As of 7 pm CDT on 8/19/22, the National Hurricane Center (NHC) gave a tropical disturbance in the Gulf an 80% chance of turning into a named storm today or tomorrow. They call this area of investigation “99L.” Two days ago, the NHC gave this only a 10% chance of developing. But it survived going over the rugged terrain of Central America and is now out over water again where conditions are favorable for development.
Satellite imagery indicates that showers and thunderstorms are getting better organized. Deep thunderstorms have developed near/over this low pressure center.
Satellite photo taken at noon Houston time on 8/18/22.
According to NHC, environmental conditions appear favorable for additional development, and a tropical depression could form as the system moves northwestward across the southwestern and western Gulf of Mexico as early as today. However, by Saturday night, NHC predicts the system will move inland over northeastern Mexico, which will end its chances of development.
Conditions that support continued development include light wind shear, a large plume of moisture and very warm sea surface temperatures.
Jeff Lindner, Harris County Meteorologist
Interests along the lower Texas coast should monitor the progress of this system. Regardless of development, this system could bring locally heavy rains to southern Texas over the weekend.
More Rain for Houston Expected
In the northern hemisphere, low-pressure systems like this one rotate counterclockwise. So as the system heads toward Brownsville, it will spin moisture up along the Texas Gulf coast. That’s part of the reason why our rain chances for the next few days will remain high.
From Weather Live as of 12:40pm, 8/18/22.
As moisture from 99L spreads northward, it will interact with an incoming frontal boundary from the north and northwest early next week. That will also enhance rainfall chances.
Areas where Precipitable Water in atmosphere exceeds 1.5″. Precipitable waters are defined as the amount of water vapor in a column of air.Source: NWS Storm Prediction Center.
As of 6:34 pm Houston time, NHC has increased the chances of formation to 80% and has started referring to the storm in the Gulf as “potential tropical cyclone #4.” Hurricane Hunter aircraft this afternoon did not find closed circulation. The plane did find an area of 25-30kt winds well to the northeast of the weak wind field near the active thunderstorms. The system is morning NW at around 15mph. Lindner expects the storm to make landfall as a 45 mph tropical storm tomorrow evening near the Rio Grande.
For more information, including the expected arrival time of tropical storm force winds, warning cones, and wind-speed probabilities, click here.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/two_atl_5d0-2.png?fit=900%2C665&ssl=1665900adminadmin2022-08-19 13:26:202022-08-19 18:59:39Chances of Tropical Formation for 99L Increase to 80%
Most people think of Kingwood’s East End Park as a place to commune with nature. But it began as a natural, low-cost form of flood mitigation.
When Friendswood was building Kingwood, it toyed with the idea of building homes where the park now stands. Instead, it bequeathed the land to the Kingwood Service Association (KSA). KSA now maintains the property as a nature park for the benefit of all Kingwood residents. Leaving it natural also helps protect people from flooding.
Sometimes the best way to deal with the side effects of development is simply to preserve nature where flooding occurs most frequently. And it certainly occurs frequently along the East Fork of the San Jacinto River. In areas like these, parks provide a buffer. And that creates positive value while avoiding negative costs.
How Parks Create Positive Value
The main features offered in the 158-acre East End Park are tranquil, yet breathtaking views provided free of charge by Mother Nature. The park includes forests, wetlands, and natural meadows that provide food and habitat for wildlife. People often see families of deer munching on grass at the edge of the forests. Occasionally, visitors sight eagles, alligators, river otters, foxes, coyotes and bobcats.
KSA East End Park Poster. Photos by Bob Rehak.
Birders also find the park an urban wonderland. Forty-plus acres of tall grass meadows draw approximately 140 species of birds during the spring and fall migrations. Many of those are threatened or endangered. The Lake Houston Area Nature Club hosts birding tours here from September to May. They start at 7:30 AM from the parking lot at the east end of Kingwood Drive and usually last till about 10am.
Another major attraction of the park: spectacular sunrises most mornings.
East End Park at Sunrise by Dr. Charles Campbell.
Dr. Charles Campbell hikes several miles in the park each morning. He took the picture above not far from the main entrance at the east end of Kingwood Drive. He also took the one below at Otter Point.
