Contractors Clearing South Side of Northpark Entry at US59

October 2, 2023 – Contractors finished clearing the north side of Kingwood’s Northpark entry last week. Now they have shifted their focus to the south side to make room for two stormwater retention basins that will double as decorative lakes.

TxDoT requires the basins to catch extra runoff caused by widening of the road.

Photos Show Progress of Northpark Entry Construction

The focus of the project’s landscape architects now is saving as many trees as possible. I took the photos below with one exception on 9/30/23.

Looking west. Trees remaining on the south (left) side of Northpark have been marked for transplantation. Excavation of pond on north (right) side should begin in mid-October.

In the photo below, note the rings around the remaining trees on the south side.

Those rings help retain water and nutrients being given to the trees to enhance their chances of surviving transplantation.
Looking E. Note how row of trees on the left screen the entry from the busy shopping center behind them. Also notice how the right side does not have a similar row of trees.

Landscape architects will relocate most of the remaining trees on the right/south side of Northpark to create a backdrop for the new pond. Some trees will remain in front of the pond. See the latest plan below.

Northpark entry plan

Handling Overflow from Ponds during Heavy Rains

To avoid flooding the Northpark entry area, contractors will channel overflow from the ponds west to Bens Branch and the Kingwood Diversion Ditch.

Looking east. Note clearing on the left/north side of Northpark to lay the new stormwater line that will carry overflow from the ponds to the east.
Looking west toward 59. The stormwater line will go behind Public Storage (upper left) and carry water toward the Kingwood Diversion Ditch and Bens Branch.
Northpark Drive expansion;
Route for excess water. Circle shows location of photo above this one.

Status from Diversion Ditch to 494

Looking east from Russell-Palmer to Kingwood Diversion Ditch. Virtually all of the ditch has been replaced by box culvert.
A coffer dam remains around an out-of-place water line that needs to be lowered.

Re-engineering of the water line has begun in concert with the City of Houston.

Farther east where culverts have already been placed, you can start to see how Northpark will be widened inward toward the center to create two extra lanes of traffic.
Looking west from Russell-Palmer, contractors are still waiting for Centerpoint to move a gas line out of the median to the side of the road.

Until Centerpoint moves that gas line, contractors will focus on other parts of the project, such as the entry.

Saving Money While Saving Trees

At their monthly meeting last Thursday, Lake Houston Redevelopment Authority/TIRZ board members discussed the escalating cost of relocating trees. Costs increased as trees grew between the original estimate and today.

After the meeting, Ralph De Leon, the project manager, met with contractors, the landscape architect and project designer. They developed a new plan to help hold down costs.

Previously, some trees were to be moved twice, first to a temporary holding location on the north side of Northpark and then back to their final spot on the south side. Why? Contractors needed to build up land behind the pond on the south side of Northpark before transplanting the trees.

The new plan calls for building up the land before moving ANY trees. That will eliminate the cost of the double move. It will also reduce traffic disruption. Tree moving equipment will no longer have to cross Northpark.

Main Goals of Northpark Project

Overall, the main goals of the Northpark project include:

  • Widening the road to reduce delays caused by increased traffic
  • Building a bridge over the UP railroad tracks to eliminate traffic blockages
  • Creating a reliable, all-weather evacuation route for Kingwood

For More Information

For previous posts about Northpark construction, see the following:

Also visit the Lake Houston Redevelopment Authority/TIRZ 10 Project pages at

Posted by Bob Rehak on 10/2/23

2225 Days since Hurricane Harvey

Entire Texas Republican Congressional Delegation Urges Abbott, Paxton to Investigate Colony Ridge

A letter dated September 30, 2023, and signed by all 25 members of the Texas Republican Congressional delegation urged Gov. Greg Abbott and Attorney General Ken Paxton to investigate numerous allegations related to Colony Ridge in an upcoming special session of the Texas Legislature. The Colony Ridge developer has already launched a charm offensive designed to defeat what it calls “scurrilous rumors and lies.”

Congressional Letter Suggests Scope of Investigation

The controversial Liberty County development has drawn media attention dating back to at least 2015. The letter by Texas Congressional Republicans refers to many of those. Allegations in the letter include:

  • “Owner-financed loans with no credit check or proof of legal residency, making the location an optimal haven for illegal aliens amid a historic border crisis.”
  • Public safety concerns, including creating a “no-go zone” for law enforcement
  • Sewage spills
  • Fecal contamination in drainage ditches
  • Significant erosion in drainage ditches leading to increased risk of downstream flooding
  • Adverse effects on neighboring communities
  • Unsuccessful local attempts to remediate issues
  • Lack of fire hydrants
  • Improvised living conditions
  • Water, power and flooding issues
  • Violent crime including several high profile murders
  • The largest drug busts in the history of Liberty County
  • Drug cartel activity
  • Overwhelming the Cleveland ISD with “thousands of illegal aliens.”

The letter concludes with:

  • A list of things that the Congressional Republicans have fought for at the federal level to make America secure.
  • A request for Abbott and Paxton to share the results of their investigations with Congress.
  • An offer to assist the state.

Since media attention to Colony Ridge has mushroomed, claims like those above have become harder and harder to brush off – especially in an election year, when Republicans have framed illegal immigration as a core issue.

To see the full, six-page, footnoted letter, click here.

Will Investigation be Instant Replay of Paxton Impeachment Trial?

Ironically, Paxton’s office will theoretically do the investigating. His recent impeachment trial centered around his relationship with a developer (but not this one). It will be interesting to see how/whether that affects this investigation. Only one thing is certain: Paxton, Abbott and Colony Ridge will be under a national spotlight.

