News - Reduce Flooding

Going Up the Down Escalator – As HCFCD Demolishes West Fork Townhomes, Developer Builds More

Have you ever walked up a down escalator? I’m sure that’s what it must feel like to work for the Harris County Flood Control District at times. As you work to improve public safety, you sometimes fight others eroding it in the process of making a buck. Consider this comparison.

Forest Cove Buyouts V. Wanbridge New Construction

Flood Control just bought out and demolished a six-townhome complex on Timberline Drive in Forest Cove. It was the culmination of a three-year process.

Meanwhile, a short distance downstream, Wanbridge is building 14 more – even closer to the same river that destroyed the Forest Cove Townhomes. Wanbridge even designed its townhomes on the same principles used in Forest Cove (garage and storage on ground floor/living space two stories up). Let’s see how that worked out for Forest Cove property owners.

Forest Cove Complex Torn Down after Floods and Fire

Here’s what the Forest Cove complex looked like before being demolished recently.

*Part of six-unit Forest Cove Townhome flooded by Harvey and then burned on July 4th, 2019*. *Photo taken July 11, 2020.*

*Here’s what that site looks like today, 1100 days after Harvey FIRST destroyed the complex.*

Finally, a vacant lot that can return to nature!

Six Down, But Fourteen Up

Meanwhile Wanbridge is building six new units in Kings Harbor even closer to the river. That is in addition to three units just completed in the upper left, and five just completed in the lower left (some of which are out of frame).

Forest Cove Townhome Buyouts Part of a Much Larger Project

The six-unit building recently demolished in Forest Cove is part of much larger buyout project. It comprises approximately 80 homes. So far, HCFCD has demolished the following Forest Cove townhome buildings:

1030 Marina Dr.
1040 Marina Dr.
1050 Marina Dr.
1060 Marina Dr.
1102 Marina Dr.
803/805 Timberline Ct.
707 Timberline
930 Aqua Vista

However, the following buildings still have privately-owned units that HCFCD is trying to purchase ASAP:

1106 Marina Dr.
1110 Marina Dr.
1020 Marina Dr.
960 Marina Dr.
980 Aqua Vista (mostly destroyed)

HCFCD has now bought out and demolished eight out of 14 buildings (see map below).

*Map to Forest Cove Townhome buyouts. This once-thriving complex housed approximately 80 families before Harvey.*

Five Buildings Still Left Standing…Kinda

*Building sheared in half by 240,000 cubic feet per second at peak of Harvey. Residents reported feeling lucky to escape with their lives.*

*How Harvey chewed up the inside of Forest Cove Townhomes*

*Floodwaters reached well into the second stories of these units.*

*Note how the water pressure destroyed garage doors. Also note abandoned scooter.*

As I edited pictures from this morning’s photoshoot, I noticed the little girl’s scooter perched precariously on the collapsing porch. A child lived here! It was her family’s home. Their dream. And I’m sure the scooter was the girl’s cherished possession. Perhaps a birthday or Christmas present.

For whatever reason, that scooter got to me. It made me realize the futility and danger of going up the down escalator.

Public Policy Implications

From a public policy point of view, it seems like it would be safer and cheaper to buy up properties near rivers and turn them into parkland – before people build on them.

Parks generally improve the value of surrounding properties. In contrast, the inevitable eyesores created by repeat flooding cost us all. Consider:

Taxpayer subsidies for flood insurance.
Multiple payouts on insurance claims, also subsidized by taxpayers.
Eventual buyouts, paid for by taxpayers.
Demolition, paid for by taxpayers.
Eventual restoration of the green space, at taxpayer expense.
Salaries of public employees to manage this process in Washington, Austin and Houston.

Leaving these spaces green would have cost little compared to the ultimate financial and emotional costs of repeat flooding. But some people like going up that down escalator.

Posted by Bob Rehak on 9/2/2020

1100 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.

Three Years Later, Pretending Harvey Never Happened

Now that we’re past the third anniversary of Hurricane Harvey, some developers would like to pretend the storm never happened. Where money can be made, they have memory loss in abundance and common sense in short supply.

New Townhomes Feet from West Fork in Kings Harbor

I previously blogged about new townhomes under construction in Kingwood’s Kings Harbor. Technically, these townhomes may meet most of the requirements of the City of Houston. They have garages and the equivalent of indoor/outdoor living spaces on the ground floor (which are already walled off from garages). The main “living floor” starts about ten to twelve feet up. (See below and Chapter 19 of the City’s Floodplain Ordinances.)

*These new townhomes are just feet from the floodway of the West Fork in the background.*

Detention Pond Just Feet From the Water

*The barren area to the left of the six-unit complex is a detention pond. Only problem: it’s virtually in the floodway. See additional shots below.*

A retaining wall separating this property from water cuts in from the left edge of the picture (see shot below also). Flood experts advise against putting detention ponds so close to a river because they fill up quickly in a flood and fail to hold water back, which is their purpose.

Currently In 1% Annual-Chance Floodplain

The new construction currently lies within the 1% annual chance (100-year) floodplain. When the new flood maps are updated based on Atlas-14, both the floodway and floodplains will likely expand.

*Source: FEMA National Flood Hazard Layer Viewer. Aqua color equals 1% Annual Chance Flood Zone (aka 100-year flood plain). Red circle indicates location of new townhomes.*

Are 164 More Units On the Way?

