Tag Archive for: mouth bar

February East Fork Mouth Bar Dredging Update

Since last month, dredgers have removed one island and have started on another in the massive complex of sand bars laid down during Harvey and Imelda on the San Jacinto East Fork where it meets Lake Houston.

Current Location

Another island in the San Jacinto East Fork Mouth Bar complex.
Another island in the San Jacinto East Fork Mouth Bar complex is being dredged away. Photo taken on Sunday afternoon, 2/20/22. Looking downstream toward Lake Houston.

The sand bar already eliminated was toward the top and left side of the frame above. It stretched almost 2000 feet.

Now dredgers are focusing on the giant bar in the middle above.

Mouth Bar Complex in 2020 Before Start of Dredging

The shot below, taken from the opposite direction, helps put things in perspective.

East Fork Mouth Bar
Looking upstream at the East Fork Mouth Bar complex in March 2020 before dredging. The bar dredgers already eliminated is the bright white one in the foreground. Now they’re working on the one farther upriver and to the left.

More Current Shots Taken Today

East Fork Mouth Bar Complex
Looking NE at dredging in the East Fork Mouth Bar Complex. It looks like they may have started here and moved elsewhere for some reason. Photo taken 2/20/22.
This shot more than the others, gives one a feeling for the immensity of the task.

Long Range Dredging Plan

The City of Houston’s purchasing website does not indicate whether the City has yet awarded the project to develop a long range dredging plan. Last month, the purchasing agent for the City, Bridget Cormier, stated that “The City has not yet made a decision, nor a recommendation for award yet.” She explained, “We are still in the evaluation phase and have requested additional information from suppliers that moved forward in the process.” 

It took three months just for contractors to dredge their way through the Royal Shores channel to get to East Fork (July, August, September 2021). East Fork dredging started in October last year. Spoils are currently being ferried back to land south of the West Fork, opposite River Grove Park. There it dries before TexDoT hauls it away for use in roadbuilding.

Posted by Bob Rehak on 2/20/2022

1636 Days since Hurricane Harvey

Above-Water Portion of Mouth Bar Could Be Gone by Christmas

At the current rate that crews are removing sand from the West Fork San Jacinto Mouth Bar, the remainder of the above-water portion of this once-behemoth sand bar could be gone by Christmas. See the two pictures below. The first taken after Harvey and the second taken today.

These two shots show the West Fork mouth bar two weeks after Harvey and todaymore than three years later.

Much Yet to Dredge

Of course, even when the above water portion of the Mouth Bar is removed, that will still leave a huge portion below the surface. However, all progress is welcome.

Like an iceberg, most of a sand bar exists below the waterline. Photo taken 10/26/2020. I can’t say with certainty that this is submerged sand, or water stirred up by dredging. It seems too uniform to be the latter. Compare the picture below looking toward the WLHP bridge from a slightly different position and note how irregular the stirred-up sediment looks. Also note that the picture above was taken upstream from the current dredging.

At the start of October, the above-water (sub-aerial) extent of the mouth bar was down to the width of one excavator. Two excavators are now working toward the middle from each end. See below.

Looking WNW toward the West Lake Houston Parkway Bridge and Kings Harbor. Taken 10/26/2020.
From the wet mark on this excavator’s arm, it looks as though they are excavating up to 10 feet below the waterline. The 10-foot estimate closely agrees with the profile chart below. Taken 10/26/2020.

Like an Iceberg, Most of a Sand Bar Exists Below Water

That’s significant progress given what we started with. But much sand remains below the surface.

Tim Garfield and RD Kissling, two leading geologists now retired from one of the world’s largest oil companies, mapped the depth of the river using sonar and depth poles. They found an underwater plateau exists in this region of the river. See chart below.

The blue line represents the water surface. The gold line indicates the deepest part of the channel as you move downstream from the WLHP bridge to the FM1960 bridge. Numbers on the left scale indicate water depth. Numbers on the bottom scale indicate distance in feet downstream from the WLHP bridge.