Colony Ridge Developer Launches Charm Campaign

The developer also released a letter, one day ahead of the Congressional letter. (See below.) It calls the allegations “salacious lies and rumors.” It offered to give members of the Texas legislature tours of Colony Ridge in advance of the upcoming special session. I’m sure the tours will be heavily curated. For instance, I doubt they will:

  • Go down streets with horrific living conditions
  • Highlight their lack of fire hydrants
  • Show off sewage spills
  • Point out the bridge they blew out on FM1010
  • Highlight the repossession rate of property (I talked to one owner of a new lot who was the fourth owner.)
  • Tour eroded channels (that would require maintenance roads at a minimum).

Here’s the Colony Ridge letter.

Notice that the developer’s letter does NOT deny drainage problems.

Complies with All Regulations? Really???

I was not invited to the developer’s party. But any member of the Texas legislature who wants to see whether they comply with Liberty County regulations can consult these posts.

When I first started exploring Colony Ridge, I learned that Liberty County did not have construction plans, nor required drainage studies for many Colony Ridge subdivisions. And those that the County could supply underestimated the runoff from Colony Ridge by misrepresenting the soil types found there. The extra runoff blew out FM1010 which remains unrepaired as of this writing.

Colony Ridge also failed to meet fire-hydrant spacing and pressure requirements in the Liberty County Fire Code. I have ten fire hydrants on my block. At last count, Colony Ridge had 59 in an area 50% larger than Manhattan.

If you want to see an example of their “fully engineered” sewers, see this post. But hold your nose.

This post explores more Colony Ridge issues and impacts…

Posted by Bob Rehak on October 1, 2023

2224 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.

Where Flood-Mitigation Dollars Have Really Gone

An analysis of Harris County Flood Control District (HCFCD) and partner spending since 2000 reveals striking contrasts between watersheds in terms of where flood-mitigation dollars have gone.

Watersheds vary as much as 130 to 1 since 2000 and almost as much since Harvey. Most watersheds remained relatively constant in the rankings during the different time periods. However, a few have shifted up or down a few positions as land was acquired for projects or construction kicked off.

Data below includes spending by HCFCD and its partners from 1/1/2000 to 6/30/2023.

Main Takeaways from the Data

The big stories:

  • Since 2000, the top four watersheds received more flood-mitigation dollars than all 19 others put together. The top four include: Brays, Greens, and White Oak Bayous, and Cypress Creek.
  • Since Harvey the top four received 48%.
  • The distribution of funds continues to show the impact of Harris County’s Equity Prioritization framework.

Harris County’s Equity Prioritization gives weight to race and low-income areas, but not flood damage, the severity of flooding, or protection of infrastructure.

San Jacinto Gets Above Average Damage, Below Average Funding

The San Jacinto ranks below the averages (before 2000 and since Harvey) for flood-mitigation dollars – despite ranking 8th in damaged structures among all 23 watersheds. Damage totals include five major storms (Allison, Memorial Day, Tax Day, Harvey and Imelda).

Compiled from HCFCD Federal Reports

Watersheds Ranked by Funding Since 2000

Here’s how the funding looks in graphs and tables. All data was obtained from HCFCD via FOIA requests.

Data obtained from HCFCD via FOIA requests. Includes Harris County and partner spending.

Here’s the actual data if you want to see exactly how much your watershed received.

From 1/1/2000 through 6/30/23

Watersheds Ranked by Funding Since Harvey

Now let’s look at the how spending shifted after Harvey. Not much, at least relatively speaking.

Includes Harris County and partner spending. San Jacinto climbed two spots, but it is still barely above the median and far below the average.

Here are the actual totals for each watershed shown in the graph above.

Spending from 17Q3 to 23Q2 inclusive.

Feet above Flood Stage

Now let’s look at the severity of flooding. The chart below measures feet above flood stage at different Harris County gages.

Flood Stage is the level at which a river, stream or channel comes out of its banks.

I compiled this chart from data in the Harris County Flood Warning System website.

That 20+ feet above flood stage at the San Jacinto West Fork and US59 was the highest I found in the county.

Damage to Infrastructure

That 20+ feet destroyed Kingwood College, Kingwood High School, all of the businesses in Kingwood Town Center and Kings Harbor, the southbound lanes of US59, the Union Pacific Railroad Bridge, Memorial Hermann’s new Convenient Care Center, sewage treatment plants, and a senior housing complex.

Lone Star College
Harvey flooded 6 of 9 buildings at Lone Star College/Kingwood. Repairs cost a total of $60 million.
I-69 damage and repairs
I-69 Bridge replacement after Harvey. Repairs took 11 months creating massive delays and detours.
UP Bridge
Union Pacific Railroad Bridge that parallels US59 was destroyed and required complete replacement.
Alspaugh’s Hardware during Harvey
New HEB shopping center 1.5 miles from the San Jacinto West Fork was under more than 7 feet of water during Harvey.

Six years after Harvey, many of the commercial areas in Kingwood still haven’t fully recovered. Anchor stores remain empty in three of five shopping centers on Kingwood Drive between Town Center and US59.

Achieving True Equity

While I’m sympathetic to the plight of poorer neighborhoods, I cringe at the self-serving definition of equity used by a Democratic-dominated Commissioners Court to deny funding to the hardest hit area in the county.

We need a system that’s fair to all, not just some. Anything less will perpetuate racial distrust. This is a public safety issue and public safety should not be politicized.

Posted by Bob Rehak on 9/30/23

2223 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.

Will We See Fujiwhara Effect? Twin Spin in Atlantic

Weather buffs could soon be treated to a rare event: the Fujiwhara Effect. That’s when one tropical storm collides with another. Topical Storm Philippe is being overtaken by the newly formed Tropical Storm Rina. See the satellite image below taken around 12:30 PM CDT.

12:20 pm Houston time
Two hours and forty minutes later.