Sunrise over Lake Houston from Kingwood’s East End Park at Otter Point. By Dr. Charles Campbell.
The park draws an estimated 100,000 visitors per year, but it rarely seems crowded because the visitors disperse among dense forests along 5+ miles of trails throughout the day.
East End Park is an exceptional amenity for Kingwood residents, gifted to all by a visionary developer. Was it totally selfless? Of course not. Nationally, research shows that proximity to parks can increase home values up to 20%. In short, people like parks.
Also Consider Cost Avoidance of Preservation
During Harvey, the entire park went underwater. Most of it also went underwater during the Tax Day, Memorial Day, and Imelda storms. Can you imagine what would have happened had Friendswood built homes here?
There would have been tens of millions of dollars in damages, losses to taxpayer-subsidized flood insurance, disaster relief funds, and the overhead of a bureaucracy to administer aid. Buyouts and demolition would have been required. Flood mitigation in the form of channels and detention basins would have cost tens of millions more. And all the positive values would have been lost.
But by just leaving it natural, we collectively saved all those personal and public expenses. We also created a beautiful “people magnet” that sustains home values instead of undermining them. Trail repair costs after Harvey totaled only $60,000.
That’s less than the cost to repair one average home flooded to a depth of a foot or more. And that’s the value of preservation – the natural, low-cost form of flood mitigation.
Sometimes we need to learn to just let nature be.
Posted by Bob Rehak on 8/18/22 with thanks to Dr. Charles Campbell
1815 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/Campbell-East-End-Park-Sunrise.jpg?fit=1200%2C675&ssl=16751200adminadmin2022-08-18 12:02:092022-08-18 14:41:05Preservation: A Natural, Low-Cost Form of Flood Mitigation
By this weekend, the second tropical wave in two weeks will make its way into the Gulf of Mexico. The National Hurricane Center (NHC) is monitoring a disturbance in the southwestern Caribbean. They predict it will track northwest across Central America and the Yucatan. Then it should emerge into the Gulf of Mexico later this week.
It’s too early to tell the exact track, timing or degree of development. That depends on many factors such as steering currents and frontal boundaries. But as of 7am Houston time on 8/16/22, NHC gives the disturbance a 20% chance of developing into a named storm within 5 days.
NHC says an area of low pressure could form on Friday. Gradual development of this system is possible while it moves northwestward over the southwestern Gulf of Mexico through the weekend.
15:20 Zulu time is 10:20 Houston time. Note the cloud formation in lower left over Nicaragua and Honduras.
Harris County Meteorologist Jeff Lindner says conditions will become increasing favorable for tropical cyclone development in the Bay of Campeche (the area with the yellow circle). He points to a frontal boundary dropping south toward the Texas coast late this week and says areas south of that boundary will become increasingly favorable for a low pressure system to develop along the axis of the tropical wave.
Weather Service Storm Prediction Center 3-Day Outlook shows front moving across southern plains on Friday.
Five years after Hurricane Harvey, the City of Houston’s Harvey Recovery Map shows that in the Lake Houston Area less than 100 families have received some form of financial assistance. That’s out of 16,000 homes and 3,300 businesses that flooded in the Lake Houston Area during Harvey.
9 families in Kingwood and 1 in Huffman received homebuyer assistance
78 families in Kingwood and 5 in Huffman received homeowner assistance for repairsor reconstruction
The City has yet to report any statistics for its Economic Recovery Program for Small Businesses
A second “disaster impact” map shows that in four Kingwood Census tracts, Harvey damaged more than 70% of the homes. The percent damaged exceeded 90% in two of those.
The Houston Housing and Community Development Department’s (HCDD) Hurricane Harvey Recovery Program still has hundreds of millions of dollars left to distribute. But with the exception of the City’s Multifamily Program, most other programs continue to stutter and stumble.
Citywide Statistics Not Much Better
Of the 96,410 homes flooded in Houston during Harvey, the City has submitted 1,426 single-family files to the GLO and received approval for 1,244 (789 for repair or reimbursement, and 455 for home buying assistance). The number approved equals 1.3% of homes damaged or destroyed.