Plans for Next Phase Still Not Revealed

FEMA has approved dredging another million cubic yards. And Dan Huberty’s amendment to SB500 in the last legislature dedicated $30 million for dredging the West Fork Mouth Bar. The City is drawing up plans, but they have not been announced yet. The last time I talked to Stephen Costello about this, he said the City was leaning toward dredging a channel somewhere south of the mouth bar. But many details remained to be worked out, such as:

  • Method of dredging (hydraulic vs. mechanical)
  • Exact location
  • Channel width
  • Finding qualified contractors
  • Bidding
  • Determining a suitable placement area, etc.

More news when its available.

Posted by Bob Rehak on 10/26/2020

1154 Days after 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.

Two Top Geologists Suggest Mouth Bar Dredging Strategy

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.


The Army Corps of Engineers dredged from River Grove Park to Kings Harbor in 2018 and 2019, removing approximately 1.8 million cubic yards. After a contentious battle with the City, the Corps then agreed to remove another 500,000 cubic yards south of the Mouth Bar in the Spring and Summer of 2019. This year, the City of Houston started removing the portion of the mouth bar that remained above water; they are still working on it (see above). Recently, FEMA agreed to remove another million cubic yards. And waiting in the wings is another $30 million that can be applied to additional dredging. State Representative Dan Huberty secured that money in the last legislature.

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.

Note abrupt drop north of FM1960 Causeway.

Recommend Following Original Channel

The cross-section graph of the river bed above represents the deepest part of the river. On either side of that centerline, the riverbed rises to two or three feet below the surface of the water. The centerline closely follows the paleo (original) channel of the river before the Lake Houston dam was built.

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 Kissling that 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.

Read Garfield and Kissling’s full study, Evaluating West Lake Houston Bathymetry, Dredging Status and Recommendations.

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

Approximately 1,000 Plaintiffs File Suit Against Sand Mines in Harvey Flooding

On February 20th of this year, approximately 1,000 plaintiffs filed a 118-page lawsuit against 55 sand mining companies in the San Jacinto River Basin. Plaintiffs allege that the miners harmed them by decreasing the capacity and depth of Lake Houston and its tributaries by wrongfully discharging and negligently allowing the release of materials into waterways. That reduction of capacity, they say, contributed to flooding their homes and businesses.

Western half of LMI River Road mine in floodway and flood plain of San Jacinto West Fork. Note also in foreground how the mine undermined five pipelines carrying highly volatile liquids.


To support their claims (¶613), plaintiffs cite violations of Texas Commission on Environmental Quality (TCEQ) regulations and the U.S. Clean Water Act. They claim:

  • Excessive, unauthorized discharge of silt into waterways
  • Failure to:
    • Obtain stormwater discharge permits
    • Prevent unauthorized discharges
    • Minimize generation of dust and off-site tracking

Past and Present Activities Cited

Some defendants, they say, operated above permit limits and others operated without any permits at all (¶614).

Plaintiffs say (¶615) that defendants have operated immediately adjacent to various waterways and in the flood plain, clearcutting all vegetation, and digging pits within feet of the riverbanks. Thus, there are no real barriers between mines and the rivers, they claim. Further, they allege that defendants have no plans in place for protection and preservation of their pits and loose sand during flood events, which occur frequently.

Then Came Harvey

Hurricane Harvey, they say, inundated mines and “thousands of acres of sand washed downstream, clogging the rivers and lakes, resulting in flood waters moving outside the banks and outside the flood plain, causing hundreds of millions of dollars in damages.”

Washed out road INSIDE sand mine during Harvey.
Submerged sand mines in the floodway of the San Jacinto West Fork during Hurricane Harvey in 2017

Alleged Violations of Water Code

The defendants had a duty to implement procedures to reduce the discharge of sediment into waterways, but did not, according to the plaintiffs. Thus, the proximate cause of plaintiffs’ injuries involved negligence and negligence per se. Defendants allegedly breached their duties under sections 11.086, 26.039, and 26.121 of the Texas Water Code, thus causing flooding and damage to plaintiffs’ property.