Will They Merge?

I asked Harris County Meteorologist Jeff Lindner what happens in such a case. His response:

“Generally speaking the weaker system will rotate around the stronger system. This is known as the Fujiwhara Effect.”

Harris County Meteorologist Jeff Lindner

Wikipedia offers a great description of this rare event and some of the parameters necessary for it to occur.

“The effect occurs,” says Wikipedia, when two nearby cyclonic vortices move around each other and close the distance between the circulations of their corresponding low-pressure areas. The effect is named after Sakuhei Fujiwhara, the Japanese meteorologist who initially described the effect. Binary interaction of smaller circulations can cause the development of a larger cyclone, or cause two cyclones to merge into one. … Tropical cyclones typically interact within 870 mi. of each other.”

These storms are already within that radius. At this hour (3:30 PM CDT on 9/28/23), the centers of Philippe and Rina are 631 miles apart, but their outer bands are already interacting as you can see in the photos above. And the effect will likely become stronger.

Philippe (left) is moving at 2 mph and Rina at 10 mph. So they will come even closer.

Cones of Uncertainty

The two maps below show projected tracks for the next few days. But remember, the center of the storm has an equal chance of passing through any point within the cone of uncertainty.

Here’s the cone for Philippe.

Here’s the cone for Rina.

Pick a spot on the grid and compare the projected locations over time.

Wikipedia says, “Rotation rates accelerate when tropical cyclones close within 400 mi of each other. Systems typically merge when they are within 190 mi of one another.”

So we have at least a few days to watch these two and a developing Fujiwhara effect if any.

At an 8 mph closing rate, two storms 631 miles apart would take about 2.5 days to get within 190 miles of each other.

How to See if They Merge

Mergers are fairly rare, according to Wikipedia. But these two could tango. So watch to see if they merge over the next few days. Exact predictions are difficult, because of the uncertainty associated with storm tracks.

However, you can check their progress and proximity visually by looking at the satellite images on NOAA’s National Hurricane Center website. Select from several different options within the “Atlantic-Wide View”: Geo-Color, Visible, Short Wave IR, Infrared, and Water Vapor.

Regardless of what happens, NOAA does not predict that these storms will come anywhere close to Texas. So sleep easy.

Posted by Bob Rehak on 9/28/23

2221 Days since Hurricane Harvey

For Better Flood Mitigation, Let’s Dig a Little Deeper

When I say “dig a little deeper” to improve flood mitigation, I’m speaking metaphorically, of course.

On September 17, 2023, Jim Blackburn, a lawyer and professor of environmental law in the Rice University engineering department, published an article in the Houston Chronicle. He titled it, “What Houston’s next mayor needs to do about flooding.”

Both Prof. Blackburn and the Chronicle labeled the article “opinion.” That’s fortunate because in some areas, Blackburn made assertions contradicted by facts. In most other areas, he made high-level recommendations without any specifics.

For example, among other things, Prof. Blackburn argues that Houston’s next mayor should:

  1. Build more mitigation projects for Halls and Greens Bayou Watersheds, which he says haven’t received their fair share.
  2. Address climate change with better planning and engineering tools.
  3. Speed up buyouts.

Let’s examine each and why we all need to dig a little deeper if we want to improve flood mitigation.

Halls and Greens Bayou Watersheds

Both Halls and Greens watersheds HAVE received mitigation projects. Many. And more than their fair share. You can see it in spending data and on the ground. However, Harris County Flood Control District has delivered the projects, not the City of Houston. 

HCFCD and its partners have spent more than $390 million on Greens and Halls mitigation improvements since 2000. Greens has received more dollars than any other watershed except Brays (where Rice is). And tiny Halls ranks third in dollars per capita among all watersheds.

Professor Blackburn and his graduate students need to dig a little deeper. They should get out more and smell the construction dust. For example, here is a new Halls Bayou detention basin, one of many built in the watershed during the last 10 years

New Halls bayou detention pond
New Halls Bayou Detention Basin west of Keith Weiss Park, photographed in March 2022.

Then, there’s this new detention basin along Greens Bayou at Cutten Road under construction in 2021. Again, it’s one of at least a half dozen built in the last ten years along Greens.

Cutten basin
One portion of the massive Cutten Road stormwater detention basin on Greens Bayou

I compile flood-mitigation funding by watershed through quarterly FOIA requests. I also cross-check the data by photographing construction from the air.

Photos such as those above support the spending reported below. However, neither the photos nor the spending data fit the current, popular political narrative about “historical disinvestment” in low-income minority neighborhoods.

Includes both Harris County and partner dollars

Of the top five watersheds above, four have a majority of low-to-moderate income residents; only Cypress Creek does not. Those five watersheds have received 60% of all funding going back to 2000, compared to 40% for the other 18 watersheds put together.

From high to low in the graph above, spending varies by 130X. Such data shows that many watersheds have been historically deprived – in the name of “equity.” But those deprived tend to be on the more affluent end of the spectrum.

Address Climate Change with Better Planning and Engineering Tools

Next, Professor Blackburn wants to address climate change with better planning and engineering tools. It’s hard to see what more the next Mayor of Houston could do in this regard. 

Professor Blackburn asserts that we need to “understand our changed rainfall patterns and integrate that knowledge into every aspect of the City’s thinking.” 

Since Harvey, the City has already adopted NOAA’s new Atlas-14 rainfall-probability statistics and incorporated them into its regulations. So, design professionals are already working on new, updated assumptions.

Plus, NOAA is currently working on Atlas 15 which predicts future impacts of climate change. But NOAA won’t release those stats until 2027 at the earliest – after the next mayoral election.

