Yesterday, I posted about the discovery of something called the Odom Lake Swamp on a 70-year-old map. Many of the homes that flooded in Elm Grove on May 7 were built in or near it. But learning that required scaling and aligning maps in Photoshop. It’s a time consuming process and not everyone has Photoshop. If you’re considering buying a piece of property, luckily, there’s an easier way to check on its past: the history function in Google Earth Pro.
History Function In Google Earth Pro
Google Earth Pro contains dozens of aerial and satellite images that are already scaled and aligned. The program is a free download and makes scrolling back through time simple. When you first open the program, you’ll see a map of the world. Click on the area that interests you to zoom closer in steps.
Then:
From the menu at the top of the screen, select “View/Historical Imagery”
Click on the Clock icon in the menu bar.
Arrows and a timeline will appear at the top left of the screen.
Scroll back and forth through time by clicking on the arrows.
To show streets that exist today (but that didn’t exist when the image was taken), select View/Sidebar. Then check Labels/Borders and Roads.
Here’s what you see when you scroll back to 1978 (minus the red circle which I added to highlight the area of interest).
Odom Lake Swamp in 1978.
Looking at this, you wouldn’t have known that the large flat, featureless area was called Odom Lake Swamp. But you could tell that something unusual was going on there. And that might tell you to dig further into the area’s history.
“Reading” Satellite and Aerial Images
Google Earth Pro doesn’t show contour intervals as a topographic map would. Nevertheless, it can still tell you a lot. Flat featureless areas like this in the middle of dense forests can indicate ponding, at least on a seasonal basis. Translation: Low area.
Note several other discontinuities in the image above:
A small pond in the lower left (north of Sherwood Trails)
A depression near the upper left that interrupts the straight white line
A triangular area in the upper right where no trees are growing.
In the image below, I zoomed in closer on the Odom Lake Swamp. The image shows what at the time was a dry lake bed. Taylor Gulley had just reached the area and had most likely drained what was a seasonal pond or swampy area. Taylor Gulley itself (bottom right) had not yet been excavated to the county line (thin green diagonal line in upper left).
Close up of Odom Lake Swamp. Taylor Gulley at the bottom was still under development at the time of this image in 1978. Streets had not yet been built in this area. The white lines show where streets are today.
Nature Never Forgets
As one expert told me: “Where old channels, swamps, meanders, etc. were filled in, during major floods, water always seeks the lowest point. Even if you fill in an area, it usually is still the lowest point of a larger area (or watershed) and during large rain storms, the water finds its way there.”
It only takes a one degree slope to make water move across concrete (two degrees through grass or foliage). That’s barely visible. It underscores the need to consult maps and tools like Google Earth when buying property.
Awareness of potential problems is your best way to prepare for or avoid them.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/Odum1978.jpg?fit=1500%2C1062&ssl=110621500adminadmin2019-06-20 14:20:082019-06-20 14:21:10Google Earth Pro: Another, Easy Way to Check on a Property’s Hydrologic History
A 1949 map of the area now called Kingwood reveals that the homes in Elm Grove that flooded on May 7 were built in something once called the Odom Lake Swamp. It turns out, “Nature never forgets.”
Area of interest for this discussion is circled in red.
I previously posted about this map in the context of how the West Fork has shifted over time. At the end of the post, I asked readers to write me if they found anything else interesting. One did. And it was a very interesting indeed.
He pointed to the area circled in red above. When I superimposed that over the present-day image below, my jaw dropped.
Same general area that was superimposed over old map.
It’s True. Nature Never Forgets
The area labelled Odom Lake Swamp matches very closely the outline of the May 7 flood in Elm Grove that damaged almost 200 homes.
I used the county line and the confluence of the East and West Forks to align the two images, then cropped this out of the center.
The reader who reported this came up with a slightly different map that shifts the label “Odom Lake Swamp” to the west side of Village Springs. I am not sure what alignment points he used, but his work and mine closely match.
At a Houston Geological Society seminar on flooding that I attended last year, I remember several speakers talking about this phenomenon, including former Harris County Judge Ed Emmett. During heavy rainfalls, water gravitates toward its original channels.