To prove negligence, personal injury plaintiffs must show that the defendants’ conduct fell below the applicable standard of care and that their actions were the actual and proximate cause of harm. 

In cases of negligence per se, defendants’ actions are assumed to be unreasonable if the conduct violates an applicable rule, regulation, or statute. That’s why lawyers cite the Texas Water Code, plus TCEQ and EPA regulations.

  • 11.086 of the Texas Water Code provides that no person impound the natural flow of surface waters, or permit impounding to continue, in a manner that damages property of another by the overflow of the water diverted or impounded.
  • 26.039 specifies that mine operators must notify the TCEQ of accidental discharges or spills that cause or may cause pollution as soon as possible.
  • 26.121 prohibits discharge of pollutants. Both the EPA and TCEQ consider sediment a pollutant.

Specific Omissions

Specific omissions, say the plaintiffs, include failing to:

  • Locate sand mines outside of floodways
  • Increase the width of dikes
  • Decrease the slope of dikes
  • Control erosion with vegetation
  • Replant areas not actively being mined
  • Protect stockpiles from flooding
  • Mine only above the deepest part of the river
Flooding from Hurricane Harvey in Kingwood’s Town Center where 100% of businesses were disrupted, most for approximately a year. Some still have not reopened. Photo by John Knoezer.

Nuisance Claim

The plaintiffs also allege nuisance. Under Texas law, nuisance refers to a type of legal injustice involving interference with the use and enjoyment of property. Specifically, plaintiffs say that the defendants’ negligent conduct caused paintiffs’ flooding, thus depriving them of the use of their homes.

Complaint against Forestar by Barrington Residents

On page 108, a subset of plaintiffs (those who live in the Barrington), lodge a complaint against Forestar (USA) Real Estate Group Inc. They allege that Forestar developed, marketed and sold homes in the subdivision without any standards for determining the elevation of a house relative to flood risk.

The Long Ride to Safety During Harvey. Barrington Photo by Julie Yandell.
The Long Ride to Safety During Harvey. Barrington Photo by Julie Yandell.

“Despite having actual knowledge of the possibility of flooding in the Barrington Subdivision, Forestar did not advise homebuyers to purchase flood insurance,” says the complaint (¶640). “Nor did Forestar advise the residents of the Barrington Subdivision of its location on a floodplain, or that their elevations were changed due to lots being filled with dirt” when residents purchased homes.

Nevertheless, the complaint continues (¶643), homes were built at an “unreasonably low” elevation, given their location near the West Fork San Jacinto. “Forestar knew, or should have known, that houses needed to be built at an elevation adequate to prevent and/or reduce the likelihood of flooding.”

Clean out after Harvey in the Barrington. By Joy Dominique.
Clean out after Harvey in the Barrington. By Joy Dominique.

Damages Alleged

Plaintiffs allege damages that include:

  • Cost of repairs to real property
  • Cost of replacing personal property
  • Lost of use of real and personal property
  • Diminution of market value
  • Loss of income, business income, profits and business equipment
  • Loss of good will and reputation
  • Consequential costs, such as loss of time from work and alternate living expenses
  • Mental anguish
  • Pre- and post-judgement interest
  • Court costs

Conscious Indifference and Gross Negligence

¶658 asserts that the conduct of all defendants (sand mines and Forestar) qualifies as gross negligence under Texas law. The plaintiffs say that the defendants acts of omission involved an extreme degree of risk, considering the probability and magnitude of harm to others. Plus, “Defendants had actual subjective awareness of the risk involved in the above described acts or omissions, but nevertheless proceeded with conscious indifference to the rights, safety and welfare of plaintiffs and others.”