Multifamily housing assistance is the one bright spot for HHCD. Out of the $450 million allocated to the program, the City has already spent or committed $355 million as of August 8, 2022. Seven projects have completed construction. Sixteen are under construction. Two are pending closing. And six are being underwritten.
Multifamily stats as of 8/8/22
Why the success for this one program? Corporations build multifamily complexes. Most of them can afford to hire people who pursue funding opportunities like this full time. They aren’t trying to get bids, track receipts and hold down regular jobs while repairing their homes from a disaster in their spare time.
Most of the feedback I have received is that flood victims without flood insurance who were living in travel trailers or with friends after Harvey took one of two paths. They paid for repairs out of pocket as they could afford them, or sold their homes “as is.”
Plus, the Homebuyer Assistance program has exhausted its funding and is closed. A red note at the top of the homepage of Recovery.HustonTX.gov says, “Due to … a pending decision on whether the City must return money that should go toward these critical programs and resources, we are no longer processing applications.” If more funding becomes available, those who previously applied will not be given preference.
A second red note says, “At this time, the City of Houston will continue assisting homeowners whose repairs and reconstructions were approved by the GLO prior to October 6, 2020. All other repair and reconstruction applications, including those approved after October 6, 2020, will be transferred to the GLO to complete the process.”
A final note says, “We appreciate your patience.”
Anything to Help Citizens
The good news: “The City of Houston Housing and Community Development Department is excited to announce beginning August 21st, we will be hosting open community office hours!” Every Wednesday, 1-4PM. “Walk-ins welcome, no appointment required!” If you still wish to apply.
Whoop-de-doo! Three hours a week! Five years after Harvey! Buried on a page that no one except reporters would take the time to find (at the bottom of the Transparency Page under the About Page). That’s really going above and beyond the call of duty to help citizens.
One can only wonder whether four hours a week – or putting the open-house notice on the home page – would help Houston recover faster.
Only one thing is certain: flood insurance beats the hope of disaster relief assistance.
To review the City’s July 2022 pipeline report that shows progress to date in several programs by stages, click here.
To review the compliance graphics for the City’s programs, click here.
Posted by Bob Rehak on 8/14/22
1811 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/Screen-Shot-2022-08-14-at-12.25.28-PM.png?fit=1612%2C962&ssl=19621612adminadmin2022-08-14 15:50:592022-08-14 22:46:29City’s Harvey Recovery Map Shows Lake Houston Area Has Received Little Assistance
A reader who visited a trade show recently in Las Vegas sent me several links to news stories about flash flooding there. 1.24 inches of rain caused widespread flooding, killed at least two people, and resulted in dozens of high water rescues!
His comment: “Imagine if those types of videos were in Houston – for less than two inches of rainfall. You can’t, because it doesn’t happen.”
Why Houston Doesn’t Flood On Two Inches
While HCFCD employees take a lot of heat every time someone floods, we should remember that it takes far more rain for people to flood here. There are several reasons for that.
First, Harris County formed a flood control district in 1937. Clark County, Nevada (Las Vegas) didn’t start its until 1985. So, we had an almost 50-year head start on them.
But sadly, some fast-growing counties around Harris County STILL don’t have flood control districts! (We’ll save that discussion for the next legislative session.)
Second, our topography is different. Because Harris County is so flat, rainfall spreads out and starts soaking into the ground before flooding starts. Rainfall in Las Vegas is funneled by the rugged landscape. It picks up velocity, so it doesn’t have time to soak in. Concentrated rainfall turns into flash flooding. The Las Vegas Wash funnels a 1,879 square mile watershed toward a metro area of 2.29 million people.
I was almost killed by a flash flood in Tucson once. While hiking along a stream bed with friends in the desert, we saw rain in the distant mountains. They immediately suggested moving to higher ground. Minutes later, a wall of water 6-8 feet high came boiling down that stream bed!
Atlas-14 rainfall probabilities for northern Harris County now form the basis for building codes and flood-mitigation projects.
In other words, we build things to withstand more rain in a day than Las Vegas receives in FOUR YEARS.