One expert, who talked to me on condition of anonymity because of the lawsuits swirling around this issue, explained it this way. “Where old channels, swamps, meanders, etc. were filled in, during major floods, water always seeks the lowest point. Even if you fill in an area, it usually is still the lowest point of a larger area (or watershed) and during large rain storms, the water finds its way there.”
Current Flood Map Echoes 1949 Map
He attributed the Elm Grove flooding to a combination of clear cutting without mitigation upstream, heavy rainfall, and lower elevation. In fact, FEMA’s National Flood Hazard Layer Viewer shows that this part of Elm Grove is in the 100-year (aqua) and 500-year flood plains.
I’m not a lawyer and I don’t give legal advice, but it seems to me that this finding does little to change the legal lay of the land (no pun intended).
The residents south and east of Woodridge Village, despite being lower than surrounding areas, had never flooded before – even in Harvey.
Had those ponds been in place, they should have held 13 inches of rain (a 100-year) rainfall. We didn’t get that much. The gage at US59 recorded 6.24 inches on May 7 over six hours. The heaviest rain fell during the noon hour when we got 3.64 inches.
From HarrisCountyFWS.org for May 7. The other official nearby gage at West Lake Houston Parkway received less rain that day.
Harris County meteorologist Jeff Lindner characterized the May 7th event as somewhere between a two and 50-year rain. Experiment with the different possibilities on the chart below.
NOAA Atlas 14 precipitation frequency chart.
Ten Lessons of May 7th
So aside from the Odom Lake Swamp being a historical curiosity, what can readers learn from this.
Flooding doesn’t always come from the river. Streets can flood homes when the rainfall rate exceeds the capacity of storm drains.
Before you buy a home, check historical maps. Learn whether the developer filled in lakes, ponds, swamps, or wetlands and then built your home on top of them. Remember: Nature never forgets!
If the answer is yes, question how much you want the property. Use the knowledge to negotiate a discount with which you can purchase flood insurance. That’s the best way to discourage unsafe development practices.
If you live downstream of an undeveloped area, be aware that floodplains are a shifting target. Just because you’re NOT in a floodplain today is no guarantee that you won’t be tomorrow. Upstream development can cause downstream flooding. So watch carefully.
Pay no attention to anyone who says, “Oh, that area will never be developed.” The more worthless the land, the bigger the profit potential.
If you live in this area, get flood insurance.
If you buy a low-lying home, be prepared to have your life disrupted.
Buyer beware.
Pressure your elected representatives to turn areas such as Woodridge Village into park land. When it was wetlands, it protected the people downstream from flooding and provided recreation.
Buying the property north of Elm Grove could have cost less than the damage to one home. (See appraisal below). Not buying the property was a costly decision.
Ironically, the Montgomery County appraisal district values the 60+ acres of land north of Elm Grove at about a quarter million dollars.
Posted by Bob Rehak on 6/19/2019
659 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/Elm-Grove-Circled-1949.jpg?fit=1500%2C978&ssl=19781500adminadmin2019-06-19 18:25:082019-06-20 13:38:14Nature Never Forgets: Lessons of May 7th Flooding
Tonight, the Lake Houston area is under yet another flash flood watch. Residents of North Kingwood Forest and Elm Grove are wondering whether a new detention pond in Woodridge Village will be enough to protect them.
Another 1-4 Inches of Rain Possible
We may get another chance to test the engineering on the detention ponds in that new Woodridge Village under development in Montgomery County. Our area received 1-3″ of rain today and more is on the way tonight. The area remains under a flash flood watch until 7a.m. Monday morning.
Heavy rainfall and severe thunderstorms will be possible tonight into early Monday.
Jeff Lindner, Harris County Meteorologist warned at 8:30 p.m. Sunday night that, “Numerous thunderstorms are in progress over portions of Liberty, Harris, and Montgomery Counties. Heavy rainfall is the main threat with these cells with recent HCFCD gages in SE Montgomery County recording 2.60 inches in 1 hour. Additional rainfall amounts tonight of 1-2 inches with isolated totals of up to 4 inches are possible.”
The storms appear to be fast moving so the higher totals are less likely than in early May when approximately 200 homes flooded in Elm Grove and North Kingwood Forest just south and east of the area that Woodridge contractors had clearcut.
