formation of several, thick bands of rainfall. Instead, if you watched the radar closely, there was only ever really one strong band that was perhaps 10 to 15 miles across. This just happened to set up over Houston on Monday and Monday night…”
The Lessons of Beta
Even the heaviest rains we received were about one fourth of what Harvey dropped (40-60 inches). Beta was not unusual. As Space City Weather offered, “A tropical storm that brings a range of 5 to 15 inches rain across Houston, with rainfall rates below 2 inches per hour, is a fairly common event.”
Yet some areas still flooded. In my opinion, this underscores the need for:
HCFCD to continue and accelerate (if possible) its work.
All governments in the region to adopt higher regulations for new developments that reflect Atlas-14 rainfall tables.
People at all levels of government (Federal, State, Counties, Cities) to work together and make flood mitigation a top priority.
Leaders throughout the region to realize that we are all in this together. Slowing floodwater down in one area while speeding it up in another is a losing battle that undermines the economic heart of the region.
Posted by Bob Rehak on 9/23/2020
1121 Days after Hurricane Harveyand 370 after Imelda
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/Total-Accumulation-Beta.jpg?fit=1200%2C812&ssl=18121200adminadmin2020-09-23 10:52:472020-09-23 10:57:30Lake Houston Area Lucked Out With Beta
The center of Beta is currently near Bay City and moving ENE. For the next 24 hours, the National Hurricane Center (NHC) forecasts maximum winds at 30 mph.
If any readers in the Lake Houston Area felt left out by Beta, tonight could be your night. According to the NHC, Harris County Meteorologist Jeff Lindner and Space City Weather, models continue to show that a heavy band of rainfall will begin to develop over the next few hours across the northern portions of Harris County.
Beta Tuesday evening at 5PM, courtesy of RadarScope. The bands are moving from SE to NW. But the forward motion of the storm is perpendicular, from SW to NE. That could push new feeder bands into the Lake Houston Area later tonight.
Current Radar Trends Show Storm Moving Toward Northeast Harris County
“Current radar trends show what may be the start of this banding feature from Downtown Houston to Jersey Village to Waller where a broken band of heavy to excessive rainfall is forming,” said Lindner at 4pm today.
He continued, “Models show this band continuing well into the evening and overnight hours across much of northern and northeastern Harris County into Liberty County. Training of heavy rainfall is likely with this banding along with flash flooding.”
Additional rainfall of 4-7 inches will be possible over the northern portions of Harris County into Liberty County and possibly southern Montgomery County with isolated totals of 10-12 inches possible.
JEFF LINDNER, HARRIS COUNTY METEOROLOGIST
(Update At 9:10 PM) The radar image above looked like this and heavy rain had started in Kingwood.
Source: RadarScope
However, in the upper San Jacinto Watershed, the expected rainfall amounts will likely produce flooding only on Cypress and Little Cypress Creeks.
In other parts of Houston, the following streams could flood:
Greens Bayou
Halls Bayou
Hunting Bayou
White Oak Bayou tributaries
Cedar Bayou
Gum Gully
Langham Creek
Horsepen Creek
South Mayde Creek
Bear Creek
The largest threat at this point is street flooding. So move your cars out of the street tonight.
West Fork Still At Normal Level
At 4PM CDT Tuesday, the West Fork San Jacinto at US59 is still nearly seven feet from coming out of its banks.
Flood Warning System Shows Effects of Heavy Training
The high rainfall gradient across Harris County should the effects of heavy training by Beta’s feeder bands during the last 48 hours. Places under the bands received 12 to 14 inches of rains. Meanwhile, the Lake Houston Area received only around an inch so far.
Beta’s heaviest rainfall until now focused on SW Harris County. Figures shown represent last 48 hours.Source: Harris County Flood Warning System.Note 13.44 inches on HW288!
Worst Likely Over for SW Harris County
Some heavy rainfall is still possible in already hard-hit southern and southwestern Harris County. However, where and potentially how much may fall in that area is uncertain.
Beta Continuing to Weaken
High-resolution visible satellite imagery, surface observations, and NOAA Doppler weather radar data from San Antonio and Houston, Texas, indicate that Beta has continued to weaken.
Cloud tops only extend up to 25,000- 30,000 ft, mainly near and northeast of the center. However, they are quite prodigious rain-producers. Rainfall totals of 13-14 inches having been measured across portions of the Houston metropolitan area thus far.
