Benefits of Flood Insurance vs. Disaster Assistance

At the 2018_FloodWarn_Training_Kingwood on May 2, Diane Cooper of FEMA pointed out several startling statistics about the Hurricane Harvey Flood and flood insurance.

Home outside the 100-year flood plain during Hurricane Harvey.

According to the City of Houston, approximately 90,000 structures OUTSIDE of the 0.2% Risk Area (500-year flood plain) were impacted. Additionally, another 30,500 structures INSIDE the 1% risk area (100-year flood plain) and 29,000 in the 0.2% risk area flooded.

However, out of approximately 150,000 total homes flooded, only 26,511 insurance claims were filed. That’s because approximately only one in six Houstonians had flood insurance.

Most people felt that if they lived outside the 1% risk area, flood insurance was an expense they could do without. Yet four in every five flooded homes were outside the 1% risk area.

Let’s examine flood insurance vs. disaster assistance as hedge against such risk.

The following information came from the National Flood Insurance Program (NFIP) portion of the FEMA website.

Flood Insurance

Flood insurance has six primary benefits:

  • You are in control. Flood insurance claims are paid even if a disaster is not declared by the President.
  • More than 20 percent of NFIP claims from from outside of mapped Special Flood Hazard Areas.
  • There is no payback requirement.
  • Flood insurance policies are continuous, and are no non-renewable or canceled for repeat losses.
  • Flood insurance reimburses you for all covered building losses up to $250,000 for residential occupancies and upon to $500,000 for businesses. Contents coverage is also available up to $100,000 for residential occupancies and up to $500,000 for businesses.
  • The average cost of a flood insurance policy is about $600 annually. The cost of a preferred risk policy is less than $450 annually, if you live in a moderate-to-low-risk area.

Disaster Assistance

Compared to flood insurance, disaster assistance has several drawbacks.

  • Most forms of Federal disaster assistance require a Presidential declaration.
  • Federal disaster assistance declarations are not awarded in all flooding incidents.
  • The most typical form of disaster assistance is a loan that must be repaid with interest.
  • The duration of a small Business Administration (SBA) disaster home loan could extend to 30 years.
  • The average Individuals and Households Program award for Presidential disaster declarations related to flooding in 2008 was less than $4,000.
  • Repayment on a $50,000 SBA disaster home load is $240 a month or $2,880 annually at 4 percent interest.

The More You Know, the Better Flood Insurance Looks

Everyone should have flood insurance. Remember, not all flooding comes from rivers and streams. During Harvey, thousands of homes flooded from overflowing streets when storm drains and sewers backed up. Floods can happen anytime, anywhere…even in deserts.

Homeowners insurance policies typically don’t cover flood damage. Disaster assistance payouts will not come close to covering all the damage that people typically suffer from a flood. And the most common type of disaster assistance is a loan that must be repaid with interest.

You can buy flood insurance through the NFIP regardless of your flood risk; it’s easy to get through any licensed broker. You can even use your credit card. Consider it seriously as we enter another hurricane season and a tropical wave is expected to slime us this weekend.

Posted by Bob Rehak on June 12, 2018

287 Days since Hurricane Harvey

Damage Map: Neighborhoods in Lake Houston Area Hardest Hit by Harvey

Structures flooded in Lake Houston area by watershed and political jurisdiction.

From this damage map, it’s clear that Kingwood suffered the most home damage in the upper Lake Houston area during Hurricane Harvey.

Harris County Food Control has worked diligently to map damage due to Harvey. The map above shows the total number of damaged homes by watershed AND political jurisdiction. The black line that divides Kingwood in two is the dividing line between East Fork and West Fork drainage.

In Harris County, there were 4,484 homes (City of Houston – Primarily Kingwood 3,652; Humble 466, Atascacita: 366) flooded by the West Fork.  Additionally, 1,290 homes (Kingwood 1,162; Huffman 128) were flooded along the East Fork.

These totals do not include additional homes flooded along each Fork that were not in Harris County, i.e., in Montgomery County. They do not include businesses. Nor do they include homes flooded further down on the lake, i.e., in Crosby or Summerwood.

These totals are lower than initially expected based on SBA and FEMA data. At a meeting of the Houston Geological Society on June 6, County Judge Ed Emmett explained that after floods many con artists file fraudulent claims. Therefore, he says, it’s common to see reductions in damage numbers after claims are investigated.

How to Read the Map

The total number of damaged structures within both the West Fork watershed and Houston appears three separate times for three different subdivisions. The total for all three is associated with each segment; do not make the mistake of adding the same number three times to get an exaggerated total for the damage.

Harris County Flood Control compiled this map for the Lake Houston Area Grass Roots Flood Prevention  Initiative. Thanks go out to Matt Zeve and his team. They are currently working on a more granular breakdown that would show damage by subdivision, for instance, Barrington, Kingwood Lakes, Kings Point, etc.

Don’t Forget Meeting Tonight: Featured Speakers from Army Corps

Don’t forget the meeting tonight at the Kingwood Community Center. Mark Micheletti will update the community on SJRA flood mitigation projects. Bill Fowler will address tax valuations. Jonathan Holley will give us a quick overview of the Harris County Flood Bond. And the featured speakers from the Army Corps will address objectives, scope, timing and details of their emergency dredging project. The meeting starts promptly at 6:30 pm and will end by 8. Please attend.