Where Case Stands

129th District Court Judge Michael Gomez signed a docket control order on 2/28/2020 that calls for:

  • All parties in the suit to be added and served with notice by 8/19/2020
  • Close of pleadings and start of mediation on 12/16/2020
  • End of discovery on 1/15/2021
  • All motions and pleas heard by 1/15/2021
  • Trial, if necessary, on 2/15/2021

To date, there have been several motions to transfer venue, dismiss the case, and change the judge.

Only Triple PG Sand Development, LLC has filed an answer to the plaintiffs’ claims; the company filed a general denial.

In a separate case, the Attorney General of Texas is suing Triple PG for failing to prevent and repair breaches in dikes that resulted in repeated unauthorized discharges of process wastewater and sediment into Caney Creek. Caney Creek joins the East Fork San Jacinto just downstream from Triple PG. Triple PG currently operates under an injunction that bars it from dredging.

Breach of Triple PG mine into Caney Creek and the headwaters of Lake Houston

Editorial Opinion

If successful, this case may force sand mines to operate more responsibly, now and in the future. For instance, it might force them to move farther back from rivers and out of floodways. Having taken thousands of photos of leaking sand mines from the air since Harvey, in my opinion, that might benefit everyone, not just the plaintiffs.

Giant sand bar at the mouth of the West Fork which backed water up through much of Kingwood, Atascocita and Humble.
Mouth bar on the East Fork San Jacinto grew by thousands of feet during Harvey and Imelda. Downstream from Triple PG and Texas Concrete Mines.

To read the entire lawsuit, click here.

Posted by Bob Rehak on August 2, 2020

1069 Days after 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.

West Fork Mouth Bar Getting Snack Sized

Mechanical dredging is slowly but surely downsizing the San Jacinto West Fork Mouth Bar. It’s still about a billion times larger than a snack-sized McDonald’s Oreo McFlurry, but it’s a vast improvement over what it was. It now appears to be about one third of its size in January when most people would have called it super sized.

A Sisyphean Task

Snack-sized puns aside, the job is a Sisyphean task. For those not familiar with the term, Sisyphus was a figure from Greek mythology who angered Zeus. Zeus sentenced him to rolling a boulder up a hill for the rest of eternity only for it to roll back down again every time he got near the top.

Historians and storytellers see many morals in the tale. Be persistent. Work hard. Never give up.

And so it is with those three lonely excavators working on giant sand bar at the mouth of the West Fork where it meets Lake Houston.

Day in and day out, they remove one bucketful at a time. Six months after they started, much of the above-water portion of the sand bar has now been removed. But they still haven’t started to address the matter of cutting a channel that connects the dredged portion of the river with the lake.

Meanwhile, more sand and silt comes down river with every storm.

Comparing Post-Harvey with Recent Photos

Still, if you compare post-Harvey photos with photos taken recently, you can see progress.

Dredgers are slowly reducing the dam behind the dam.

Looking south toward FM1960 in 2017.
Looking south today. Little length has been removed, but the width is about a third of what it was after Harvey. Photo taken 6/16/2020.

The dredgers keep nibbling the south edge of the bar, taking row after row of sand, much like eating an ear of corn.

Looking west, upstream, from eastern end. Photo 7/5/2020.
Western tip of bar is now only a little wider than the tracks of one excavator. 7/5/2020.
Looking east at sunrise on 7/5/2020. Note FM1960 bridge in the extreme upper right.

In the next few months, they may run out of room to maneuver on the bar.

Survey Boat Spotted on Lake Last Week

Residents recently reported seeing a survey boat out on Lake Houston. That’s a good sign. It says that the City, County and State are now looking at what should come next with the $30 million that State Rep. Dan Huberty got the legislature to commit last year as an amendment to SB500. Harris County Flood Control also committed $10 million to dredging in the 2018 flood bond fund.

The City is currently funding the mechanical dredging with $6 million left over FEMA disaster recovery funds. Those should be running out soon if they haven’t already.

To my knowledge, no one has yet addressed the issue of long-term maintenance dredging, although everyone acknowledges the need for it. That river just keeps on bringing sediment.