The Future of Beta
Since Beta should remain inland throughout the forecast period, the cyclone is not expected to regain tropical storm status. Beta should degenerate into a remnant low within 36 hours and dissipate over Mississippi or Alabama in 96 hours, if not sooner.
At 4 p.m. Tuesday, September 22, 2020, the National Hurricane Center (NHC) issued its last update on Beta.
Said Space City Weather, “The good news is that this mess will begin to clear our of here by Wednesday morning, if not sooner for some areas. The bad news is that we’ve got to get through later today and tonight.”
Posted by Bob Rehak on 9/22/2020 based on data from HCFCD, NHC and Space City Weather
1120 Days after Hurricane Harvey and 369 since Imelda
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/Screen-Shot-2020-09-22-at-5.15.09-PM.jpg?fit=1200%2C759&ssl=17591200adminadmin2020-09-22 17:19:482020-09-22 21:18:04Lake Houston Area Could Be in Beta’s Crosshairs Tonight
At 10 a.m. CDT, the National Hurricane Center (NHC) downgraded Tropical Storm Beta to a tropical depression. The NHC also cancelled the tropical storm and storm surge warnings that were in effect. However, flash flood warnings remain in effect for large parts of the seven-county Houston region, especially the southern part. A flash flood watch remains in effect for the entire region.
RadarScope split image. Left half shows track of active storms as of 9:06AM CDT. Right half shows total rainfall accumulation for Beta. Note band of extreme rainfall near Sugar Land and sharp drop-off near Kingwood.
Flash Flood Warnings and Watches
A flash flood warning means that flooding is in progress. A Flash Flood Watch means that conditions may develop that lead to Flash Flooding.
Source: National Weather Service. Updated at 10:29 a.m. 9/22/2020. Reddish area = Flash flood warning. Green = Flash flood watch.
Lake Conroe/Lake Houston Within Banks
Neither Lake Conroe, nor Lake Houston have yet been adversely affected by Beta.
The level of Lake Conroe stands at 199.63 feet. Normal conservation pool equals 201.
According to the Coastal Water Authority, Lake Houston is at:
Tropical Storm Beta moved inland last night around 10 p.m. The center is now near Victoria and moving toward the northwest near 3 mph. The National Hurricane Center predicts Beta will weaken and stall today, but will then begin to move slowly toward the Houston Area tonight. They expect forward speed to increase Wednesday through Friday.
At the moment, maximum sustained winds are near 40 mph with higher gusts. Tropical-storm-force winds extend outward up to 105 miles from the center. A sustained wind of 39 mph and a gust to 47 mph were recently reported at Victoria, Texas. But at the moment, my wind gage is reading ZERO here in Kingwood.
Yesterday’s Heaviest Rains Narrowly Missed Lake Houston Area
Yesterday’s heaviest rainfall narrowly missed us. While the Lake Houston Area received around an inch of rain, the southwest corner of Loop 610 received 11.64 inches due to a training feeder band.
The main threat today to the Lake Houston Area is having a similar feeder band train over us.
Below are the two-day storm totals so far for Beta in Harris County.
For the middle and upper Texas coast, additional rainfall of 6 to 12 inches with isolated storm totals up to 20 inches is expected.
Significant flash and urban flooding is occurring south and west of the Lake Houston Area and will continue today.
RadarScope image as of 6:30 a.m. CDT on 9/22/2020. Center of storm located over Victoria in lower left.
Minor river flooding is likely. Rainfall totals of 3 to 5 inches are expected northward into the ArkLaTex region and east into the Lower Mississippi Valley through the end of the week.
Track
Steering currents around the storm are now collapsing, and Beta is expected to meander during the next 12-24 hours. By this time tomorrow, however, a mid-level trough over west Texas should begin moving eastward and scoop Beta up. That will cause the storm to move toward the east-northeast near or just inland of the upper Texas coast through 36 hours.
After that time, Beta will likely turn northeastward, moving farther inland across Louisiana and Mississippi before dissipating in about 4 days. Beta should weaken to a tropical depression in about 24 hours before it reaches the Lake Houston Area. It will become a remnant low in 2-3 days.
Tornadoes
A tornado or two could occur today near the upper Texas and southwestern Louisiana coasts.
Surf
Swells generated by a combination of Beta and a cold front over the northern Gulf of Mexico will continue along the coasts of Louisiana and Texas during the next couple of days. These swells are likely to cause life-threatening surf and rip current conditions.
Winds
It is unlikely we will see tropical storm strength winds in the Lake Houston Area.
