News - Reduce Flooding

Northpark Channel approximately 3,000 feet back from where it normally enters West Fork beyond bottom of frame.

Flood Photos Raise Disturbing Sand-Mining Issues Again

Photos taken during last week’s flood raise disturbing questions all over again about sand mining so close to the San Jacinto.

Are:

Dikes strong enough? No.
Dikes high enough? No.
Setbacks from the river far enough? No.

Can:

Current flow through the mines? Yes.
The river stir up sediment? Yes.
The sediment escape the mines? Yes.

Will:

Miners convince legislators that the answers above are false? Yes.
More sediment in the river reduce conveyance downstream? Yes.
Anything change? No.

The sand mining photos below show dramatically that the river breached dikes, flowed through pits, stirred up sediment and carried it downriver. I have hundreds more, but these make the point.

Photos Taken May 3/4, 2024

In the picture below, the drainage channel bisects two abandoned sand mines that sit just downstream of the massive Hallett mine (out of frame to the left). Note current flowing from left to right and mixing with the clearer water in the drainage channel.

This photo and those below say at a glance how much sediment is being washed through and out of the sand mines.

Reverse angle in same area shows how large the mine complex is. At this point it is more than a mile wide (E to W) and 2.5 miles from N to S. River flows from upper right to upper left. Can you even tell where the river is?

*Leak in dike of Hallett Mine into San Jacinto West Fork. Note water flowing over another dike into another pond in the background.* *River flows between the foreground and background.*

*Higher, wider shot from same area as above. Notice how river has penetrated Hallett pit on right in multiple places.*

*River flowed through that pit at the Hallett Mine on the San Jacinto West Fork*.

*Breach at far end of Hallett pit above has been open since January. Note river current cutting through pit and back into river at lower left. River flows from right to left.*

Sediment Contribution to West Fork

The West Fork will remain above flood stage through tonight. It will be interesting to see how much new sediment works its way downstream. We will need a new river survey to document that.

The SJRA may also have to revise the conclusions of its recent sedimentation survey.

Luckily, the City of Houston has just started another dredging program to remove another 800,000 cubic yards of sediment above FM1960 where the East and West Forks come together.

*Callan Marine getting ready to dredge northern part of Lake Houston*

Good timing on that one.

Last question. Will the City be able to keep up with all the sediment coming downstream? No, in my humble opinion. At least not if we permit the sand mines to continue operating the way they do.

Gage readings at SH99 and US59 on the West Fork suggest that this was a 25 to 50 year flood. But the dikes should have been built to withstand a 100-year flood.

And while the mines above are built right next to the river, most other states require setbacks ranging from 100 to 1000 feet.

The Never-Ending Story

During Harvey, these same sand mines were implicated in contributing to the formation of sandbars downstream which reduced the conveyance of the West Fork. According to the Army Corps, the West Fork was 90 percent blocked in the area below. And that contributed to the flooding of thousands of homes and businesses.

*South of the Kingwood Country Club’s Island Course, Hurricane Harvey deposited several feet of sand. It took the Army Corps months to dredge this area.*

We seem to have developed a system whereby taxpayers subsidize miners. That only seems to encourage them to adopt more dangerous behaviors.

As one long-time resident who lives near the mines told me, “If Hallett thinks they can get away with something, they will try.”

In the miners’ defense, they claim they support the area’s growth. But that also entails clear-cutting thousands of acres. And you guessed it! That creates more erosion that clogs our rivers with even more sediment. More on that tomorrow.

The question is not whether we can live without sand mining. It’s whether we can have more responsible sand mining and development practices.

Posted by Bob Rehak on 5/7/2024

2443 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.

Flood Damage Revealed as Waters Recede, Please Report It

5/6/2024 Part II – Flood damage to an unknown number of homes and businesses is being revealed around Lake Houston as waters recede. Most of the serious flood damage seems confined to low-lying homes around rivers and streams.

As I drove around the headwaters of Lake Houston this afternoon from Kingwood to Huffman to Porter and back, I saw plenty of those.

In this post, I will first show some of those photos.

Then I will make a special request that could help this area receive federal assistance. Filling out a simple survey for the Texas Division of Emergency Management (TDEM) could help neighbors without flood insurance. But first the photos.

Photos From Harris and Montgomery County Taken on 5/6/24

Dunnam Road, Kingwood

Submitted by Sharai Poteet.

Northwood Country Estates in Huffman

Submitted by Max Kidd.