Role of Detention Pond in Reducing Flood Potential
Had the Woodridge Village S2 Detention Pond been excavated before May 7, it might have prevented much of the flooding. But despite the land being cleared for approximately six months, the pond had not yet been built. LJA Engineers designed the pond to hold 50 acre-feet of runoff. What does that mean?
How Much is An Acre Foot?
One acre foot would cover an entire acre to a depth of one foot. An acre is about the size of a football field. That means 50 acre feet would cover:
One football field to a depth of 50 feet
50 football fields to a depth of one foot
Or, in the case, of this pond, about 3.5 acres to a depth of about 15 feet.
The pictures below show what it looks like today. Very little of this area was excavated on May 7.
S2 has the shape of a hockey stick. Here’s the “face” of the stick. It took a 14mm super-wide-angle lens to get the width of this pond in the frame.This conveys its width but does not adequately convey its depth.This panoramic image was stitched together in Photoshop from seven still images taken with a normal focal length lens. It more accurately conveys the height of the sides. But there’s still nothing in the frame to communicate scale.Although the sides don’t look tall in the previous photo, this is what they look like when you turn and face them. This shot was taken while standing near the bottom. My eye level is more than six feet high and didn’t come halfway up the slope.This notch in the wall of the pond allows water from the ditch behind the grass to overflow into the pond instead of flooding North Kingwood Forest (behind the tree line. That’s the theory anyway … if the calculations are correct.The red circle shows the location of the notch between the pond and drainage ditch beyond it.
Hopefully, the amount of detention in place tonight is enough to handle the rain we get.
Posted by Bob Rehak on 6/16/2019
656 Days after Hurricane Harvey
Thoughts expressed in this post represent my opinions on matters of public policy 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/2019/06/Woodridge6.17.19_01_01.jpg?fit=1500%2C1000&ssl=110001500adminadmin2019-06-16 22:40:432019-06-16 22:43:09Flash Flood Watch in Effect Until 7 a.m. Monday; Luckily, Woodridge Detention Pond Nearing Completion
Officials close to the project say actual dredging could start as early as next week. Dredgers only need more 24″ pipe to pump the sediment 10 miles back upstream to placement area #2, an old sand pit near Kingwood College. However, the City and Corps are still debating the volume deposited by Harvey. The Corps has not yet divulged where it plans to start dredging, what its objectives are for this phase of the project, or what the contributions of other partners will be.
New Drone Video of Mouth Bar by Jim Zura of Zura Productions
New drone footage of the West Fork mouth bar shows just how much the mouth bar has grown since Harvey. I took the still shot immediately below from a helicopter two weeks after Harvey. To see what it looks like today, scroll down. Kingwood-based Jim Zura of Zura Productions shot two new drone videos this morning. They show what the mouth bar looks like 22 months later. As you watch the videos shot from different elevations, consider the immensity of the bar compared to the dredge at the tail end of each video.
Five hundred thousand cubic yards will not come close to restoring the full conveyance of the West Fork. How does 500,000 cubic yards compare with what NEEDS to be dredged?
Let’s start by looking at the channel that the Corps is dredging upriver and assume that they will extend that between the mouth bar and Atascocita Point. That strategy follows the relict channel. The relict channel is also the path with the least sediment at the moment. So that would make the most efficient use of funds.
Let’s also assume that the channel needs to be dredged an average of five yards (15 feet) deeper than its current depth along that path in order to match the profile below.
Endpoint of current dredge program shows channel 22.5′ deep by 400′ wide..
A “budget” of 500,000 cubic yards would allow you to dredge a channel 133 yards (400 feet) wide 5 yards deeper and 752 yards long. That equals 500,080 cubic yards. But 752 linear yards is only about one-fourth of the 3,000+ yards to the FM1960 bridge. And we haven’t even touched the mouth bar!
West Fork Map shows difference in sedimentation between 2010 and 2017. Note the white and violet areas near the FM1960 bridge. Red/orange/yellow/green areas represent decreases in sediment. Blue, violet and white represent increases.
Clearly, dredging the rest of the way to the bridge will require more money from the State, County and/or City. Thankfully for the Lake Houston Area, all of those entities have already allocated funds.
Details Yet to Work Out
However, the City, Harris County, and State of Texas have even more hurdles to clear beyond the volume debate.
They must find a suitable storage site that can accommodate all the sediment they hope to dredge. The storage site represents the biggest obstacle at the moment and a limiting factor.