That takes some talent. Especially when surrounding areas send ever-increasing amounts of floodwater downstream because of lack of comparable controls upstream. And that could be why flood control districts around the country try to recruit talented HCFCD employees.
Despite our occasional frustrations, we should never forget: They stand between us and disaster.
Posted by Bob Rehak on 8/13/2022
1810 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/20220813-Screen-Shot-2022-08-13-at-12.03.28-PM.jpg?fit=1200%2C675&ssl=16751200adminadmin2022-08-13 12:53:152022-08-13 19:42:38Giving Thanks to the Women and Men of Harris County Flood Control
The National Hurricane Center (NHC) issued a tropical weather outlook today that shows a 10% chance of tropical formation in the Gulf. This is your “heads up.” Hurricane season is ramping up.
NHC will provide an update on chances for development later this evening, but models show growing support that a tropical depression or weak tropical storm is possible along the middle or lower TX coast by Sunday. The system will then moving inland over south Texas late Sunday into Monday, according to Jeff Lindner, Harris County’s meteorologist.
Latest Satellite Imagery
Here’s what the Gulf looks like on satellite Friday evening. The system will track W to WSW over 85-90 degree waters toward the mid- or lower-Texas coast on Sunday.
4:51 PM Houston DST
Currently, disorganized showers and thunderstorms over the north-central Gulf of Mexico are associated with an area of low pressure centered just offshore of the southern coast of Louisiana. There’s no tropical formation yet. But that could change.
As of 2PM EDT today, NHC listed the formation chance through:
48 hours…low…10 percent.
5 days…low…10 percent.
Rainfall Potential
Regardless of development, locally heavy rains are possible along portions of the Texas coast through the weekend. For more information about the potential for heavy rainfall, please see the National Weather Service site and the Weather Prediction Center.
Decent rain chances exist for the next three days, especially along the coastline south of I-10.
Jeff Lindner, Harris County’s meteorologist says, he expects most of the shower and thunderstorm development associated with this low pressure system to happen near the coast and offshore. He expects lesser chances inland to the north as high pressure and drier air begins to build southward from the northeast.
Forecasters use a measurement called PWS (Precipitable Waters) to predict amounts of rainfall. PWS measures the amount of water vapor in a column of air. This weekend with PWS of 2.2-2.3 inches and possible cell training, Lindner warns that a quick 2-3 inches of rainfall in less than an hour will be possible. Even though grounds are dry and should be able to handle the rainfall, some street flooding will be possible with those rates.
No River Flooding Expected
However, National Weather Service expects no significant river flooding in the next five days.
Tide Report
According to Lindner, tides are already elevated along the coast due to the full moon. Easterly and southeasterly low-level winds on the north side of the low may bump seas up a bit over the weekend and push tides a little higher. He expects water to be way up on the beaches at high tides over the weekend.
Monitor forecasts closely over the weekend for any changes.
Posted by Bob Rehak on 8/12/2022
1809 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/1000x1000.jpg?fit=1000%2C1000&ssl=110001000adminadmin2022-08-12 17:29:382022-08-12 17:30:40Slight Chance of Tropical Formation In Gulf This Weekend
Quick, somebody call Ripley. Against all odds, water appears to be flowing uphill at the Laurel Springs RV Resort.
Note the pond to the left of the detention pond near the tree line. A sharp drop off exists below the bank of the detention pond, toward Edgewater Park on the left. Now see closeup below.
The only apparent source for water in the circle is the pond on the left. But that’s below the water in the circle.
Is this an optical delusion? Or could something else be going on here? Could water actually be leaking through the dike?
Location of Buried Pipe
Back in January, contractors dug a trench through the dike and released the contents of the resort’s detention pond into Edgewater Park.
Silty stormwater being discharged into the wetlands of Harris County’s Edgewater Park below the RV resort. January 2022.
Later, a contractor told me his company removed the pipe. But I couldn’t find a single nearby resident who saw them do it. Subsequently, I’ve noticed water apparently leaking from the detention pond into the park after several rains…at this same spot! See below.
May 2022. Exact location shown in photos above.
So one possible explanation for this violation of the law of gravity could be that the pipe remains buried in the dike and water leaks through it. But I just can’t believe a contractor would lie to me!