Professor Blackburn, a reputed expert, doesn’t define how climate is changing, but asserts that professionals should consider the changing patterns. He believes they should engineer “streets, sewage treatment plants, underground and above-ground stormwater systems, floodplains and general drainage flow patterns” with the unspecified climate patterns in mind.

It’s hard to argue against progress. But the real issue, in my opinion, is that leaders in many surrounding cities and counties have not yet uniformly adopted NOAA’s Atlas 14 standards. Perhaps the next Mayor could jawbone them into sending less water downstream

The Mayor could also discourage large increases in impervious cover under proposed programs such as the Houston Planning Commission’s so-called Livable Places. Livable Places would disproportionately increase flood risk for low-income and minority neighborhoods because of the program’s linkage to mass transit.

Speed Up Buyouts

Blackburn believes that buyouts should happen faster after a flood – before people rebuild. Most people agree that the process needs streamlining. But how?  

Experts have proposed multiple improvements. However, none has gained traction across the board with local, State, and Federal lawmakers. 

For instance, after Harvey, Harris County Flood Control executives pitched plans in Austin for a QBF (Quick Buyout Force). Instead of waiting for:

  • The President to declare a disaster
  • Congress to vote funds
  • FEMA to design rules for disaster relief
  • The State to adopt them
  • Local agencies to identify eligible recipients and solicit applications
  • Local, State and Federal authorities to review and approve the applications, and 
  • Money to flow through the pipeline…

…HCFCD argued for pre-approval of guidelines and to have a pot of funds available before disaster strikes, kind of like a savings account for a rainy day. Money could then be used immediately. Local agencies would later reimburse the Federal government for money they didn’t use.

Houston’s next Mayor could throw his/her influence behind such a plan or a suitable alternative.

Unfortunately, Prof. Blackburn doesn’t recommend a plan. Nor does he dissect each issue and give us the benefit of his wisdom. With all the brainpower and resources at his disposal, he could make a genuine contribution to the community. Perhaps his future opinion pieces will elucidate how we should improve beyond simply preparing for the future. 

Collectively, we all need to dig a little deeper to improve flood mitigation. We need to start with facts and get down to specifics.

Posted by Bob Rehak on 9/27/2023

2220 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.

Funding Announced for Massive Detention-Basin Complex on Cypress Creek

9/25/23 – Approximately 425,000 people live in the 204 square mile Cypress Creek watershed which has severe repetitive flooding. At a press conference this morning, County, State and Federal officials announced $50 million in funding for a massive complex of stormwater detention basins on Cypress Creek at T.C. Jester Blvd. to help protect those people.

The basins will span approximately 150 acres on both sides of T.C. Jester and include 1200-acre feet of planned stormwater detention capacity, wet bottoms, and recreational trails.

Approximate boundaries of three detention basins – one will go west of TC Jester and two more east. White area is existing basin.

Altogether, the stormwater detention capacity in this area will increase approximately 75X.

Google Earth calculation of existing and planned ponds

The existing pond covers approximately 2 acres and the new areas will cover more than 150.

Looking E over T.C. Jester. Existing 2-acre basin in foreground was site of press conference. Wooded area beyond will become two new detention basins.

Thanks to County, State and Federal Governments

The $50 million will come from three primary sources:

Harris County Flood Control District Executive Director Tina Petersen also reminded everyone of the money designated for Cypress Creek in the Flood Bond, which was considerable.

The GLO/HUD money has been requested but not yet confirmed although all indications are positive at this time. GLO Commissioner Dawn Buckingham has committed to making sure that people in all parts of Harris County benefit from the $750 million.

Timetable and Project Scope

HCFCD Director Dr. Petersen addressed the next steps in the projects. “A portion of the projects on the east side of T.C. Jester will start construction in the next 6 to 9 months. The remainder should go into construction no later than the end of 2024. So we’re going to see these projects move quickly. This type of progress would not have been possible without the critical funding that our Congressman and Representative secured “

The overall project includes three stormwater detention basins within a broader footprint. Two basin compartments are on the east side of T.C. Jester Boulevard and another is on the west side.

Excavation of the west side basin (see below) has already begun under an E&R (Excavation and Removal) Contract. A private contractor is removing the dirt, almost free of charge, then selling it at market rates to recoup costs and make a profit. An estimated 120,000 cubic yards of material has already been excavated to date.

Work to date on basin west of T.C. Jester. Looking N toward Cypresswood Drive.

The contractor began removing dirt in the general area to get a head start on construction, even before final design of the basin. The final design will begin soon.

Each basin will have a wet-bottom with maintenance berms, side slopes and high banks along the outside.

Construction for all basins should begin no later than Q4 2024. They have estimated 8-month construction timelines.

Extent of Benefits

The three stormwater detention basins will work together – taking stormwater from the main stem of Cypress Creek and holding it until water levels recede on the main stem.

The projects will also have recreational benefits such as hike and bike trails.

Director Petersen stated that the projects will primarily benefit the local area, i.e., benefits will not extend very far downstream. The 1200 acre feet will likely take several thousand homes out of the floodplain.

Even though those homes will be in the Cypress Creek area, 1200 acre feet being held back upstream is 1200 acre feet that won’t be in the living rooms of Lake Houston Area residents during the next big flood.

More to Come

Ramsey also pointed to more projects to come, though he didn’t elaborate. He said, “This is $50 million of the $100 million that will be spent over the coming months in the Cypress watershed. So hold on. We’re getting started. This isn’t the end. This is the beginning.”

Speakers at T.C. Jester Detention Basin Press Conference included U.S. Representative Dan Crenshaw, State Representative Sam Harless, Harris County Precinct 3 Commissioner Tom Ramsey P.E., and HCFCD Executive Director Dr. Tina Petersen.