Winds will increase today as Beta moves in our direction. But Beta is barely at tropical storm strength now and is weakening. The most likely arrival time for the heaviest winds: tonight at 8 p.m.
Flash-Flooding Potential
A flash flooding event is in progress over Harris County. “Numerous roadways are flooded. Avoid travel.
Jeff Lindner, Harris County Meteorologist
At this time (8am Tuesday, 9/22/2020), the main problem areas are south and west of Houston near the coast. However, that could change as the storm moves toward us.
Channel Status in Harris County. Green means “within banks.” Yellow means “flooding possible.” Red means “flooding likely.”
See data on the problem areas below.
Harris County Flood Control District – Hydrologic Operations Division Rain and Channel Status Report at 09/22/2020 07:30 AM ============================================
Maximum Rainfall the last 1hr 1.56 inches – Gage 435 @ 435 Willow Water Hole @ Willowbend Boulevard 1.4 inches – Gage 440 @ 440 Brays Bayou @ Rice Avenue 1.24 inches – Gage 370 @ 370 Sims Bayou @ SH 288 1.16 inches – Gage 190 @ 190 Clear Creek @ SH 288 1.04 inches – Gage 430 @ 430 Brays Bayou @ Stella Link Road
Maximum Rainfall the last 6hrs 5.72 inches – Gage 430 @ 430 Brays Bayou @ Stella Link Road 5.0 inches – Gage 2265 @ 2265 Buffalo Bayou @ Piney Point Rd 4.56 inches – Gage 440 @ 440 Brays Bayou @ Rice Avenue 4.6 inches – Gage 2260 @ 2260 Buffalo Bayou @ San Felipe Drive 4.48 inches – Gage 435 @ 435 Willow Water Hole @ Willowbend Boulevard 4.4 inches – Gage 2270 @ 2270 Buffalo Bayou @ West Beltway 8 4.44 inches – Gage 2255 @ 2255 Briar Branch @ Campbell Road 4.52 inches – Gage 420 @ 420 Brays Bayou @ South Main Street
Maximum Rainfall the last 24hrs 11.04 inches – Gage 180 @ 180 Clear Creek @ Mykawa Road 11.0 inches – Gage 370 @ 370 Sims Bayou @ SH 288 10.88 inches – Gage 435 @ 435 Willow Water Hole @ Willowbend Boulevard 10.56 inches – Gage 445 @ 445 Willow Water Hole @ Landsdowne Drive 10.36 inches – Gage 430 @ 430 Brays Bayou @ Stella Link Road 10.12 inches – Gage 175 @ 175 Clear Creek @ Pearland Parkway 10.12 inches – Gage 380 @ 380 Sims Bayou @ Hiram Clark Rd 9.96 inches – Gage 440 @ 440 Brays Bayou @ Rice Avenue 9.92 inches – Gage 150 @ 150 Clear Creek @ Country Club Drive 9.84 inches – Gage 145 @ 145 Clear Creek @ Dixie Farm Road 9.8 inches – Gage 190 @ 190 Clear Creek @ SH 288 9.6 inches – Gage 460 @ 460 Brays Bayou @ Gessner Road 9.4 inches – Gage 105 @ 105 Marys Creek @ Winding Road 9.44 inches – Gage 360 @ 360 Sims Bayou @ Martin Luther King Road 8.68 inches – Gage 135 @ 135 Clear Creek @ FM 2351 8.56 inches – Gage 465 @ 465 Brays Bayou @ Beltway 8 8.36 inches – Gage 115 @ 115 Cowart Creek @ Baker Road 8.28 inches – Gage 140 @ 140 Turkey Creek @ FM 1959
Stream Water Surface Elevation Data
Out of Banks: Gage 110 @ Clear Creek @ I-45 Gage 120 @ Clear Creek @ FM 528 Gage 130 @ Clear Creek @ Bay Area Boulevard Gage 135 @ Clear Creek @ FM 2351 Gage 145 @ Clear Creek @ Dixie Farm Road Gage 175 @ Clear Creek @ Pearland Parkway Gage 180 @ Clear Creek @ Mykawa Road Gage 610 @ Taylors Bayou @ Shoreacres Boulevard Gage 2150 @ South Mayde @ Greenhouse Road
Near Bankfull: Gage 100 @ Clear Lake 2nd Outlet @ SH 146 Gage 140 @ Turkey Creek @ FM 1959 Gage 150 @ Clear Creek @ Country Club Drive Gage 160 @ Beamer Ditch @ Hughes Road Gage 170 @ Clear Creek @ Nassau Bay Gage 190 @ Clear Creek @ SH 288 Gage 200 @ Taylor Lake @ Nasa Road 1 Gage 410 @ Brays Bayou @ Lawndale Street Gage 420 @ Brays Bayou @ South Main Street Gage 430 @ Brays Bayou @ Stella Link Road Gage 440 @ Brays Bayou @ Rice Avenue Gage 460 @ Brays Bayou @ Gessner Road Gage 480 @ Keegans Bayou @ Roark Road Gage 710 @ San Jacinto River @ Rio Villa Gage 720 @ San Jacinto River @ US 90 Gage 740 @ Lake Houston @ FM 1960 Gage 1610 @ Greens Bayou @ Normandy Street Gage 1720 @ Cedar Bayou @ SH 146 Gage 2115 @ Langham Creek @ Clay Rd Gage 2210 @ Buffalo Bayou @ Turning Basin Gage 2253 @ Buttermilk Creek @ Moorberry Lane Gage 2255 @ Briar Branch @ Campbell Road Gage 2265 @ Buffalo Bayou @ Piney Point Rd