If the pipe remains in the dike, that would seem to violate the owner’s construction permit. It says, in big red letters, “Stormwater Runoff Shall NOT Cross Property Lines.” I can’t believe the developer would violate permit terms either!
It’s hard being a small business owner these days. Do you violate Newton’s Law of Gravity or City law? Given a choice, it might be cheaper to go with Newton. So all things considered, I guess they figured out a way to get water flowing uphill. I’ve heard the owners are marketing geniuses.
I’m sure vacationers would drive their RVs from all across North America to see water flow uphill. Imagine the postcard sales!
Mysterious Black Spots Reappear
But that’s not the only possible tourist attraction. You’ve heard of people getting blood from a stone. At the Laurel Springs RV Resort, oil appears to simply ooze from the ground. Move over Beverly Hillbillies!
Looking North from over Edgewater Park. Note dark areas in red circle and see magnified image below.Photo taken 8/11/22.From a legal height, I shot straight down and photographed an oily sheen on the black spots.
This is the same location where I previously photographed contractors covering up black spots on several occasions. See one below.
Mysterious black spots in Laurel Springs RV Resort Detention Pond on March 10, 2022. Note bulldozer tracks.
Never ones to pass up a marketing opportunity, the RV resort owners reportedly hope to hire Max Baer, Jr., the last surviving member from the classic Beverly Hillbillies sitcom from the 1960s and 70s. Rumor has it, they want the 83-year-old Baer, who played Jethro, to be the first person through the gates at the grand opening. He would reportedly pass out samples of the oily substance so that RV owners across America can live the dream and tell their grandchildren how they struck oil while vacationing in Texas.
Concrete Galore
In another feat of marketing genius, the developer convinced the City of Houston permitting people that one third of the property would NOT be impervious cover, i.e., concrete.
The developer is not yet done with pouring concrete. But it appears as if it will cover a lot more than 2/3rds of the site.
Will one third really be pervious?
By the way, according Section 9.1.04.O of the City’s Infrastructure Design Manual, detention ponds count as 100% impervious cover regardless of whether they have wet or dry bottoms. So the pond doesn’t count toward the one-third – just those skinny slots between RV parking spaces. And does it look like they add up to seven acres!?
It looks like Harry Houdini would have a hard time squeezing between the narrower ones. Of course, Houdini died in the 1920s. So how will they divert attention from this one? The developer reportedly wants to hire David Blaine, reputed to be the world’s greatest living escape artist, to appear at the grand opening. Blaine will show anyone who complains about the tight parking spots how to squeeze into his/her RV.
I can’t wait for the star-studded grand opening when I get to see water flowing uphill, Jethro passing out oil, and City inspectors lining up for David Blaine’s autograph.
Posted by Bob Rehak on 8/11/2022
1808 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/20220811-DJI_0320-2-copy.jpg?fit=1200%2C799&ssl=17991200adminadmin2022-08-11 19:23:462022-08-11 23:06:37Water Flowing Uphill at Laurel Springs RV Resort
When I first started exploring the forests north of Houston 40 years ago, I thought they were among the prettiest places in Texas.
The towering pines had a quiet beauty. They wrapped you in a blanket of solitude. Surrounded you with silence. Calmed the soul. Enabled a retreat from workday worries into a world of wonder.
Here, you could reconnect with the roots of life. Relax. Restore. Renew. Right outside your back door. I just had to live here! But a million other people had the same dream.
16 Lanes Later
The dream became so successful that we paved 16 lanes to it.
Looking North at I-69 and Kingwood from over the West Fork San Jacinto
The same thing happened along I-45. As one development after another sprang up, we found ourselves destroying what attracted us here.
The Pursuit of Loneliness
As I reflected on this, it reminded me of a book I read in 1970, The Pursuit of Loneliness by Phillip Slater. For thousands of years, Slater said, to be civilized meant to be citified. We love all the benefits of living in a city (such as jobs, shopping, medical care, and events), but we dream of a place in the country that lets us escape. So we buy some acreage, use up hours each day commuting. And wake up years later only to find that millions of us have collectively destroyed the very lifestyle we fought so hard to attain.