*Northwood Country Estates, Huffman*. *By Max Kidd.*

River Club Estates, Porter

Lakeside, Kingwood

Sadly, many of the homes I photographed today had been flooded before. And they hadn’t unflooded yet. As I write this on Monday May 6 at 9 PM, the gage at US59 still records a flood level of 53 feet – 10.5 feet above the normal river level for this area. So, some homes remain underwater and inaccessible.

The worst of the flooding may be over. But the West Fork is still at the major flood stage! It should go down to the moderate flood stage on Tuesday and the minor flood stage on Wednesday.

Request from Officials to Report Flood Damage

Elected officials called me today to request assistance. They’re not certain whether there will be enough damage from this storm to qualify for a disaster declaration and Federal assistance.

So please follow these instructions to report damage if you have it.

Go online to the Texas Division of Emergency Management.
You should be at a page that says, “Individual State of Texas Assessment Tool (iSTAT) Damage Surveys.”
Click on the “Spring Storms” link.

Why It’s Important

The objective of this survey is to help state and local emergency management officials across Texas identify and gain an understanding of flood damage that has occurred. If there are enough qualifying damaged structures in your county, residents of your county could qualify for Federal assistance.

Only one survey per family. And the surveys can only be filled out online. They are very simple and you should be able to do them from a phone if your laptop or desktop was destroyed. It should take no longer than five minutes if you have damage photos ready.

They give this guidance for photos.

\✅	Take multiple photos from different angles including close-up photos of specific points of damage and photos of the entire structure.
✅	Make sure your photos aren’t blurry or obscured.
✅	Double-check your address as well as the location pin on the in-survey map.
❌	Don’t submit reports of non-residential structures or outbuildings (barns, carports, fences, or cars).
❌	Don’t submit multiple iSTAT entries for the same residence.
❌	Don’t put yourself in a dangerous situation in order to take photos or submit an iSTAT entry.

Reporting damages to TDEM is a voluntary activity. It is not a substitute for reporting damage to your insurance agency, and does not guarantee disaster relief assistance.

Why You Should Take Survey Even if You Have Flood Insurance

Since Harvey, people who are uninsured and not required to have insurance may qualify for FEMA benefits. However, 500 people per county must qualify before anyone in the county gets anything.

Individuals may qualify for SBA loans, housing assistance, etc. It just depends on whether the thresholds are met. This survey is the first step in assessing needs.

As I drove around the headwaters of Lake Houston today, I saw several pockets of damage, usually close to the rivers. And I am sure more exist.

So please share this post with everyone you know to make sure all residents with qualifying damages report them to TDEM. Even if you have insurance, your neighbor may not. Beating that 500 minimum per county could help them and help your neighborhood recover faster.

Posted by Bob Rehak on 5/6/2024

2442 Days since Hurricane Harvey

Where The Water Came From: May Flood Dissected

May 6, 2024, Monday 2 AM – Flooding in the Houston area during the first week of May 2024 caused quite a stir. It made national headlines most days last week. Twenty percent of the region’s annual rainfall fell in two or three days in several places upstream from Lake Houston.

Water rose quickly along the West and East Forks of the San Jacinto. Several homes flooded in Kingwood. But thousands more were on the verge of flooding when water finally started to recede yesterday.

Thankfully, rainfall Sunday in most places was on the low side of predictions. And at this hour, all gages continue to head downward with the exception of one or two far upstream to the northwest.

As last week wore on, people rode an emotional roller coaster from uncertainty to anxiety, fear, relief and, for some, anger. If lives weren’t destroyed, they were certainly upended. Many are searching for someone to blame for sleepless nights.

So let’s try to dissect what happened during this event. Then, let’s try to draw some conclusions and identify questions that remain to be answered.

How Much Rain Fell Where

Fortunately, the Harris County Flood Warning System, USGS National Water Dashboard, and SJRA have put a lot of tools at our disposal.

The first thing to check is how much rain fell where. HarrisCountyFWS.org makes that easy.

Go to the home page.
Under Site Selection/Sites by Agency, select All.
Under Rainfall Data, select Last 7 days.
Click the Watersheds option in the View tab (top left)

You should get a map that looks like this.

*From Harris County Flood Warning System, 5/5/24 at 10PM*

Note the extreme figures:

18.16″ and 17.8 inches that fell above Lake Conroe’s Dam
16.52 inches south of the Lake Conroe Dam
17″ in the Peach and Caney Creek Watersheds,
16″ in the East Fork Watershed
15.4″ in the Luce Bayou Watershed.