Key Messages
Posted by Bob Rehak on 9/22/2020 at 8am based on data from Jeff Lindner, Harris County Meteorologist, the National Hurricane Center, Harris County Flood Warning System and RadarScope
1120 Days After Hurricane Harvey and 369 since Imelda
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/Screen-Shot-2020-09-22-at-6.20.22-AM.jpg?fit=1200%2C638&ssl=16381200adminadmin2020-09-22 08:07:012020-09-22 08:23:09Beta Stalling Onshore Around Victoria; Will Start Moving Toward Houston Tonight
As of 10:00 a.m. Monday morning, the National Hurricane Center (NHC) still shows the center of Tropical Storm Beta located offshore. The latest forecasts from the NHC predict that Beta will move onshore near Matagorda Bay, then move up the coastline toward League City.
The NHC also advises that the storm has picked up speed. Yesterday, they estimated 3 mph; today 7 mph.
No one seems to predict that the storm will intensify before landfall.
“Dry air continues to work into and wrap around the large wind field of Beta yielding the disorganized precipitation field with the system.”
Lake Houston Area is the blue dot in the center of the swirl. Red line is predicted path of Beta.Source: Weather Live.
Main Threat: Storm Surge
At this time, Beta’s main threat is to the coastline through storm surge. “Tides are currently running 4.0-4.5 feet in Clear Lake and across coastal sections of Harris County with several sites near the Gulf beaches running 4.0-4.5 feet. Coastal flooding is ongoing and will continue for much of the day. Several roadways are underwater along the coast and around Galveston Bay,” says Lindner.
Lindner continues, “As Beta makes landfall along the middle Texas coast later today, the storm will begin to slow and then turn ENE toward the upper TX coast. It will slowly weaken along the way. This track will keep onshore flow along the upper Texas coast tonight and Tuesday. Tides will remain high into the high tide tonight. Impacts along the coast will continue through the day and into tonight and likely Tuesday.”
Wind Forecast
The most likely arrival time of tropical storm force winds, if we get them, is later tonight.
Tropical storm force winds already cover a large part of the mid-Texas coast.
The storm will weaken as it moves toward the Houston Area and turn into a tropical depression. The further north you live from the coastline, the less intense winds will be.
Depending on where you live in Houston, you have a 30% to 100% chance of experiencing topical storm force winds. The Lake Houston Area is on the low end of that range. The National Weather Service predicts that the Lake Houston Area has a chance of seeing 39-57 mph winds. But Spaces City Weather advises that Beta is “not a significant wind threat.”
However, note that tropical-storm-force winds currently extend outward up to 175 miles (280 km) from the center of the storm.
Galveston has reported sustained winds of 39 mph and a gust of 43 mph during the past couple of hours.
Rainfall
Dry air has worked into the circulation of Beta, according to Lindner. “This has resulted in a more disorganized and scattered rainfall pattern. However, the system is still capable of heavy rainfall especially near the center later today and in bending structures east of the center for the next 48 hours.”
Models show several banding features developing during the next 48 hours over SE TX, But little consensus exists on where the heaviest rainfall totals may be.
Lindner advises that, “Given that much of the area will reside on the eastern side of a the tropical system, we should keep some level of concern of heavy rainfall and flooding in place through the next 48 hours.”