Posted by Bob Rehak on 9/25/2023

2218 Days since Hurricane Harvey

Review: Urban Flood Risk Handbook

The World Bank recently published the 177-page Urban Flood Risk Handbook: Assessing and Identifying Interventions by Scott Ferguson, Mathijs van Ledden, Steven Rubinyi, Ana Campos, and Tess Doeffinger.

The book is primarily targeted to flood-project managers and city officials. However, the informative illustrations and easy-to-understand writing make it a useful primer for anyone who wants to become more knowledgeable about flooding.

The World Bank bills the handbook as a “roadmap for conducting an urban flood risk assessment in any city in the world.”

What will the average person get from it? The ability to understand flood professionals, the issues they face, and how they evaluate problems/solutions.

It also made me realize that Harris County’s equity framework, which the county uses to allocate flood-mitigation funds, fails to incorporate many factors recommended by the Department of Homeland Security and others.

Outline of Handbook

The book contains five chapters.

Chapters cover the following sub-topics.

Intro and Chapter 1: Defining Risk

Much of the book has a checklist quality to it. For instance, what should professionals quantify when defining flood risk?

  • Hazards and their probabilities
  • Exposure – an inventory of elements and activities affected by hazards, for instance:
    • The population and its assets such as homes and belongings, private businesses, and industrial assets
    • Infrastructure such as roads, drinking water, sanitation, drainage, and flood protection infrastructure
    • Public infrastructure like health care and school facilities
    • Environmental and cultural assets
    • Economic activities.
  • Vulnerability – the degree to which people, property and infrastructure can be adversely affected

Here, for instance, I was surprised to learn that Harris County’s equity framework considered some, but not all of the factors that make areas vulnerable. For instance, it doesn’t really incorporate infrastructure!

Chapter Two: Hazard Assessment

The chapter on Hazard Assessment begins with a list of “boundary conditions” typically used within a flood model.

Five conditions typically include: (1) rainfall, (2) infiltration, (3) flow, (4) water levels and waves, and (5) pumps and flow control structures.

But just measuring rainfall can be difficult depending on the number and types of gages in use. “Most meteorological services only provide daily values (mostly from manual gauges), which provide part of the overall rainfall characteristics. However, the distribution and intensity within a single day are essential,” say the authors.

Automated gages that can measure short (sub-daily) periods are critical in informing regulations that affect the design of infrastructure. Short, high-intensity bursts are a significant factor in urban flooding. However, many areas have gages measured manually once per day. (The Flood Control District’s are all automated.)

As I scanned the text of this chapter, flashbacks from Harvey kept recurring. When I read this sentence, I thought of the Lake Conroe discharge designed to prevent the flooding of Lake Conroe homes. “Discharge rates from control gates normally relate to both upstream and downstream water levels…” [Emphasis added.] Did the dam operators consider downstream water levels at the time? The case is still pending in the courts.

In chapter 2, I also found the most illuminating discussion of differences between 1D, 2D and 3D modeling that I have ever read.

Ditto for a description of Manning’s Coefficient, which is used to estimate the impact of friction on the speed of water, which in turn affects the rate of accumulation and flood height.

Illustration of Mannings Roughness Coefficient and friction’s impact on speed of floodwater.

Trees and buildings create friction for floodwater that slows it down. But concrete and clear-cutting speed it up.

Such information is used to quantify the potential consequences of flooding to homes, businesses, and people across an area.

Chapter 3: Risk Assessment

Chapter 3 focuses on Risk Assessment and lists types of infrastructure that the Department of Homeland Security defines as “critical sectors.”

Again, Harris County’s Equity Framework (used to distribute flood-mitigation funds) considers none of these.

Chapter 4: Interventions

Chapter 4 discusses types of interventions (solutions to flooding). They fall into three main categories.

The chapter then addresses the limitations, applicability, costs, benefits, and environmental/social impacts of each.

It’s too complicated to summarize here. But it’s fascinating to see how flood professionals evaluate the range of options.


The last chapter addresses the business side of flood mitigation, i.e., bidding jobs. I’ll skip that here and close by saying this. Even after studying flooding for six years, I felt lights turning on almost every time I turned a page in this book.

I had a high level understanding of most of the concepts. But this gave me a much fuller understanding. I found myself constantly thinking, “Aha, so that’s how that fits in.”

And it’s a free download!

Kudos to the World Bank and the authors. They have provided a valuable addition to the literature.

Posted by Bob Rehak on 9/24/23

2217 Days since Hurricane Harvey

Used with permission of World Bank

Northpark Entry Plan Balances Flood Mitigation, Saving Trees, Cost

Social media has been abuzz this week about the Northpark Drive entry to Kingwood. As contractors removed trees from the north side of the road to make room for a detention pond, many people complained.

But it’s important to remember why we’re improving Northpark: to accommodate increased traffic and to create a reliable, all-weather evacuation route. In that regard, the Lake Houston Redevelopment Authority (LHRA) must balance three conflicting needs: flood mitigation, saving trees and cost. Let’s look at how each relates to the objectives.

Reliable, All-Weather Evacuation Route

During Harvey, Hamblen Road, Kingwood Drive and Northpark were all blocked by rising floodwaters. That forced many people to try to snake out of Kingwood through Porter…if they could get there. Many couldn’t.

For decades, we’ve also worried about the possibility of a train disaster that could block off Kingwood’s exits. The longer trains that Union Pacific runs now can block multiple exits simultaneously. The longest trains stretch for more than three miles. And if there were a derailment or toxic spill, it would be difficult getting people to safety.

Raising the elevation of Northpark between Bens Branch and the Kingwood Diversion Ditch eliminates the first problem. And building the bridge over the tracks at 494 eliminates the second.

Finally, widening the road will enable more vehicles to evacuate faster.