How Runoff Converged

To get a better feeling for how these watersheds connect, consult the map below without all the visual interruptions. I’ve circled the area that drains into Lake Houston in red.

From this you can see that the upper San Jacinto watershed draining into Lake Houston is immense.

The Texas Water Development Board provides some statistics. The size of the:

Entire river basin is 3976 square miles.
Area circled in red is 2828 square miles.
Area draining into Lake Conroe is 445 square miles.

So…

71% of the entire river basin drains through Lake Houston. Only 15.7% of the area draining into Lake Houston comes from above the Lake Conroe Dam.
Calculations based on TWDB data.

There are no other dams in the watershed. So, 84.3% of the area is beyond the control of the SJRA including everything on the East Fork.

But still, did SJRA save the water up too long and then release it in a giant pulse that swamped Humble, Kingwood and Atascocita? That’s a little harder to tell. We’ll come back to that later.

But USGS gives you a fast, simple way to learn where and when water peaked.

Peak Flows Compared from Different Tributaries

Go to the USGS National Water Dashboard. It’s a central repository for all gages that measure discharge rates.

Note: the term “discharge” applies not only to water released from a dam. Hydrologists also use the term to describe water flowing under a bridge. Discharge is measured in Cubic Feet Per Second (CFS).

Let’s look at how major streams in the watershed compared.

East Fork and Tributaries Above Lake Houston

*East Fork at FM1485 in New Caney peaked at 68,000 CFS on Friday, May 3, 2024 *6:45 PM* .*

*Luce Bayou peaked on Friday May 3 at 4PM at 12,100 CFS.*

*Caney Creek peaked at 18,900 CFS Friday May 3 at 12:15AM.*

*Peach Creek in Splendora peaked at 10,300 CFS on May 3 at 9:30 AM.*

Peak discharges are not directly additive because the peaks occurred at different times.

West Fork

I won’t post graphs for every tributary on the West Fork. But let’s look at two key points: below the Lake Conroe Dam and at US59.

That’s the only portion of the river system that SJRA controls. All other West Fork watersheds, such as Spring, Cypress, Little Cypress, Willow and Lake Creeks, enter the river below there. They all peaked at different times.

But by the time water got to US59, the combined peak was slightly higher – 82,700 CFS.

*West Fork at 59. Peak discharge of 82,700 CFS occurred on May 4 at 10AM.*

Main Stem of San Jacinto Below Lake Houston

And by the time all the water from the East and West Forks went over the Lake Houston dam, the San Jacinto downstream in Sheldon peaked at 157,000 CFS.

*San Jacinto River at Sheldon downstream from Lake Houston peaked at 157,000 CFS on Saturday, May 4 at 11:30 AM.*

Conclusions

Several things should be clear at this point.

The SJRA release from Lake Conroe wasn’t responsible for all the water flowing into Lake Houston.
SJRA doesn’t control any water on the East Fork where the worst home flooding apparently occurred. Official damage reports may take weeks.
The broken gate on the Lake Houston Dam (one of four with a combined release rate of 10,000 CFS) made no difference at the peak of the flood. By then, the 3160-foot-wide spillway was discharging a 5+ foot wall of water every second – more than 150,000 CFS, compared to 2,500.

Unanswered Questions

Having said that, I believe we definitely need to do an “after-action report” on this flood. Engineers need to answer questions, such as:

How much sooner should we have started pre-releasing water from Lake Houston to have made a difference?
Did SJRA wait too long to start releasing? Would an earlier release at a lower rate have made a difference?
Did the new SJRA strategy of throttling back releases every 2 hours help downstream? Or harm anyone upstream?
Why is it taking so long (almost 7 years) to figure out how to add more floodgates on Lake Houston?
Why don’t we have more upstream detention yet, one of the basic mitigation strategies identified after Harvey?
What was the role of Colony Ridge in the East Fork flooding? It covers an area 50% bigger than Manhattan and has virtually no detention basins holding water back from the East Fork. How did they pull that off?
When this flood recedes, will we see that sediment has once again reduced conveyance?
Why is the Lake Houston Area, which drains an area bigger than Harris County (and which has the most severe flooding in the county) getting so little help from Harris County? We’ve received only $39 million out of more than $1.9 billion spent since Harvey on flood mitigation. That’s 2%.

We need to start these conversations now.