Lindner predicts that widespread rainfall amounts of 4-8 inches will be possible for areas along and south of I-10 with isolated totals of 10-12 inches under any training feeder bands. Totals to the north of I-10 will likely average 3-5 inches with isolated totals of 6-7 inches.
However, the NHC predicts slightly less rain. See the map below.
As long as the rainfall spreads out over the next 48 hours, most of the creeks and bayous can handle the expected rainfall amounts, Lindner says. But should any training develop, flash flooding would be possible.
Watches and Warnings in Effect
A Storm Surge Warning is in effect for Port Aransas, Texas to Rockefeller Wildlife Refuge, Louisiana. That includes Copano Bay, Aransas Bay, San Antonio Bay, Matagorda Bay, Galveston Bay, Sabine Lake, and Lake Calcasieu.
A Tropical Storm Warning is in effect for Port Aransas Texas to Morgan City Louisiana. That includes the Lake Houston Area.
A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS.
Lindner, the NHC and NWS all warn that tornadoes remain a threat with this storm. Especially, tonight and Tuesday.
Track
Yesterday, models predicted that Beta would track up US59 toward the Humble/Kingwood Area. However, today, forecasters think the storm will track closer to the coast. They put it on a line toward League City.
Wind shear will keep Beta’s track close to the coastline, but it will also affect the cyclone’s intensity along with land interaction. The closer the cyclone stays near the Gulf of Mexico, the more likely that bands of convection containing tropical-storm-force winds will continue to roll onshore the Texas coast through 36-48 hours.
Summary
Flash, urban, and isolated minor river flooding is possible, but the danger is “slight.”
Net: Beta is still a threat. But it may be less of one than yesterday. That’s because of the dry air folding into the system and wind sheer which seem to be weakening it somewhat. Be hopeful, but cautious. Expect several inches of rain and high winds in the next two days with both tapering off Wednesday.
Posted by Bob Rehak on 9/21/2020 at noon based on data from NHC, NWS, Jeff Lindner, Space City Weather and Weather Live
1119 Days after Hurricane Harvey and 368 since Imelda
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/Screenshot-2020-09-21-at-11.37.19-AM-scaled.jpg?fit=1183%2C2560&ssl=125601183adminadmin2020-09-21 11:46:032020-09-21 11:52:04Beta Moving Ashore Today Then Likely Tracking Slightly South of Houston
As of mid-day Sunday, all of East Texas now faces some level of excessive rainfall and flash flood risk from Tropical Storm Beta.
The projected path of the storm has shifted inland, so rainfall will reach father north. The latest track now takes the storm on a path right up US59 from Sugar Land to Humble and Kingwood. However, Beta likely be a tropical depression by the time it reaches the north side.
Harris, Montgomery and Liberty Counties (and the whole Houston region) face a high to moderate threat of flooding rains. The first rainbands from Beta have already started to move onshore today, but the heaviest rain will not occur until Monday into Tuesday.
North Houston Under Moderate Flooding Rain Threat
Flash Flood Watch in Effect
The entire region is under a flash flood watch. Coastal areas also face storm surge and tropical storm warnings.
Slow Moving Storm Will Produce Prolonged Rains
Beta is meandering slowly at about 3 mph northwest toward the coastline west of Houston and will then curl back over Houston. It should move inland sometime Monday or Monday night and turn from a storm into a depression by the time it reaches Houston.
However, Beta could dump rain on us from later today all the way through Wednesday.
40-50% Chance of Tropical Storm Force Winds Reaching North Houston
The North Houston Area has a 40-50% chance of seeing tropical storm force winds from Beta.
If the high winds reach this far inland, they would likely arrive Monday evening. Winds extend outward from the center for 195 miles as of Sunday morning.
Feeder Bands Extend Outward 190 Miles
In fact, at 11 a.m. Sunday morning, the first feeder band was approaching the eastern side of Houston, as you can see in the radar image below.
This image shows how the wind and rain from Beta could remain with us for days as the storm’s center wanders around the Gulf.
These feeder bands reach out 190 miles. That is roughly the distance from Houston to San Antonio. So Beta will produce long-duration rainfall from the middle Texas coast to southern Louisiana.
Flash, Urban, and River Flooding Likely
The National Weather Service warns that coastal flooding will remain a threat through midweek with the worst of the storm surge anticipated on Monday and Tuesday.
Elsewhere impacts from the excessive rain include:
Rainfall flooding may prompt evacuations and rescues.
Rivers and tributaries may rapidly overflow their banks.
Small streams, creeks, canals, and ditches may become dangerous rivers.
Flood control systems and barriers may become stressed.