Here’s what I found from four hundred feet up as I flew last month from I-45 to I-69 down the San Jacinto West Fork in a helicopter – 20 square miles of sand mines in a 20 mile reach of the river – carved out of one of the prettiest places in Texas. Unfortunately, this isn’t the only such stretch of river like this in the region.
All that opaque blue water isn’t what you’d find on a Caribbean island. It’s likely loaded with chlorides or cyanobacteria.
Dreams Built on Sand
Ironically, it takes sand to make concrete. And it takes concrete to build 16 lanes to your dream home. It might be worth it when you live at the end of the road and they take the sand from someplace else. You can still enjoy the dream.
But when the 16 lanes go 20 miles beyond you, when someone tears up YOUR forest to get the sand, and destroys the beauty you built your dream around, it makes you wonder whether there is a better way.
Can we find the sand somewhere else? Can we define rules for mining that preserve our collective dream, perhaps by repurposing the mines after we have exhausted them? Can we give developers an incentive to preserve trees instead of clearcutting them? Hope springs eternal, as the poets say. Another legislative session starts in January. Stranger things have happened.
Posted by Bob Rehak on 8/10/22
1807 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/20220722-RJR_0349.jpg?fit=1200%2C800&ssl=18001200adminadmin2022-08-10 17:37:332022-08-11 16:27:30One of the Prettiest Places in Texas
On 7/22/22, I photographed two new developments at different stages of completion east of Huffman-Cleveland Road and south of the Grand Parkway. Both are being carved out of a 3,738-ac tract owned by LH Ranch LTD.
A third part of that tract, west of Huffman-Cleveland Road, is in the planning stages and submitting plats for approval.
General Location
The first two developments are immediately east of Huffman-Cleveland Road and south of Meyer Road. See red area below.
Red outlined area contains the two new developments.The third area is to the west (left) of the red box.
One of the new developments will become a “lagoon community” called Saint Tropez. Another will become a residential community called Los Pinos. The third will also become a residential community.
Saint Tropez
Megatel Homes has begun clearing land for what it says will become a $2 billion lagoon community spanning 1,000 acres.
Looking SW from over Meyer Road at the first part of what will become Saint Tropez.
According to Megatel, the development will eventually feature 4,500 homes, an enormous manmade lagoon with white sand beaches, paddle-boarding, kayaking, a swim-up bar, surf simulator, a water slide tower, a playground, cabanas, soundstage, splash park, and more.
An entertainment district will offer a restaurant, bar, teen arcade, bowling alley, and a children’s immersive indoor play area. That will certainly change the character of the rural Huffman area.
The development will feature both single and multi-family housing. Single-family homes will range in size from 1,500 square feet to 4,000 square feet and sell for between $350,000 to $700,000 each.
Full construction plans and a drainage analysis are not yet available. At this time, the Harris County Engineering Department has only issued a permit for clearing the land, but it shows a general layout.
Plan submitted to Harris County Engineering to obtain clearing permit. Intersection of Meyer Rd. and FM2100 in upper left.
Los Pinos
South of Saint Tropez, the second development is much further along. For it, I have obtained both construction plans and a drainage analysis via a FOIA Request.
Looking SE from over FM 2100. Note the large, linear detention basin in the foreground running diagonally through the frame.
Drainage Features
Phase One of the 130-acre Los Pinos Project will have approximately 250 single-family residential lots. The 1/3rd-acre lots will have about 30% impervious cover.
Plans claim that the total detention storage will exceed Harris County Flood Control District’s (HCFCD) minimum storage requirements. They require 270.4 acre feet, but the developer will provide 366.3 – 26% more.
Phase One sits in the FEMA’s unshaded X zone (higher than the 500-year flood plain). So there is no requirement for floodplain mitigation.
Preston Hydrologic, Inc., which conducted the drainage analysis, says, “The proposed detention basin will reduce the maximum sheet flow depths downstream of the development, for storm events up to and including the 1% AEP storm.” AEP means annual exceedance probability. And 1% refers to a 100-year storm.
The tract drains to Key Gully and two unnamed tributaries within the Luce Bayou watershed. This development falls outside Houston’s city limits in unincorporated Harris County.