The Corps would prefer a below ground site, i.e., an abandoned sand pit. That would reduce the risk of future floods carrying sediment back into the river. Also, it would NOT encroach on the flood plain.
Finally, the closer the site is to the dredging, the faster and cheaper the project. Long pipelines lead to more breakdowns. And each additional booster pump uses 1000 gallons of diesel per day.
Latest on Madden Property
The largest property evaluated so far is a 4000-acre site owned by Berry Madden of Humble. Madden’s property is close – half the distance of the sand mine on Sorters Road. It is also large enough to accommodate all the sediment people want to remove – including sediment from maintenance dredging down the road. Permitting one property instead of several would save lots of time (perhaps years).
But storage on Madden’s property would be above ground. Until someone builds on it, that introduces an element of risk that below-ground storage does not have. Madden has conducted an environmental survey of his property and is now conducting an archeological survey required for a storage permit. The Corps has not yet approved his property.
A source close to negotiations says the Corps is considering approving half of the Madden site for now while it performs additional evaluations of the rest of the site. That might be enough to accommodate immediate needs, reduce the cost of pumping sediment ten miles upstream, and provide storage room for future maintenance dredging.
80,000 CY More Sediment Deposited Since Last Survey
Meanwhile, time and sediment march on. Sources say the Corps recently found another 80,000 cubic yards of sediment deposited in the mouth bar area since the last survey after Harvey.
This supports the theory of two top local geologists, RD Kissling and Tim Garfield, who predicted that the mouth bar would form a dam that accelerated sedimentation. That theory also explains why the mouth bar must be removed, or at least why we must dredge a channel around it ASAP.
Posted by Bob Rehak on 6/18/2019with drone footage courtesy of Jim Zura, Zura Productions
658 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/FirstDroneVideo.jpg?fit=1500%2C839&ssl=18391500adminadmin2019-06-16 12:55:552019-06-18 17:39:41Dredge Finally Reaches Mouth Bar
When Elm Grove and North Kingwood Forest flooded on May 7, the Woodridge Village contractor had cleared most of the 268 acres of land north and west of them. The contractor also had sloped the drainage toward those subdivisions without first installing a critical 50 acre-foot detention pond to intercept runoff. Tonight after months of delays, and the flooding of almost 200 homes, work on that pond is almost complete.
S2 Pond Finally Connected to Drainage Ditch Today
Regular readers may remember plans call for a 15-foot deep detention pond shaped somewhat like a hockey stick (see below). The area circled in red is the channel that will connect the pond to the drainage ditch that runs down the east side of the property. Today, some workers excavated that channel while others deepened the pond.
Circled in red: the channel excavated today that will connect the drainage ditch with the detention pond.
Not Much Excavated on May 9
Back on May 9, about a month ago, very little of the pond was excavated when local videographer, Jim Zura, captured this image from his drone. Only a small ditch connected a pond north of Sherwood Trails to the box culvert seen below. The white outline indicates how much of the pond had yet to be excavated.
Almost nothing had been excavatedshortly after the May 7 flood.White outline shows the approximate intended dimension of the pond.
Despite the heavy rains in early May and early June, the contractor now has most of the pond excavated. See the video that Jeff Miller shot this afternoon.
Since the flood, the pond has been widened and deepened. Rebel Contractors is now approaching the pond’s final dimensions and target depth of 15 feet, according to Miller. However, Miller was even more excited about the excavation of the channel connecting the drainage ditch running down the east side of the property to the detention pond. “I’ll be able to sleep with both eyes closed tonight,” he said.
In the future, when runoff drains from the northern part of the property to the southern, it will overflow from the ditch into the pond, rather than into neighbors’ houses.
Recent Excavation Despite Heavy Rains Last Week
The next two shots show what the connecting channel looks like from the ground.
Previously, water in the ditch had to funnel down into the 3′ black culvert (bottom left). This caused the ditch to overflow into surrounding neighborhoods when the ditch got full.Now, however, this channel connects ditch (foreground) and pond (upper left). It will allow runoff to overflow into pond instead of neighbors’ homes.
Bill King Visits Elm Grove Again, Meets Texas Monthly Writer
But that wasn’t the only good news, today. Houston mayoral candidate Bill King visited Elm Grove for the third time in a month and toured the area with Mark Dent, who is covering the story for Texas Monthly.