Flood waters may cover escape routes.
Streets and parking lots may become rivers of moving water with underpasses submerged.
Driving conditions may become dangerous.
Many roads and bridges may close with some weakened or washed out.
Lake-Level Situation
According to the SJRA, Beta has the potential to dump up to 8 inches of rain in Montgomery County.
SJRA is operating under standard protocols for a severe weather event and will be onsite at Lake Conroe throughout the duration of Tropical Storm Beta.
Lake Conroe remains 18 inches low, and based on the current forecast, no reservoir releases are expected.
You can monitor stream and river levels in near-real time at Harris County Flood Warning System. Make sure you check out the inundation mapping feature.
Posted by Bob Rehak on 9/20/2020 based on information from the National Weather Service and National Hurricane Center
1118 Days after Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/HGXFloodingRainThreat.png?fit=492%2C745&ssl=1745492adminadmin2020-09-20 12:53:402020-09-20 13:32:59Excessive Rainfall Threat from Beta Spreads Inland
As Tropical Storm Beta bears down on the Houston Area, many people in the Elm Grove/North Kingwood Forest area worry that they might flood again. How likely is that, given the current predictions of 6-10 inches? After all, on May 7 last year, Elm Grove flooded on what was officially a six inch rain according to the nearest gage at West Lake Houston Parkway and the West Fork.
…But Detention Based on Pre-Atlas 14 Rainfall Rates
Even though that’s far more than Woodridge Village had during the May or September floods, the detention calculations by LJA Engineering were based on pre-Atlas 14 rainfall rates. A 100-year rainfall then was about 40% less than the official 100-year rainfall now.
So, the questions is, “How much rain would Beta have to dump on Woodridge Village before it overwhelmed the detention ponds that exist today?”
Figures Used by LJA
The chart below shows the rainfalls that the ponds were designed to hold without flooding. The bench mark its the 24-hour, hundred year rain.
These figures come from the hydrology report submitted by LJA to Montgomery County. A table buried on page 32 of the PDF shows that they based their analysis on a pre-Atlas 14, 100-year storm that dropped 12.17 inches of rain in 24 hours.
From Page 2.1 of LJA Hydrology Report Addendum, 8/28/2018 (page 32 of pdf.)
The ponds should also hold any of the shorter-duration rainfalls in the last column above.
Assumptions Underlying the Answer
To answer the question – How much would it take to flood Elm Grove again? – we need to make several assumptions:
LJA correctly calculated the volume needed.
Contractors actually excavated the volume promised.
With those caveats in mind, it would take 12+ inches of rain in 24 hours to exceed the capacity of the detention ponds currently on Woodridge Village. After that, water would start to overflow.
Short, High-Intensity Downpours Can Cause Different Type of Flooding
However, consider the other durations in the chart above. Seven inches in three hours or nine inches in six hours could also exceed the capacity.
Actually, as you get into these short-duration, high-intensity rainfalls, you introduce the risk of flooding from a second source: overwhelming the capacity of storm drains.
Storm Drains Designed for 2″ Per Hour
The storm drains in Kingwood are designed to convey about two inches of rain per hour. When you exceed that, water begins to back up in the streets. Exceed it enough, and water could actually enter homes – without sheet flow from Woodridge Village.
NHC Rainfall Prediction Spans 5 Days
The six-to-ten inch prediction issued by the National Hurricane Center for Beta spans five days. That’s good news. If ten inches were evenly spread out over five days, the streets, drains and ditches could easily handle two inches per day.
But those short, high intensity rainfalls – when you get two inches in five or ten minutes – represent a real danger. There’s just nowhere for the water to when it comes down that quickly.
Perhaps the Biggest Danger
Even if we got the predicted 6-10 inches all in one day, that’s still, at most, about 80% of the old 100-year rain which the detention was designed for.
I suspect the biggest danger from Beta may be those short, high-intensity cloud bursts or training feeder bands that dump a couple inches in five or ten minutes.
So keep your eye on the rain gage. Sign up for alerts at the Harris County Flood Warning System. Also, keep your eye on the forecasts; uncertainty still exists with Beta, its track and rainfall potential.
Posted by Bob Rehak on 9/19/2020
1117 Days after Hurricane Harvey and 1 year after Imelda
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/09/Rainfall-Table-Page-32-LJA-report.png?fit=730%2C350&ssl=1350730adminadmin2020-09-19 20:11:192020-09-19 20:21:44How Much Rain Would It Take To Flood Elm Grove Again?