Posted by Bob Rehak on 7/6/2020

1042 Days after Hurricane Harvey

Buzzing The Mouth Bar: Low Altitude Flyover at 30 MPH Takes 1 Minute 9 Seconds

It’s hard to get a feeling for the enormity of the West Fork mouth bar in a still photo. Something more than half a mile long is reduced to 1200 pixels. That fundamentally alters the scale between nature and humans. Instead of being a thousand times bigger, it’s a hundred times smaller. That does not produce the same emotional impact. It’s like looking at a picture of a mountain instead of standing at the base of one and feeling dwarfed as you look up.

Video Comes Closer to Capturing Imensity

However, tonight, at sunset, I flew a drone over mouth bar and captured the entire flight on video. At 30 miles per hour, it took 1 minute and 9 seconds to get from one end to the other.

The rapidly vanishing San Jacinto West Fork mouth bar. Mechanical dredging reduces the size a little more every day.
Looking south from Scenic Shores in King’s Point across mouth bar toward FM1960 Causeway downriver.
Looking west toward West Lake Houston Parkway.
Excavators working western tip of mouth bar. They shaver one row after another off, as if they are nibbling an ear of corn.
From the upstream to downstream tip measures more than half a mile.
At the eastern end, it almost look as if a bored dredging is carving his initials in the bar so that they can be seen from outer space.
Looking south across the eastern edge toward the FM1960 bridge again.

Tonight, as we watch Tropical Storm Cristobal dump torrential rains on Mexico, it’s hard to escape thinking of Hurricane Harvey. It dumped torrential rains on Houston and formed this monster mouth bar almost overnight. Remember, like an ice berg, the part you see above water is only a tiny percentage of what you can’t see below water.

Thinking of Cristobal, Remembering Harvey

As I look at the cloudless skies and soft sunset, I can’t help but wonder. Will Cristobal miss us. Or is this just the calm before the storm?

Cristobal has produced life-threatening flash flooding in Mexico and Central America. The National Hurricane Center forecasts it to move northward across the Gulf of Mexico on Friday. Risks include storm surge, rainfall and wind impacts this coming weekend across the US Gulf Coast from Texas to Florida. NHC reiterates that it’s too soon predict the exact location, timing and magnitude of these impacts.

Posted by Bob Rehak on 6/3/2020

1009 Days since Hurricane Harvey

Putting Mouth Bar Removal in Larger Context; Need for Maintenance Dredging

As mechanical dredging whittles down the part of the San Jacinto West Fork mouth bar that sticks up above water, it’s important to think about longer-term maintenance dredging. Remember three things:

  1. How the sand got there in the first place
  2. Why it will be redeposited over time
  3. What the consequences will be of not removing it periodically

How Sand Got There

Most movement of sediment happens during floods. Sand and silt washes downstream from two main sources: natural and man-made.

The natural sources include erosion from river banks and beds.

The man-made sources include the dirt that washes into your storm drain during a rain. They also include new developments and construction sites that disturb the soil without adequate safeguards like silt fencing. Finally, in our area, we also have an abundance of sand mines that pump and/or dump silty wastewater into rivers.

Why It Will Be Redeposited Over Time

So-called mouth bars are giant sand bars formed at the mouths of rivers. They form wherever a river enters an ocean, sea, estuary, lake, or reservoir. Whenever water slows, a river will deposit sediment. And it always slows when a moving body of water encounters a standing body of water. It’s a well understood geophysical process that occurs everywhere around the world. A prime example is the Mississippi delta.

Mouth bars are actually part of river delta formation. As they build up, they force a river to split.

Why Intervention Is Necessary In Populated Areas

As sediment builds up, if left alone, it will eventually choke the headwaters of the lake and form a flat swampy lowland. You can already see this beginning to happen on the East Fork San Jacinto.