Flood-Mitigation Enhancements

All that extra concrete to expand the road, however, reduces rainwater infiltration and increases runoff. To keep the road from flooding, engineers calculated they needed 22 acre feet of stormwater detention capacity near US59.

The solution: build two permanent ponds, one each on the north and south sides of 59 where the groves of trees were. TxDoT already owned the land. So it was available at no cost.

Looking N toward Kroger Center. Clearing for N pond completed. Clearing for S pond (bottom right) begins next week.

Water will permanently fill the ponds, just like those at Kingwood Drive. The difference between the normal water surface elevation and the lip of the ponds will equal 22 acre feet. The size of the ponds will keep that gap at an aesthetically pleasing level.

Looking S. Note the protective fencing around the remaining trees. Additional trees may be stored temporarily in the foreground.

Said another way, the ponds will look like decorative enhancements but serve a vital purpose that few realize.

The outline you see in the photo below will match the perimeter of the pond.

No more trees will be cut for this pond. The area cleared represents the final outline of the pond.

The layout below shows how the ponds should look when completed.

For a more legible, high-res version, click here.

Saving Trees

According to Ralph De Leon, project manager, “Enough trees will remain to form a pleasing backdrop for the pond, screen the visually noisy area behind them, and create a good first impression for visitors.”

From 30 feet, you can barely see the shopping center behind the trees. From ground level, it will be completely screened.

It’s important to remember that when KSA revised the Kingwood entries after TxDoT widened 59, many people wanted ponds at Northpark. They complained that KSA was neglecting Northpark compared to Kingwood Drive.

Many trees are being transplanted. But that’s an expensive proposition; the trees have grown since LHRA first prepared estimates two years ago.

“We’ve already identified the trees that will be saved,” De Leon continued. “Some will move to their permanent location immediately. Others will be stored temporarily at staging locations until the road construction gets further along. Then they’ll be moved to their permanent positions.”

The landscape architects, contractor, and LHRA are evaluating each tree individually. Their objective is to save as many as possible. But dollars pose a constraint.

Cost Limitations

De Leon also says “The cost to move each tree is roughly $11,000. We can’t afford to move the truly huge trees. They cost up to $100,000 per tree. And we just don’t have a budget for those.”

Machines like these will move trees that range from 4″ to 17″ in diameter. Photo courtesy of Davey Tree Company.

To maximize aesthetics, the Redevelopment Authority will relocate a mix of trees, such as oaks and pines.

The trees that will move have already been inventoried and tagged.

Update on Water-Line and Utility Conflicts

In my last Northpark post, I pointed out two conflicts holding up construction of the median farther east – one with a water line to a new church near Russell-Palmer Road and a second with CenterPoint.

The City of Houston has agreed to let the Redevelopment Authority’s contractor design a workaround for the water line that interfered with the placement of box culverts. Contractors left a gap big enough for two sections of culvert and a coffer dam to keep dirt from collapsing into the hole.

Because the culvert is tongue-in-groove, contractors also left enough room for a collar. That will allow the two new sections to slide into place. It will also prevent leaks in any gap that remains.

Regarding the CenterPoint gas line running down the center of the ditch at different depths, CenterPoint decided to move the whole line out of the culvert to the south side of the road. Inbound drivers may notice long lengths of welded blue pipe stacked up between Russell-Palmer and Kings Mill. That’s what that is for.

Next Steps

Contractors will start removing trees for the south entry pond at 59 during the week of 9/24/23. Here is the latest revised schedule. Check back often for more updates as they happen.

Posted by Bob Rehak on 9/23/23

2216 Days since Hurricane Harvey

GIS Data Reveals Likely Source of NE Houston Flooding Unrelated to Historic Disinvestment

In northeast Houston, where residents and activists frequently chant “historic disinvestment,” I accidentally stumbled onto a much more likely cause of the frequent flooding than systemic racism. It happened while browsing a GIS database with hundreds of layers containing a broad range of information. The instant I saw it, it unlocked a mystery. Tumblers suddenly aligned that unlocked the mystery. But let’s start this story with accusations that made no sense to me.

Accusations of Systemic Racism Not Supported by Spending Data

Three years ago, I joined the Harris County Community Flood Resilience Task Force. Ever since, I have heard a constant drumbeat of “historic disinvestment” by many members who believe they are victims of systemic racism by Harris County Flood Control District (HCFCD).

They claim that they aren’t getting their fair share of flood-mitigation funds when, in fact, financial analysis reveals the opposite. They get the lion’s share.

LMI vs. Non-LMI flood-mitigation funding
LMI vs. Non-LMI flood-mitigation funding through Q3 2021.

Eight watersheds with a majority of low-to-moderate income residents have received almost two thirds of the funding going back to 2000. That’s out of a total of 23 watersheds. The money has flowed to damage – as it should.

Many people, however, don’t believe that. The loudest complaints have come from the Northeast Action Collective. They waged a battle to remove flood-control executives from office who were working tirelessly on their behalf.

Regardless, falsehoods repeated often enough eventually rose to the level of “accepted truth.” Even experts can be fooled. Jim Blackburn, the renowned professor of engineering at Rice, repeated the “historic disinvestment” claim without presenting any proof in a Houston Chronicle story last week.

He claimed residents of Halls and Greens Bayou watersheds weren’t getting their “fair share” of flood mitigation money. In fact, Greens Bayou ranks #2 in terms of money received. Only Brays Bayou has received more.

Spending by Watershed from 2000 through 2023Q1. Source: Harris County Flood Control District via FOIA request.

And tiny Halls Bayou ranks #2 in spending per capita. Together, the two bayous have received more than $390 million to date.