Bill King (left) and Mark Dent talk about flood mitigation strategies with Taylor Gulley in the background.
King emphasized several needs to Dent. They included:
Greater clarity and accuracy of flood maps, so that people can realistically assess their flood risk
Safer construction practices that better protect downstream residents
Preservation of natural wetlands, buffers and drainage features like those that previously existed on the Woodridge site, and that had protected Elm Grove since it was built.
King emphasized that preserving such natural areas and the wetlands on them can provide both recreation and protection against flooding. Finally, he advocated using buyouts to build more and bigger detention ponds, and also to create more green space.
It’s good to know that King is taking Kingwood issues seriously. He’s making them a centerpiece of his campaign and using them to shine a spotlight on development practices that need improvement in my opinion.
Posted by Bob Rehak on 6/14/2019with help from Jeff Miller
654 Days since Hurricane Harvey, 5 weeks since the Elm Grove Flood, and 4 Months Until the Election
Thoughts expressed in this post represent my opinions on matters of public interest 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/2019/06/Swale_01.jpg?fit=1500%2C1000&ssl=110001500adminadmin2019-06-14 19:41:442019-06-14 19:50:21Critical Woodridge S2 Detention Pond Approaching Final Dimensions
Charles Jones, a Lake Houston Area resident and business man, has developed a presentation that examines the role of the FM1960 bridge in Harvey Flooding. The small openings in the bridge, he says, constrict the flow of floodwaters, much like sand gets pinched and backed up when moving through an hourglass.
The following three slides sum up the heart of Jones’ theory.
Most of the flooding during Harvey happened above the FM1960 bridge on the East and West Forks.The bridge is mostly a causeway. It has two small openings that total 1700 feet.The two openings restrict the flow compared to other bridges and create a backwater effect.
Discussion of FM1960 Theory
Jones’ presentation is a deliberately “high level”, simplified discussion targeted at a general audience. Parts of it seemed a bit OVERsimplified at times.
For instance, at one point he describes the FM1960 bridge as the cause of sediment build up in the mouth bar area on the West Fork. But if that’s the only cause, why isn’t there a similar build up on the East Fork?
Another example: he describes the West Lake Houston Parkway Bridge as 3700 feet in length. That’s true. But so much sand is stacked up on the downstream side of the bridge that it effectively narrows the opening. See sand in the treetops below.
Looking north toward Kingwood’s Kings Harbor. The West Lake Houston Parkway bridge is on the left. Photo taken two weeks after Harvey. In the foreground, sand now reaches the tree tops and is virtually as high as the bridge itself. Water used to flow under the bridge and through the area in the foreground during floods. Now it is forced north.
However, put those observations aside for the moment and ask two simple questions:
Are the principles behind Jones’ theory generally true?
Are there any direct observations available that support the theory?
The answers are yes and yes.
“There’s Always a Bottleneck Somewhere in Every System”
I had a client for 35 years that made plastics. The company was one of the largest and most respected in the business. They built plants around the world. A process engineer in that company, whom I highly respected, once told me, “There’s always a bottleneck somewhere in every system.” The FM1960 bridge is ONE of those bottlenecks.
A Google Earth satellite image taken DURING Harvey shows water swirling above the bridge looking for a way to get downstream. In the photo below, see how the bridge disrupts the different colors in the flow.
Note the different shades of brown near the FM1960 Bridge and how the flow within those colors is disrupted by the bridge, especially by the smaller eastern opening.Satellite image from 8/30/17 DURING Harvey.
So pardon the pun, but I think Jones’ theory holds some water. It certainly merits further investigation. I would certainly like to know the answers to the following questions:
Did someone actually measure the difference between the high water marks on each side of the bridge during Harvey?
If so what was it? Can the backwater effect of the causeway be quantified?
Is there photographic evidence of any difference?
If the backwater effect is significant, how much would it cost to modify the bridge? Would the benefits justify the cost?
Thank you, Mr. Jones, for bringing this matter to the public’s attention. You’ve made a valuable contribution to our understanding of Harvey.