Looking north at northern part of East Fork Mouth Bar, which has become vegetated. Note how it causes the river to split. The river is carving itself up into a maze of small channels. Photos taken 5/11/2020.
Here’s the area immediately below the shot above. It is near the entrance of Luce Bayou to the East Fork. This area went from 18 feet deep to 3 feet after Imelda according to boaters. Photo taken 3/5/2020. Note how the newest mouth bar is forming in one of the channels formed by the previous mouth bar which has become anchored by vegetation.
Looking west toward West Lake Houston Parkway Bridge and the West Fork of the San Jacinto. Note how this mouth bar also caused the river to split. Sediment is now being deposited on both sides, and will eventually cause another split without more dredging. Photo taken 5/11/2020.
Looking south toward FM1960 from north of the mouth bar. Notice how shallow this section of the river has become. The loss of conveyance contributes to flooding. Photo taken 5/11/2020.
From Harris County Flood Control District’s page on the on-going Kingwood Area Drainage Assessment.

Part of the reason for the buildup of sediment behind the West Fork mouth bar is that Ben’s Branch and another major drainage ditch have been dumping sediment into the river there. Luckily, HCFCD is removing sediment from these and other ditches. That will help reduce the problem in the river, but not eliminate it.

Need for Maintenance Dredging

Erosion is relentless. We can do many things to minimize it (preserve wetlands, use best management practices in sand mining and construction, etc.). However, as long as rain falls, we can’t eliminate it.

To my knowledge, until the emergency West Fork dredging program began in 2018, the upper San Jacinto had never been dredged since the Lake Houston Dam was built in 1953. That’s 65 years. Over that time, sediment build up turned into a $100+ million dredging program. And that doesn’t even include flood damages which likely total another BILLION dollars according to a City estimate. Imagine all the heartbreak and misery that could have been avoided had the City budgeted $2 million for dredging each year.

Dredgers keep nibbling away at the mouth bar like an ear or corn, removing one row at a time. Photo taken 5/11/2020. Unfortunately, the effort to remove the portion of the bar above water may make people think the problem is solved, but it won’t reconnect the upstream river channel with the lake.

Imagine the:

  • Flood losses we could have avoided
  • Recreational opportunities we could have realized
  • Reservoir capacity we could have preserved
  • Home values we could have multiplied.

For all these reasons, we need to start a serious dialog about maintenance dredging. Even if it’s not every year, we need it after every flood. Think of it as a yearly insurance premium against the next disaster.

The Army Corps estimated this bar immediately downstream from River Grove Park blocked 90% of the West Fork. In the three months before the Corps removed it, River Grove flooded six times. Since then River Grove has not flooded at all.

Posted by Bob Rehak on 5/22/2020

997 Days after Hurricane Harvey

HCFCD Finishes Clean-Out of Its Portion of Rogers Gully; But Mouth Bar Remains

Aerial photos taken on April 21, 2020 show that Harris County Flood Control District (HCFCD) finished its Rogers Gully project in the Walden area of Lake Houston south of FM1960. However, a significant mouth bar remains in the portion of the ditch owned by the City of Houston.

Looking west from shoreline of Lake Houston. Harris County Flood Control excavated accumulated sediment earlier this year in the visible portions of Rogers Gully.
Looking east from same position, shows work still remains in the City-owned portion of Rogers Gully.

Project Did Not Extend to Lake Houston

The channel repair project extended from Trophy Place to approximately 1,400 feet downstream. Matt Zeve, Deputy Executive Director of HCFCD, said “We had worked this location a year ago, and the sediment accumulated in this spot again very quickly, so we had to come back.”

However, he added, “We won’t be getting the mouth bar.” The mouth bar is yet another one of the jurisdictional issues that plague homeowners around Lake Houston. The map below shows the HCFCD right-of-way in yellow. City of Houston (COH) is the red (actually COH owns all of the lake area even though it doesn’t show up on the map).

HCFCD excavated the yellow portion of Rogers Gully.

Zeve also said, “The mouth bar will have to be handled by another dredging contract that will come after the COH executes the $30 million program.” The $30 million program refers to the Huberty Amendment to SB500 passed during the last legislature.