And they could soon receive another $466 million out of the $750 million that the GLO and HUD recently granted Harris County for flood mitigation. If HUD approves the recommended projects totaling $466 million, Halls and Greens will have received $856 million – far more than any other watershed. (Technically Halls is a sub-watershed of Greens, but HCFCD tracks spending as if it were separate.) This is hardly historic disinvestment.

More Likely Cause of Flooding Overlooked by Critics Crying Racism

Today, while learning a new (to me) geographic information system, I randomly clicked on a “wetland” layer. Boom! Guess where the largest concentration of wetlands in Harris County is. The northeast!

Note Lake Houston in the upper right, once home to untold acres of wetlands before the dam was built in the 1950s.

As a reminder of what these wetlands once looked like, see the photos of Emily Murphy who kayaks along the shores of Lake Houston.

Emily Murphy wetland photo by Lake Houston
Photo Courtesy of Emily Murphy

Regulations discourage building in wetlands for good reasons. Water collects there. The soil is less permeable. They are low, poorly drained, and unstable.

In addition, USGS points out the many positive benefits of wetlands. “Wetlands provide habitat for thousands of species of aquatic and terrestrial plants and animals. Wetlands are valuable for flood protection, water quality improvement, shoreline erosion control, natural products, recreation, and aesthetics.”

But because they’re cheap land and available, some less-than-scrupulous developers often try to build in them. I’m told by engineers I trust that that has always been the case and always will be.

Back in the 1950s, farms and ranches occupied most of the northeast Houston area. Here’s what it looked like then.

Note the San Jacinto River in the upper right in this 1953 pre-Lake Houston aerial image from Google Earth.

And here’s what the same area looks like today.

Note the presence of Lake Houston in the upper right in this 2022 image.

There are still big undeveloped areas in the image above. But many developments have also filled in large parts of the northeast that were once wetlands in the 1950s image.

Dangers of Building Over Wetlands

According to USGS, “Wetlands are transitional areas, sandwiched between permanently flooded deepwater environments and well-drained uplands, where the water table is usually at or near the surface or the land… The single feature that most wetlands share is soil or substrate that is at least periodically saturated with or covered by water.”

Wetlands are almost always terrible places to build houses.

Four years ago, I posted about the disadvantages of building over wetlands. Pictures of the Woodridge Village property, then under development by Perry Homes, dramatized how unstable the soils were. Dangers of building over wetlands include shifting slabs, cracked driveways, mold, erosion, clogged storm drains, flooding and more.

Unsuspecting buyers of former wetlands can literally get sucked in by low prices. Seventy years later, the original builders and buyers are long gone. And pre-digital soil samples and drainage analyses (if they were ever done) have long since disappeared into the fog of history or a dusty warehouse.

Wetland-mitigation banks near a development should raise red flags to buyers today. There’s one on the northeast corner of Beltway 8 along, you guessed it, Greens Bayou. There are also two in Colony Ridge: the Houston-Conroe and Tarkington Bayou Mitigation Banks.

In conclusion…

Today’s residents in such areas pay for previous owners’ lack of knowledge – not because of historic disinvestment.

I’m not saying early owners didn’t exercise due diligence. We just didn’t know then what we know now.

Posted by Bob Rehak on 9/22/23

2215 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.

History of Heartbreak: A Colony Ridge Chronicle

I wrote my first post about Colony Ridge in May 2020. Since then, I have written more than 60 about the controversial, Liberty County colonia that’s now 50% larger than Manhattan. Virtually all of them cover aspects of drainage, wetlands and flooding, as well as the development’s impact on people, the environment and surrounding areas.

The articles also include stories on surrounding developments by the same developer, but operating under different names. But you do not need those to support the 50% larger calculation above.

I’m listing all of my Colony-Ridge-related stories here to make them easier for readers to find.

Colonia Now Drawing National Attention

During the past 3+ years, the growth of Colony Ridge, an unincorporated development, has overwhelmed smaller incorporated areas around it such as Plum Grove and Cleveland.

As a result, fast-growing Colony Ridge has attracted national attention by numerous journalists, not all of it welcomed by the developer. My focus has been almost exclusively on flooding, drainage and water quality issues. Other journalists have focused on crime, cartels, drugs, illegal immigration, overwhelmed schools, predatory lending practices, evictions, the marketing practices of the developer and more.

Here is a list of the drainage related articles. I’ve also taken thousands of pictures – far too many to insert them all here. But I have included a few. See more when you follow the links below.


Colony Ridge erosion
Due to failure to follow drainage regulations, erosion is eating people’s yards. Note gap under new fence.

May 3, 2020 Development Watchlist: Perry, Romerica, Colony Ridge and More

June 14, 2020 Rapid Runoff from World’s Largest Trailer Park Wipes Out Plum Grove Road in Liberty County and More

June 15, 2020 World’s Largest Trailer Park Has Only a Handful of Fire Hydrants

June 19, 2020 “The Developers Are Coming! The Developers Are Coming!”

June 23, 2020 48,000 Gallons of Fecal Contamination Found in Liberty County’s Colony Ridge Ditches, Streams; Problems Persist

June 24, 2020 Hidden Cost of Fecal Contamination: Removing It

October 14, 2020 TCEQ Fines Quadvest for 48,000 Gallon Sewage Spill in Colony Ridge

October 15, 2020 Plum Grove Sues Colony Ridge Developer Over Floodwater, Sewage Leaks

October 16, 2020 TCEQ Blasts Colony Ridge, Says Construction Practices Could Adversely Affect Human Health

October 22, 2020 How Loss of Wetlands Led to War

October 25, 2020 New Drone Shots Reveal Need for Better Flood Control in Liberty County

November 12, 2020 Flood Notes: Highlights of Current Happenings

November 20, 2020 Friday Flood Digest

November 27, 2020 Colony Ridge Declares War on Investigative Journalist, Too

December 1, 2020 Flood of Foreclosures: Hundreds to Lose Colony Ridge Homes Tomorrow

December 5, 2020 Colony Ridge Ditches Violate Liberty County Drainage Standards

December 7, 2020 Merry Christmas from Colony Ridge

Merry Christmas from Colony Ridge
I took this shot shortly before Christmas. Poverty in Colony Ridge is heartbreaking. Note the food still on the table. Residents say multiple families often live in such a home.