Looking east from over FM 2100. Note a second large linear detention pond on the right bracketing the development.
Water in this area naturally flows toward the southeast where it enters Luce Bayou. The detention ponds that bracket the development are designed to contain rain falling on the development and water trying to flow across it.
Map from Preston Hydrologic’s drainage analysisshows layout of detention basins.
Six interconnected, dry-bottom detention basins will mitigate the impacts of development, according to hydrologists. The lots in proposed Phase 1 will drain into Ponds 2 and 6. Ponds 1, 3, 4, and 5 will intercept runoff from undeveloped land.
Peak flow estimate indicates ponds should hold a 100-year rainfalland cut peak outflow roughly in half(red vs. blue curve)
Claims No Adverse Impact
Hydrologists claim the development will cause “no adverse impacts” compared to the pre-project drainage conditions of the receiving streams in the Luce Bayou watershed. That includes downstream properties within the City of Houston.
They also estimate that overlandsheet flow will not cause any adverse impacts downstream of the project site. In fact, the hydrologists claim that the proposed project will reduce peak flow rates and runoff volumes to areas downstream. That, they say, will result in reduced ponding depths in the Huffman Hills subdivision and adjacent properties.
Small Part of Future Development
The 130-acre Los Pinos Phase One tract represents only 0.34% of the larger LH Ranch Tract from which it is carved. The hydrologists caution that future phases will require future studies of their own. They indicate that future uses of the LH Ranch tract may include additional single-family residential development, commercial development, and a wetlands mitigation bank.
The mitigation bank proposal showed that 25% of the LH Ranch tract would be set aside for mitigation.
The LH Ranch tract bridges two watersheds. The western portion drains to the East Fork. The eastern portion drains to Luce Bayou. Both eventually drain into Lake Houston. Much of the land was originally wetlands.
Image from same general area taken on January 2021 when tree canopy did not obscure ground.Note standing water.
Preston Hydrologic believes that the increased runoff from Los Pinos Phase One will not increase erosion in Key Gully. They base that opinion on three factors: a USGS estimate of soil-erosion potential in the area, reduced peak flow, and slower water velocity at the peak.
Potential Problems
Section 5.3 of the drainage analysis cites an inventory of potential problems. Among them: Colony Ridge. Preston’s report says, “Currently, a large developing area adjacent to the Harris-Liberty County line may create problems for water quantity and quality. This development is large-lot rural and uses underground septic systems located in the effective floodplain area of Luce Bayou. Additionally, it is possible that inadequate drainage infrastructure is being provided in the area, which could lead to a possible increase of floodwater peak flow rates downstream in Harris County.”
West of FM 2100, LH Ranch LTD and Friendswood Development applied to the Houston Planning Commission for plat approval of a 927-acre parcel on 8/4/22. This parcel is immediately west of the two projects discussed above. It drains into the East Fork on the left edge of the map below.
No further details are available at this time. I will watch it closely in the future months. One thing is clear: Huffman will never be the same.
Posted by Bob Rehak on 8/9/22
1806 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/08/20220722-RJR_0726.jpg?fit=1200%2C800&ssl=18001200adminadmin2022-08-09 14:25:202022-09-19 11:50:273738-Acre Property Developing Near Huffman
Almost $200 million of additional studies, analysis, models and mapping
$27.9 billion in projects.
The projects spread throughout the entire watershed. But here, I’ll focus on those in the northern portion of Harris and the southern portion of Montgomery Counties for brevity.
Halls Bayou
The Flood Planning Group recommends five projects in Halls Bayou totaling $99.65 million, all in collaboration with Harris County Flood Control District (HCFCD). They include:
Channel conveyance Improvements on several tributaries
Stormwater detention improvements near Hardy West
Stormwater detention and channel conveyance improvements along the main stem.
These projects had a positive 1.46 Benefit/Cost Ratio PLUS additional community benefits hard to quantify. They would remove the floodplain from more than 3,000 structures and benefit more than 9,300 people. See pages 5-14 through 5-16.