The April photo of the mouth bar above was taken after a large rain when the lake level was up slightly. When the level is down, here is what the problem looks like.

Still shot from Jack and Greg Toole’s video. Used with permission.

The Rogers Gully mouth bar still appears to have the potential to back water up and contribute to neighborhood flooding.

Posted by Bob Rehak on 5/10/2020

985 Days after Hurricane Harvey and 234 after Imelda

Whittling Down the San Jacinto West Fork Mouth Bar

The State of Texas, Harris County and the City of Houston are whittling down the mouth bar of the San Jacinto West Fork – teaspoon by teaspoon. Just kidding; it only feels that way.

At the planned rate, the partners will remove approximately one third to one half of the planned 400,000 cubic yards of sediment by the start of hurricane season. But after waiting two and a half years since Hurricane Harvey, any and all progress is welcome! I’m not complaining.

The Mouth Bar Immediately After Harvey

Harvey deposited massive amounts of sediment in the area where the San Jacinto meets Lake Houston.

The mouth bar two weeks after Hurricane Harvey. With the exception of the treed areas on the extreme right, Harvey deposited virtually all the sand you see here plus more that you can’t see underwater.

The Army Corps of Engineers dredged a 600-acre area south of the mouth bar three feet deeper last summer. However, they barely touched the part of the mouth bar above water.

The mouth bar created a sediment dam behind the Lake Houston Dam that contributed to flooding more than 4100 structures in the Humble, Kingwood, and Atascocita areas.

Why Mouth Bar Formed Where It Did

The mouth bar formed where it did because the river water slows down when it meets the lake. The lower velocity causes sediment to drop out of suspension and accumulate faster.

While the Corps used hydraulic dredging to remove 500,000 cubic yards from the mouth bar in three months, the current phase uses mechanical dredging. Partners hope to remove another 400,000 cubic yards in 12 months. The process resembles whittling in that workers remove small chunks at a time.

Big Machines Dwarfed by Size of Job

Mechanical dredging uses large excavators. They load the sediment on pontoons. Tugs then push the pontoons upriver to a placement area. There, skid loaders remove the sediment and put it in trucks. The trucks cart it inland.

The excavators are currently nibbling away at the southern edge of the bar. I took all photos below on 3/6/2020.

Excavators are nibbling row after row, like from an ear of corn. This shot shows the immensity of the task.
They load one pontoon while another waits. The West Fork now has its own shuttle service. Unfortunately, round trip is still more than two hours.
These double pontoons can carry an estimated 160 cubic yards. Project goal: 400,000 cubic yards. That’s about 2,500 round trips for the pontoons.
Keeping the pontoon balanced requires coordination.
Tugs then push the pontoons upstream.
Dock of the placement area on Berry Madden’s property south of the West Fork, opposite River Grove Park boat dock on north shore.
From there, trucks haul the sediment inland out of the floodway, about a mile from the river. And the cycle repeats itself.

Mechanical vs. Hydraulic Dredging

The whole process resembles a five-mile long conveyor belt. It involves excavators, pontoons, tugs, trucks and more. Both mechanical and hydraulic dredging have advantages and disadvantages. Hydraulic dredging takes more time to mobilize, but re-suspends less sediment, and costs less per cubic yard of sediment removed. Mechanical dredging, on the other hand, can mobilize much faster.

At this point, returning to hydraulic dredging feels like a distant dream. No one is commenting on the possibility. But this picture speaks volumes.

Former Army Corps command post for West Fork Emergency Dredging project

It shows the once-bustling, but now-empty Army Corps command post. Just three months ago, it was filled with dredge pipe, spare parts, construction trailers, pontoons, booster pumps, survey boats, and more. Getting all that equipment back will be difficult.

Posted by Bob Rehak on 3/12/2020

926 Days since Hurricane Harvey

Hidden Costs of Flooding

When we think about flooding, most of us don’t think beyond the repair costs of homes. But there are more costs to communities that can remain hidden for years. Erosion, for instance, is one of the hidden costs of flooding that we rarely talk about.

