Army Corps Now 70% Complete with Its Portion of Mouth Bar Dredging

The Army Corps has released a new summary of its progress on dredging the mouth bar. The report indicates that Great Lakes, the contractor is now 70% complete. They have dredged 350,000 out of 500,000 cubic yards.

Great Lakes started dredging the mouth bar on June 25th, 2019, as part of a $17,085,861 extension of the original contract (FEMA mission assignment SWD-30).

Current area of operation is the blue area on the far right. Sediment removed from that area is being pumped 10 miles back upstream to Placement Area #2, a sand mine near Kingwood College, on the far left.

Between the start of mouth bar dredging and August 12, Great Lakes dredged an average of 6,363 cubic yards per day. If they can keep that pace up, they should be done by approximately Labor Day – three months ahead of schedule. That’s HALF the predicted time.

Remainder of Project Still Not Decided

What comes next? That still has not been finalized. City, County and State officials have been meeting in the background to determine that. The Army Corps still has not accepted or rejected Berry Madden’s property as a third placement area. And the $30 million appropriated by the State for mouth bar dredging won’t even become available until September 1st.

Meanwhile, Callan Marine, the subcontractor from the original West Fork Emergency Dredging job has pulled its equipment back to the dock opposite Forest Cove. However, Callan has not yet started disassembling its equipment and removing it from the river. According to Houston City Councilman Dave Martin, Callan has agreed to stay temporarily while officials attempt to work out details for the next phase of dredging.

RD Kissling and Tim Garfield, two local geologists who first brought the mouth bar issue to the public’s attention, estimate that 500,000 cubic yards is about one-fourth of the total sediment that must be removed to fully restore conveyance of the West Fork.

How Shallow is It?

The Corps has not yet released (or even developed) plans for mouth bar dredging. We do know the volume they intend to remove, and the general area they intend to remove it from. However, they have refused to divulge how much of a dent their efforts will make in solving the problem.

This photo of a Kings River resident wading across the river shows how shallow it is near the orange channel marker. This resident says boats “beach” behind his property almost every day. Note: Deeper pockets may exist, especially near dredging equipment. The risk of drowning is real. Do not let children attempt this. Photo taken Sunday, August 10, 2019.
The resident made it almost to the channel marker without getting his shorts wet. Shot taken with 6X telephoto lens.
The lake/river within this area averages two to three feet deep. 500,000 cubic yards would lower the average level by another three feet as this calculation shows.

Problem With Stopping after 500,000 CY

The problem with stopping after the Corps finishes its 500,000 cubic yards is that the river behind this area is much deeper. Where the Corps stopped dredging just past Kings Harbor, the river is now 25-30 feet deep. And places are even deeper according to fishermen. That means water coming downriver will be forced to flow uphill in this area. That will force it to slow down and more sediment will rapidly drop out of suspension. Some experts have suggested dredging a deep channel through this area to help restore full conveyance of the river. However, the Army Corps intends to stop after 500,000 cubic yards.

How Army Corps Sees its Role

The Army Corps has prepared a series of FAQs that represent its position on the remainder of mouth bar dredging. Among them:

Q: What is USACE Galveston District’s plan for the rest of the mouth bar?

A. There is no additional work planned for the mouth bar. The current plan for the modification addressing material near the mouth bar can be found on the placemat. USACE Galveston District has no authority to conduct any additional work in the West Fork of the San Jacinto River or Lake Houston. The San Jacinto River is not an authorized federal waterway, the Corps of Engineers dredging operations are currently limited to dredging Harvey-related material. The ongoing work under the contract modification will remove the remainder of material attributable directly to Hurricane Harvey. The sedimentation from recurring annual flows are not within USACE Galveston District’s mission assignment from FEMA. Water flows on the West Fork of San Jacinto River were restored to pre-Harvey levels in December 2018.”

Q: Who can the public contact for additional concerns with the maintenance of the San Jacinto River?

A. For concerns with the maintenance of the San Jacinto River, please contact Harris County Flood Control District, the San Jacinto River Authority and the City of Houston.”

Punt!

Meanwhile the City is still arguing with the Corps about how they arrived at 500,000 cubic yards. More on that later. I have obtained the Corps’ estimate through a FOIA request to the City of Houston. It raises many questions that I am still trying to sort through. More on that later.