December 10, 2020 Rivers of Mud: Largest Development in Liberty County Openly Flaunts Drainage Regulations

December 12, 2020 Rivers of Mud, Part Dos: Wayne Dolcefino Uncovers More Liberty County Dirt

December 14, 2020 Liberty County Strategic Plan … Dead On Arrival

December 16, 2020 Liberty County Hazard Mitigation Plan Contains No Mention of Largest, Most Vulnerable Community in County

December 21, 2020 “One of the Best Land Developers in Liberty County”

December 23, 2020 Preserve What Makes Lake Houston Area Unique

December 26, 2020 Colony Ridge Drainage Reports Misrepresent Soil Types, Underestimate Runoff; Many Reports Missing

December 29, 2020 When Developers Claim No Detention Ponds are Necessary…


Colony ridge erosion
Dirt often piled by the sides of ditches erodes back into the ditches and gets carried downstream. There, it can reduce conveyance and must be dredged to control flood risk.

January 2, 2021 Guess Which Way to Colony Ridge

January 3, 2021 Flooding of the Fifth Kind: By Government Neglect

January 4, 2021 Liberty County Launches Major Investigation into Colony Ridge Irregularities

January 10, 2021 New Wetland Mitigation Bank Proposed for Areas Upstream from Lake Houston

January 11, 2021 Thousands of Acres in East Fork, Luce Bayou Watersheds to be Developed as Part of Kingland

January 17, 2021 Rosemay Fain’s Harvey and Imelda Stories

February 1, 2021 Colony Ridge Developer Sues Critics For More Than Million Dollars Based on Questionable Allegations

March 6, 2021 Photo Essay: How “Backslope Interceptors” Reduce Erosion, Ditch Maintenance, Flood Risk

April 23, 2021 Silence: Liberty County, Colony Ridge, Landplan Engineering Remain Mute on Missing Documents

April 25, 2021 Officials Slapped With Criminal Complaints for Failure to Produce Records in Colony Ridge Investigation

May 3, 2021 Rampaging East Fork Floodwaters Cut New Path Through Plum Grove Sand Mine

May 3, 2021 Floodwaters Converging Downstream on Lake Houston

May 4, 2021 Family Trapped For Three Days As Floodwaters Ripped Through Sand Mine, Then Under Their Home

May 27, 2021 State Highway 99 Construction Pushes South, Opening Vast Areas to New Development

June 5, 2021 Eight TCEQ Investigations Reprimand Colony Ridge Construction Practices

June 9, 2021 Follow-ups: Whatever became of…?

June 10, 2021 Colony Ridge Expanding North Into More Wetlands

June 20, 2021 What’s Going On in Your Neighborhood?

July 8, 2021 To Reduce Future Flooding, We Need to Focus on BOTH Mitigation AND Root Causes

July 15, 2021 FM1485: What’s Wrong With This Picture?

July 15, 2021 Town Fighting for Survival Stonewalled By County, State Officials at Every Turn

September 3, 2021 TCEQ Again Cites Colony Ridge for Lack of Pollution Controls

November 16, 2021 Sowing the Seeds of the Next Big Flood

November 29, 2021 How to Find and Verify Flood-Related Information: Part II

December 4, 2021 Grand Parkway Extension is Getting There

December 6, 2021 “…Care Will Be Taken to Protect All Vegetation…”

December 31, 2021 Top Stories of 2021 in Review

Guess which way to colony ridge
Sediment coming down the East Fork from Colony Ridge. From “Guess which way to Colony Ridge.”


Most don’t understand the dangers of living over former wetlands.

January 20, 2022 What Does “No Adverse Impact” Really Mean in Drainage Studies?

February 16, 2022 Texas Land-Use Trends: Major Changes Coming

February 23, 2022 How Soon We Forget!

May 17, 2022 Grand Parkway Extension Opens Tomorrow

July 23, 2022 Controversial Colony Ridge Development Doubles in Size

July 29, 2022 Kingland West Clearing 1,123 Acres at FM1010 and Grand Parkway, Using Old Flood Maps


For those who always dreamed of owning an island home.

May 31, 2023, How a Controversial, Little Understood Definition Affects Flooding

August 4, 2023 Colony Ridge Buying Up Floodplain Land in Huffman

August 13, 2023 Six Years After Harvey, Bridge Still Blown Out at Colony Ridge

August 16, 2023 Colony Ridge Stormwater Detention Basins, Ditches Fail to Meet Liberty County Standards

August 29, 2023 Harvey Flood’s Sixth Anniversary Passes Virtually Unnoticed

August 30, 2023 As Wildfire Weather Sets In, Fastest Growing Area in Liberty County Fails to Meet Fire-Code Requirements

September 9, 2023 Damn the Downstream Consequences, Colony Ridge Expansion Continues Relentlessly

September 17, 2023 Colony Ridge Now 50 Percent Bigger than Manhattan

More to Come

This isn’t the end of the Colony Ridge story. I had breakfast this morning with a Kingwood resident who had given an old water heater to an acquaintance living in Colony Ridge. My friend later learned that his acquaintance piled wood under the heater and built fires to warm the water in the tank. Colony Ridge has thousands of stories like this. Come back for more.

Posted by Bob Rehak on 9/20/2023

2213 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.