And On a Side Note…
What’s that nasty brown stuff flowing out of Luce Bayou on the upper right in the photo above? At first I thought I might be the shadow of a cloud on that particular day, but it shows up consistently in other photos. See below, for instance. It starts about the time construction on the Luce Bayou project started. That’s the project designed to bring water to Lake Houston from the Trinity River. Mmmmmm!
Satellite image from 12/30/2014 shows purple/brown effluent coming from Luce Bayou.Note the three distinct sediment colors in this photo: light brown in the West Fork on the left, medium brown from the East Fork at the top, and dark brown from Luce Bayou on the right.Most recent Google Earth image from 2/23/19 shows that water coming from Luce Bayou is more normal in coloration now. Construction on the Interbasin Water Transfer Project is required to be complete this month. Let’s hope that’s the last we see of that purple stuff.
Posted by Bob Rehak on 6/14/2019
654 Days After Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/Portholes.jpg?fit=1978%2C1396&ssl=113961978adminadmin2019-06-14 08:22:022019-06-14 14:32:28New Presentation Looks at Role of FM1960 Bridge in Harvey Flooding
Harris County Flood Control District (HCFCD) has enhanced its Flood Warning System at www.harriscountyfws.org.
Flood Warning System Enhancements
The system can now provide:
Residents of Harris AND surrounding counties…
The ability to receive CUSTOMIZED water level AND rainfall alerts…
From ANY gage or gages IN THE ENTIRE REGION…
Via TEXT message, EMAIL, or BOTH.
When signing up, consider the gages nearest you plus those upstream. Upstream gages can give you more warning time.
How to Sign Up for Warnings
Sign up for the new flood warning system at www.fwsalerts.org. Create your free account, then customize your preferences. You can request notifications from more than 250 gage locations across the region. Gages are located in or operated by:
Harris County
Brazoria County
Fort Bend County
Montgomery County
Galveston County
Waller County
City of Mont Belvieu
City of Sugar Land
The Woodlands
San Jacinto River Authority
Residents will need to create an account and can then choose which gages they want to receive information from, i.e., those nearest them and those upstream from them. You can create custom alerts for various water levels, channel depths, rainfall intensities, and so forth. You can also default to four standard alerts.
1 inch of rainfall in 15-minutes
4 inches of rainfall in 1 hour
Channel flooding is possible (3 ft below bankfull)
Channel flooding is likely (bankfull)
When defined rainfall or water level values are reached indicating a potential for flooding, the new flood warning system will begin sending alerts that match your preferences.
Response to Harvey
“One of the biggest takeaways from Hurricane Harvey was the need for automated notifications to be delivered in a timely manner. This enhancement will help do that,” stated Jeff Lindner, Director of Hydrologic Operations and Meteorologist for the Flood Control District.
“Residents can use the new alerts feature to make timely, informed decisions on how to protect themselves, their families, and property,” said Lindner.
More Information
HCFCD has optimized the flood warning system for both desktops and mobile phones.
HCFCD encourages residents across the region to establish an account and sign up for alert notifications at www.fwsalerts.org.
Posted by Bob Rehak on 6/13/2019
653 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/FWS-Signup.jpg?fit=1500%2C1009&ssl=110091500adminadmin2019-06-13 17:20:242019-06-13 17:20:38Flood Control District Enhances Flood Warning System with Customizable Alerts
Geologic change happens so slowly, most people won’t live or stay long enough in one place to perceive it. Then something happens to make you crank up the Wayback Machine and look more closely. Yesterday was one of those days for me. The Army Corps announced that it was going to begin dredging part of the West Fork mouth bar area.
That raised the question, “Which part?” That wasn’t announced. So I asked Tim Garfield, retired chief geologist for one of the world’s largest oil companies, what he would do. He felt it was important to re-establish the river’s natural channel. So I asked him where it was. (Spoiler alert: It’s between the mouth bar and Atascocita Point.) But in the process of figuring this out, I learned many more things about the mouth bar and a river I take for granted. I’ll save those for the end.
70 Years of Change on the River
Garfield led me to the Perry-Castañeda Map Collection of Texas Topographic Maps at the UT Library Online. He found this map from 1949 of Moonshine Hill. It’s exactly 70 years old! The 1949 date means we can see where the river was before the dam and lake were built in 1955.
The San Jacinto in 1949 before Lake Houston was impounded in 1955.For a higher resolution version of this map, click here. This map shows what geologists call “the relict channel.”