Posted by Bob Rehak on August 14, 2019

715 Days since Hurricane Harvey

How This Hurricane Season Compares to Others So Far

With two weeks left in August and no active tropical systems in the Atlantic, Caribbean or Gulf, I started wondering how this hurricane season stacked up against the average. Through the end of July, we had two named storms in the Atlantic. We also had six in the eastern Pacific, none of which threatened land. That makes a total of eight. How does that compare to a normal year? Below is a chart from NOAA. It shows the averages for tropical storms and hurricanes by month.

167 Years of Hurricane History

The first thing I noticed when looking at this table is the clear jump between July and August. Through the end of July, the averages for both tropical storms and hurricanes are below 1. That means the chances of NOT seeing one are greater than seeing one. However, August is where things heat up (pardon the pun). Your chances of seeing one are far greater than NOT seeing one.

Source: NOAA

Distribution of Atlantic Storms by Month

Through the end of July, we exceeded the averages for The Atlantic and Pacific combined. But if you look at just the Atlantic, we are about on average, as the chart below shows.

Source: NOAA
Cumulative Number of Storms Per 100 Years in The Atlantic Basin. Source: NOAA

The official hurricane season for the Atlantic Basin (the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico) is from 1 June to 30 November. As seen in the graph above, the peak of the season is from mid-August (now) to late October.

Current Outlook Clear

However, THIS August has been quiet so far. Season-to-date, we are still slightly above average, but the month of August is unusually quiet. We’re halfway through the month without any named storms in the Atlantic and NOAA expects no activity for the next five days.

Source: NOAA. As of 8/14/19 at 8am EDT.

Regardless, if you are the type to play the odds, so far this year Texans have to consider themselves lucky.

Lake Levels As of Mid-August

With that in mind, let’s look at what the San Jacinto River Authority (SJRA) and Coastal Water Authority are doing with Lake Conroe and Lake Houston to reduce the chance of flooding in the event of a major storm.

Both lakes are down about a foot. This creates an extra buffer against flooding by creating extra capacity within the lake.

The SJRA began lowering Lake Conroe on August 1. Normal level is 201 feet above sea level. As of this morning, Lake Conroe was at 200.03 feet and the SJRA continued to release water at a minuscule rate of 150 cubic feet per second. Evaporation is doing most of the work. The SJRA says the lake can lose up to an inch per day through evaporation in hot, dry weather, which we have had plenty of lately. You can always check the current lake level at SJRA.net.

The Coastal Water Authority is maintaining Lake Houston at 41.57 feet above sea level. Normal level is 42.38 feet. A recent lowering for dam maintenance combined with lack of recent rain and evaporation have all contributed to the current level.

The SJRA will continue releasing water at a rate that brings Lake Conroe down to 199 feet by September 1. The SJRA will maintain that level through the end of September, then allow the lake to gradually refill with rainwater until it reaches the normal level of 201 feet.

Pre-emptive seasonal lowering helped avoid flooding last spring. Keep your fingers crossed!

Posted by Bob Rehak on 8/14/2019

715 Days since Hurricane Harvey

Respect the Rivers

Jill Boullion, Executive Director of the Bayou Land Conservancy, sent me a link to a fascinating article called Fossil Rivers. It’s about the evolution of the Mississippi River. Even if you’re not a student of geology, the maps are worth looking at as pieces of abstract art. As the author of the article, Geoff Manaugh says, “Colors coil round other colors; abstract shapes knot, circle, and extend like Christmas gift ribbons. This is geology as a subset of Abstract Expressionism: rocky loops of the Earth’s surface in the hands of Jackson Pollock.”

Army Corps map showing the geomorphology of the Lower Mississippi over time.

Says Manaugh, “Indeed, what the Army Corps of Engineers discovered while producing these maps is that the Mississippi River has changed channel completely – and it has done this hundreds, even thousands, of times. In fact, the river’s endless self-alteration still occurs, even as you read these words: the Mississippi, like all rivers, is migratory, destined to wander across the landscape for as long as it continues to flow. It drifts back and forth – sometimes a few feet, sometimes a mile – walled in by its own silt and debris; until there is change: a natural levee fails, or a storm surge bursts into another watercourse nearby, and then the river finds itself on a quick new route to the sea.” 

Powerful reminders to respect the rivers! Give them room. Those who build too close will lose in the long run. People can moan about property rights all they want. But in the end, Mother Nature always wins.

Posted by Bob Rehak on 8/13/2019

714 Days since Hurricane Harvey