The developer, Wanbridge, claims to have purchased the grassy area in the middle of the photo below as a “land bank” for 164 condos. A previous iteration of the developer’s website claimed it would be a multistory complex.

*The developer says it purchased that* *grassy area between the construction and the river* *for the purpose of building 164 condos.*

But why does Wanbridge claim to own that 2.2 acre grassy patch, when Harris County Appraisal District says it belongs to Rocky Lai’s Sunrise Kings Harbor LP? And if Wanbridge had a contract to purchase the land, why did Lai recently put it up for sale and post a sign on the property?

How Much Will Dredging Another Million Cubic Yards Reduce the West Fork Mouth Bar Area?

Earlier this month, the City of Houston announced that FEMA would pay to dredge another million cubic yards of sediment from the West Fork Mouth Bar. What does that mean in practical terms? What are the objectives of the program? How wide and deep will they go? Neither the objectives, nor a dredging plan, have yet been released.

The official plan will hopefully rely on new survey work and hydraulic modeling. A survey boat has been seen on the lake for several weeks now.

*Since January of this year, the City of Houston has been trying to reduce the above water portion of the mouth bar with mechanical dredging, a much slower process than hydraulic* *dredging. Note how shallow the water is in the foreground.*

How to Play Armchair Engineer

In the meantime, since fall football is in doubt due to COVID, here’s a simple way to keep your armchair quarterbacking skills finely honed. What would you do if you were the project engineer or manager? Play what if and experiment with different scenarios.

Download and open Google Earth Pro. It’s free.
Zoom in on the West Fork Mouth Bar.
Select the measuring tool.
Click on the polygon tab.
Select square yards for the unit measurement for the areas you will define.
Now start second guessing the project engineers. Play “what if” by defining an area that you would like to see dredged.
Readjust the points that define the area by dragging them in, out, up or down.
Watch the total square yards recalculate as you move the points.

Examples of Different Scenarios

Here are some examples to show you what I’m talking about.

4.3 Million Square Yard Area, Roughly 8 inches Deep

*Largest area. This scenario takes in everything between where the Corps stopped dredging in its Emergency West Fork Program and the FM1960 Bridge.*

The scenario above takes in the mouth of Ben’s Branch, plus all the other drainage ditches that empty Fosters Mill, Kings Point, and Atascocita north of the FM1960 Bridge.

*Here are the ditches highlighted in blue. Source: Harris County Flood Control District Flood Education Mapping Tool.*https://www.harriscountyfemt.org

The scenario above covers 4.3 million square yards. But with a budget to dredge only 1 million cubic yards, you would divide 1/4.3 = 0.23 yards of depth. That’s less than a third of a yard. It works out to about 8 inches.

3 Million Square Yard Area, 1 Foot Deep

*In the next scenario, I pulled the boundaries in so that the area equaled 3 million square yards.*

This scenario is a little more intuitive. You’re dredging 1 million cubic yards across an area of 3 million square yards. Within this bounding box, you could reduce the level of sediment roughly a foot.

2 Million Square Yard Area, 18 inches Deep

*If you reduced the area to be dredged to 2 million square yards, you could reduce the level of sediment by half a yard or 18 inches.*

1 Million Square Yards, 3 Feet Deep

*Path followed by the relict channel before Lake Houston was built.*

If you reduced the area further, to 1 million square yards, you could dredge to 3 feet. With the five feet of depth already there, you could have an eight foot channel connecting the river and the lake. Make it narrower and you could even go deeper. And perhaps, just perhaps, keep sediment from accumulating so rapidly upstream of the FM1960 bridge.

Difficult Choices Ahead

As you can see, engineers have some difficult choices ahead. They must chose between unblocking channels and streams, or dredging a channel roughly the size of the upstream west fork all the way to the 1960 bridge.

Last year, the Corps reduced the 600-acre area between the mouth bar and Atascocita Point to an average depth of 5.5 feet. So we have a good head start. But there are other considerations:

The West Fork was roughly 22 feet deep where the Corps stopped dredging just west of the mouth bar. Because of scouring, it’s at least that deep where the west fork passes under FM1960.

As a result, water coming down the west fork hits an underwater mesa that still blocks off three quarters of the conveyance.

Prominent area geologists, such as Tim Garfield and RD Kissling, theorize that that wall traps sediment and is rapidly diminishing the value of previous dredging programs. They believe that the most important objective for this phase of dredging should be to “reconnect the West Fork with the Lake.”

But Advancing Delta Now Blocks Major Streams, Channels

Meanwhile, consider this, too. In 2014, Bens Branch and the drainage ditch that empties large parts of Fosters Mill and Kings Point had a clear path to the river. Today, both are blocked by the mouth bar and an advancing delta within the lake. Compare the two images below.

*Google Earth view from 2014 shows steams could still easily connect with relict channel.*

*Today, however, an advancing delta within the lake blocks them.*

These are some of the real world trade offs that engineers and project managers must deal with every day.

So to return to the football analogy, do you send your receivers wide or deep? Do you have them hug the sidelines or cut for the goal post?

Understand that this isn’t a game, however. It’s a struggle to return a community to prosperity.

What would you do? And why?

Posted by Bob Rehak on 8/31/2020

1098 Days since Hurricane Harvey