Kingwood, Atascocita and Huffman Before Settlement
This map shows areas that would eventually become Atascocita, Kingwood, and Huffman. It includes the area where the mouth bar has formed between Kings Point and Atascocita Point.
You can tell a lot by looking at this map. You can tell even more when you superimpose it over a satellite view of the area today in Photoshop. Suddenly, you see how the landscape has changed. In fact, it changed so much that I had problems aligning the two images.
Map Superimposed Over Satellite Image At Varying Opacities
However, the county line and 1960 are still in the same location. So I used those as reference points. Then I varied the opacity in the top layer (the old map) so that you could see more and more of the current landscape. At different percentages, you can see how various features have changed over time.
Here’s what the sequence looks like starting with 1949 and today. I started by cropping tighter on the area of interest, the West Fork where the Corps is dredging. I include several different opacity ratios because some changes become more apparent at one ratio than another.
100% opacity for 1949 map.0% 1949 and 100% today.60% 1949 and 40% today.50% 1949 and 50% today.33% 1949 and 67% today.25% 1949 and 75% today.
Most Visible Changes
Starting from the left:
In the 33/67 image, notice how the river once meandered near US59 and how much further south it was.
In the 50/50 image, notice how much of the Romerica land was swamp in 1949…and still is.
In the 75/25 image, notice how much the river migrated north just north of Kings River estates.
In the 25/75 image, notice how much area the lake claimed.
In the 33/67 image, notice how far north the river has shifted under the West Lake Houston Parkway bridge.
In the 33/67 image, notice how Atascocita Point has grown past the relict channel.
In the 60/40 image, notice how the mouth bar grew at the confluence of a relict stream bed within the lake and the relict channel of the West Fork. You can also see this pretty clearly in the 25/75 image.
In the 25/75 image, notice how the relict West Fork channel used to hug Atascocita Shores.
Key Map
This image shows locations referenced above for those who may not be familiar with them.
Key to locations
Do you see other things that I did not? Please let me know through the contact form on this web site.
As the dredging program moves forward, these maps may also help inform dredging strategy. Stay tuned.
Posted by Bob Rehak on 6/13/2019
653 Days after Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/50-copy.jpg?fit=1500%2C990&ssl=19901500adminadmin2019-06-13 00:32:172019-06-16 09:32:21Living Landscape: San Jacinto River Before Lake Houston and Now
GALVESTON, Texas (June 10, 2019) – The U.S. Army Corps of Engineers Galveston District staff executed a modification to the West Fork San Jacinto River Emergency Debris Removal contract June 7, 2019, to dredge an additional 497,400 cubic yards of material that was deposited in the mouth of the San Jacinto River from Hurricane Harvey.
“This contract modification will ensure a decrease in threats to critical infrastructure and lower the risk to potential loss of life,” said Charles Wheeler, USACE Galveston District project manager. “This is an ongoing contract that is part of a Federal Emergency Management Agency mission assignment.”
According to USACE Galveston District officials, the dredged material will be placed at the existing location referred to as Placement Area 2, which is located approximately 10 miles upriver. The additional dredging is scheduled to be completed by the end of 2019, with the demobilization of the equipment completed by early 2020.
No Mention of Other Partners
The press release does not mention the City of Houston, Harris County, the State of Texas, or Congressman Dan Crenshaw’s office. Most had been negotiating with FEMA and the Corps as late as last Friday.
On two previous occasions, the City announced agreements in principle with FEMA and the Corps. However, the two sides still had many details to work out relating to volume, storage, permitting and cost. The City and FEMA have tried to reach agreement on the volume of sediment deposited by Harvey since last October – eight months.
The Corps’ announcement reveals just how far apart the two sides were in their volume estimates – about 900,000 cubic yards. That difference means much of the mouth bar area will remain undredged – at least for now.
With approval to remove only about 500,000 cubic yards, the dredgers will have to cut a channel around the mouth bar, most likely on the deeper Atascocita side. Ironically, that would mean leaving behind sand deposited above water by Harvey – a decision that could confuse the public.
Today, the Great Lakes dredge has anchored near Kings Harbor. Judging by the weeds and logs in the pictures below, it appears that they will have to dredge their way TO the mouth bar. That could use up some of the precious approved volume. It could also take several weeks to position and calibrate all the equipment necessary to pump sediment 10 miles upriver.