You’ve heard me talk about the eroded sediment from sand mines that winds up downstream in the mouth bars of the East and West Forks of the San Jacinto.

The City, County, State and Federal Government have already spent more than $100 million to remove eroded sediment that is blocking the West Fork of the San Jacinto and much more remains.

Likewise, many of you have seen the work being done now to remove approximately 80,000 cubic yards of eroded sediment from Ben’s Branch.

Ben’s Branch became virtually blocked with sand after Harvey. Harris County Flood Control is now removing the excess sediment to restore conveyance of the channel.

We’ve all seen how such eroded sediment can back water up and raise flood levels. And we’ve all seen how much that can cost. Not just from the initial flood, but in terms of remediation.

Look At the Cost of Erosion From the Upstream Side, Too

Ditch erosion can affect homeowners in other ways, too. By threatening their property and community property. Lost property is yet another one of the hidden costs of flooding.

We’ve seen how ditch erosion destroyed riding trails in the Commons on Lake Houston.

Ditch erosion in Commons on Lake Houston. Photo from January 2019.

In Deer Ridge Estates, ditch erosion is creeping inexorably toward back yard fences.

Kingwood diversion ditch where it crosses past Deer Ridge Estates just north of Deer Springs Drive. Photo from Jan. 2019.

On a recent flight down the San Jacinto West Fork, I spotted erosion threatening the back yards of homes still under construction in the new Northpark Woods subdivision.

Erosion can threaten pipelines, too.

Pipelines undermined by erosion at Liberty Materials Mine near Conroe.

Let’s Play Hot Potato

Who is responsible for repairing the upstream erosion when it happens? In Harris County, we’re lucky, we have a flood control district that has assumed responsibility for that. But the ditch two photos above is in Montgomery County. So are the pipelines in the photo above.

Who is responsibly for repairing erosion in these cases? The County? The homeowners? The homeowner association? The developer? The sand mine? The pipelines? A flood control or drainage district? Everyone wants to assume it’s someone else’s problem. No one wants to assume responsibility.

But without someone stepping up, these homes will eventually be threatened. And with the exception noted above, few people or groups are stepping up.

Paul Crowson, a Montgomery County flood activist has posted about this subject on Facebook. Says Crowson, “The county, the flood control district, the neighborhood HOA, the POA, the City, the State, the developers, the engineers … all are passing the blame and responsibility around to each other.”

The problem exists everywhere. Crowson points to the case of Fort Bend County homeowners who are petitioning the Court there to assign responsibility for maintenance of drainage easements.

“These poor people (in the court case) have lost most of their yard, and are in danger of losing their home to the ravages of the drainage easement nightmares,” says Crowson. “Those nightmares are growing every day and will eventually swallow them and their home. Why does it matter to you? I’m thinking right now of Roman Forest, Tavola, New Caney, and Montgomery County.”

It’s Easier to Keep Up Than Catch Up

I would argue that it’s cheaper to prevent a disaster in the making than to remediate a disaster after the fact. Remember those homely homilies your parents and grandparents tried to instill in you? An ounce of prevention is worth a pound of cure. A stitch in time save nine.

Congressman Dan Crenshaw says the Navy Seals have a similar saying for those who fall behind on those long training runs they take. “It’s easier to keep up than catch up.” They’re all true! And the same holds true for deferred maintenance.

When Deferred Maintenance Turns into a Disaster Area

Montgomery County does not have a flood control district. Nor does it seem especially eager to address problems, such as those in the photo above.

As we saw with the mouth bar on the West Fork that had been building up under water for decades, maintenance can be deferred for only so long.

Then a monster flood comes along like Harvey. It finds the weak points in systems…and boom. Deferred maintenance turns into a disaster area.

Posted by Bob Rehak on 2/28/2020 with input from Paul Crowson

913 Days after Hurricane Harvey