White Oak Bayou
The Flood Planning Group recommends five channel improvement and detention basin projects for $120 million along White Oak Bayou. The flood planning group determined a benefit/cost ratio of .80 for these projects, meaning costs exceeded benefits. Regardless, they feel there are many community benefits that cannot be quantified. They include removing flood risk from seven miles of roads. See pages 5-15 through 5/18.
Greens Bayou
Greens Bayou would receive $120 million of improvements (construction costs only). They include projects in Fountainview Sections 1 & 2, Castlewood Sections 3 & 4, North Forest, Mid-Reach Greens, Parkland Estates, and Humble Road Place.
A bypass channel under the railroad that parallels US 59 could reduce upstream water surface elevations during extreme events. And a mitigation basin downstream would absorb any adverse impacts in Parkland Estates and Humble Road Place from the bypass channel.
The BCR for all Greens Bayou improvements equals 2.13, meaning benefits double costs. More than 20,000 individuals and 2,000 structures would benefit. See pages 5-18 through 5-20.
San Jacinto River
The Flood Planning Group recommends numerous projects associated with the East and West Forks of the San Jacinto River and their tributaries. It based these recommendations on the San Jacinto River Regional Watershed Master Drainage Plan and a 2018 LiDAR study. See pages 5-21 through 5-31.
Caney Creek
Recommendations include channelizing part of Caney Creek and offsetting that with two dry-dam detention basins: one at FM1097 and the other at SH105. Together, they would store more than 40,000 acre feet of stormwater. That’s enough to hold a foot of stormwater falling across 62.5 square miles! Channelization would occur near the confluence of Caney Creek with the East Fork. That’s near Lake Houston and East End Parks. The projects would remove 42 miles of roadway and 2,422 structures from the 1% annual chance floodplain.
East Fork
A 48-ft tall concrete dam would create a 1.60-mile-long earthen impoundment that captures runoff from Winters Bayou. The dry dam would have five reinforced 10×10 concrete culverts and twin 300′ backup spillways. It would cover almost 2,500 acres and hold 45,000 acre feet of floodwater. That’s enough to hold a foot of stormwater falling over 28.8 square miles.
Lake Creek
Lake Creek would receive some channelization and two dry-dam detention basins holding 37,250 acre feet of storage, enough to hold a foot of stormwater falling over 58 square miles.
Peach Creek
Recommendations also call for partial channelization and two dry-dam detention basins along Peach Creek.
The Walker Detention basin would occupy 1,200 acres, hold 36,000 acre feet of stormwater, and cost $200 million.
The SH105 Detention basin would occupy 3,000 acres, hold 36,000 acre feet, and cost $400 million.
The total 72,000 acre feet of capacity would hold a foot of stormwater falling over 112.5 square miles.
Spring Creek
This project would channelize 15.7 miles of stream at I-45 and through the Woodlands. It would also create two detention basins on Birch and Walnut Creek tributaries to help reduce flood risk downstream. Together, the projects would create more than 35,000 acre feet of floodwater storage capacity, enough to hold a foot of rain falling over 54.8 square miles. The report did not break out the costs.
West Fork
The Flood Planning Group recommends widening and channelizing 5.7 miles of the West Fork near Highway 242. They would create 12,400 acre feet of mitigation storage by widening the river to 750 feet and creating a 2-foot bench above the stream bed. That would involve shaving down the floodplain to 2 feet above the waterline.
Farther downstream, in the Kingwood Area, they would also increase conveyance by widening a 5-mile-long stretch of the West Fork with 3,500-foot wide of benching. This project would require 923 acre-feet of mitigation storage
That would increase total floodwater storage in both locations by 13,423 feet – enough to hold a foot of rain falling across 20.9 square miles.
Other portions of the recommendations stress the need for additional strategies. They include but are not limited to:
A regional approach to flood mitigation
Floodplain preservation
Natural solutions
Minimum building setbacks
More stringent building codes
Better drainage regulations
Uniform regulations across the watershed
Adoption of standards for determining “no adverse impact”
Also note, that these recommendations would take decades to implement and that many would need to be implemented in a specific order. For instance, the State would need to build detention upstream before widening channels downstream. One helps mitigate the other. Without that, you could help people upstream, but hurt people downstream. That flies in the face of HCFCD principles.