Great Lakes Dredge has moved downriver east of West Lake Houston Parkway. It is anchored in front of Raffa’s in Kings Harbor.Wider shot taken from the pier in Kings Harbor facing west toward the Great Lakes Dredge and the West Lake Houston Parkway bridge.Callan dredge operating on the other side of the pier. Dredgers are responsible only for work in the channel, not tidying up the shoreline.While taking this shot this morning, I noticed that workers were finally starting to renovate Sharkey’s, one of the most popular restaurants in Kings Harbor before Harvey.
What Comes Next?
Pumping sediment from the mouth bar to PA-2 will require the horsepower of the larger Great Lakes dredge. It will also require several extra booster pumps and miles of additional 24 inch pipeline. The Great Lakes dredge has now moved downstream and is anchored east of the West Lake Houston Parkway bridge near Kings Harbor.
Last week, dredge pipe re-appeared under the 59 bridge after being gone for two months. That fueled rumors that the two sides had finally worked out some kind of deal. At this hour, the mystery is where does the Corps’ decision leave all the other parties in this process? More important, where does it leave the remainder of the mouth bar?
The City, Corps, FEMA and TDEM would have to increase the approved volume after the next phase starts or…
The City, County and TDEM would have to remove the rest without FEMA and the Corps.
However, money is just part of the problem. The second option might require permitting another placement area. Permitting could delay the project. But permitting a closer placement area might also save money. It gets complicated.
PA 1 is filling up rapidly as the pictures below show. And PA-2 is so far upriver from the mouth bar that would cost extra millions of dollars to use.
Tail end of the Callan dredge pipe empties sediment into an old sand pit off Townsend in Humble.Several months ago, this was all water. The owner of the pit is now selling sand to an asphalt companyand the pit is still filling rapidly.
Easy Way to Save Money
Shortening the distance between the mouth bar and the placement area could reduce the amount of diesel and manpower needed to run the booster bumps. Each booster uses more than one thousand gallons of diesel per day. So costs add up rapidly. That’s why the Corps is still considering other placement areas.
Berry Madden owns several thousand acres south of River Grove Park between the river and FM1960. According to Madden, using his property could save the government $5.5 million in pumping costs. And that’s just on the first 500,000 cubic yards. If 2 million cubic yards is an accurate estimate for the total mouth bar, using Madden’s property could save $22 million. That’s even more than the remobilization costs we were trying to save.
I hope we don’t stretch this out too much longer or make it any more difficult. My truck needs some repairs and I’m afraid, as a taxpayer, that I may not be able to afford them!
Posted by Bob Rehak on 6/12/19
652 Days after Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/BensBranch_01_01.jpg?fit=1500%2C1000&ssl=110001500adminadmin2019-06-12 12:26:022020-01-17 10:21:08Army Corps Moving Forward with Partial Mouth Bar Dredging to Reduce Flood Risk
Yet more drone footage by local resident and videographer Jim Zura of Zura Productions revealed that Elm Grove and North Kingwood Forest weren’t the only areas with flooding problems on May 7, 2019. The low-lying Romerica land is in the floodway and floodplain of the San Jacinto West Fork. A large part of the property is also classified as wetlands.
Flood Follies
May continued the developers’ long standing tradition of flooding follies.
Zura Videos Show Scope of Flooding Day After May 7
Zura filmed three short drone videos linked below. The first two from River Grove Park show the extent of Romerica’s flooding problems on May 7. The third shows street flooding on May 3 on much higher ground.
Romerica has reportedly decided to reapply for a permit from the Army Corps. As they develop the required surveys and studies coming out of Round One, they have taken down many of the websites that previously caused them so many problems. For instance, they removed the site offering EB-5 visas to foreign investors through their American Vision program. However, I have screen captures of all the suspect websites.
Zura’s video underscores the folly of developing this property into anything other than a park. I hope Mr. Haddad and Mr. Covarrubias watch these videos closely.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/Zura-RG-Romerica.jpg?fit=1500%2C838&ssl=18381500adminadmin2019-06-11 21:44:272019-06-11 21:47:25Zura Drone Videos Reveal Romerica Had Flooding Problems on May 7 Also