Posted 6/11/2018 by Bob Rehak

286 Days since Hurricane Harvey

 

Freese and Nichols study finds more gates on Lake Houston dam could have lowered flood during Harvey

A study by consulting firm Freese and Nichols looked at the value of adding flood gates to the Lake Houston Dam. It found that during Harvey, new gates would have lowered the level of flooding around Lake Houston by up to 1.9 feet depending on the number of gates added. Obviously, the gates by themselves won’t protect us from another Harvey, but they are an important part of a comprehensive solution that includes ongoing river dredging, ditch maintenance, debris removal, additional upstream retention, and better warning systems and more.

Modeling the Effect of More Gates on a Harvey-type Flood

Freese and Nichols conducted the gate study, which modeled flood levels only for the Hurricane-Harvey case. It did not address the impact of adding gates on smaller floods, such as those that occurred in 1994, 1998, 2001, 2015 and 2016.

Extent of modeling in Freese and Nichols study on the effects of adding floodgates to Lake Houston

Would Pre-release Help with a Storm as Big as Harvey?

Additional gates were originally proposed as a concept that could enable pre-release of water from Lake Houston as a flood mitigation strategy. The idea behind a pre-release strategy is to lower the level of a lake BEFORE a storm. The lake then has more capacity to absorb heavy rains before overflowing its banks and flooding residents, much as the City of Houston did before a small flood at the end of March.

Pre-release is currently difficult for Lake Houston because the dam consists mainly of a spillway with a fixed height – 42.5 feet above mean sea level. The Lake Houston dam does have two small gates, but they have less than one tenth the capacity of the flood gates on Lake Conroe. This makes it difficult to coordinate discharges between the two lakes.

The SJRA repeatedly cited fear of overloading the Lake Houston watershed as a reason for delaying its release from the Lake Conroe dam during Harvey. Additional gates might have reduced those concerns, encouraging the SJRA to release water earlier.

Theoretically, that could have reduced the volume of water coming down the west fork at the peak of the storm. At the peak, Lake Conroe’s release constituted one third of all the water coming down the West Fork where most of the damage occurred. It’s therefore easy to see how reducing the peak flow down the west fork could have spared hundreds of homes and businesses.

However, Freese and Nichols found that the volume of water coming into the lake during Harvey from multiple sources was too great to realize much benefit from pre-release. The amount pre-released would have quickly filled back up again  – within a few hours.

Primary Benefit Comes from Additional Discharge Capacity

This does not mean that Freese and Nichols recommended against adding gates. They found that gates would have benefitted the community, but in a different way than originally anticipated. Surprisingly, they found that the largest reduction in flood levels came simply from the additional discharge capacity that the gates provided during the peak of the flood.

Freese and Nichols states in its conclusion, “Adding additional gates to the spillway at Lake Houston would be a feasible alternative to allow for additional discharge capacity to reduce the impact of very large flood events.  … Though additional gates would provide the ability to lower the lake quickly in advance of an anticipated major flood event, the additional capacity of the gates would have far more impact on the flood level than any preliminary lowering of the lake.”

Cost/Benefit Ratio

Like many engineering studies, Freese and Nichols says that any decision to build the gates depends on whether elected officials find benefits worth the costs. However, the scope of the study did not include cost savings to home and business owners. So let’s look at that.

FEMA, the agency that would likely pay for most of the gates evaluates projects primarily on the number of people helped. They want to provide the most “benefit-per-buck” possible.

Looking at the world from FEMA’s Point of View

The City of Houston is currently in the process of developing the FEMA grant application. Mayor Sylvester Turner stated at a community meeting in Kingwood in March that he supported 10 additional gates, which he estimated would cost $47 million.

FEMA estimated in November of 2017 that 16,000 homes and 3,300 businesses in the Lake Houston area were damaged. Therefore, to reduce the impact of flooding, this project would require an expenditure of less than $2,500 per structure. Repairs to flooded structures in virtually all cases cost 10 to 100 times more than that. I know of at least one case where repairs cost $600,000. It doesn’t take many of those to equal the cost of the additional gates that the mayor proposed – $47 million.

The gates would completely eliminate flooding at the edge of the flood, and would reduce the depth of flooding inside of that.

It’s not clear at this point how many homes sit within that band where flooding could have been  eliminated. Nor is there a precise estimate of damage to those homes.

Calculating the Value of Flood Reduction

Looking at homes that would seen reduced flooding, it’s important to note that the cost of repairs correlates highly with the level of flooding. According to Bill Fowler, a real estate tax expert and Co-Chair of the Lake Houston Area Grass Roots Flood Prevention Initiative, the Harris County Appraisal District is lowering valuations on homes by the amount of flooding they experienced.

Lowering flood levels usually lowers repair costs. Lower flood levels can also lower flood insurance costs, losses to insurance companies, damage to contents, and damage to vehicles. Value can be measured many ways.

It’s also important to note when calculating value in floods smaller than Harvey, pre-release might actually become a viable strategy and greatly reduce or eliminate flooding altogether. Freese and Nichols did not evaluate additional gates from that perspective; they considered only Harvey-level flooding.

Adding floodgates to Lake Houston will be a valuable flood mitigation tool. It must be viewed as an essential PART of the solution, not THE solution. Consider its value within the context of other mitigation efforts, such as dredging, ditch maintenance, and additional upstream storage capacity.

Posted June 10 by Bob Rehak

285 Days since Hurricane Harvey

Mark Your Calendar: Meet U.S. Army Corps of Engineers Monday Night

On Monday, June 11, two representatives from the U.S. Army Corps of Engineers (USACE) will meet Kingwood residents to discuss dredging of the West Fork of the San Jacinto River. The meeting, sponsored by the Lake Houston Area Grassroots Flood Prevention Initiative, will start at 6:30 PM at the Kingwood Community Center. The emergency dredging will be one of the first flood mitigation projects related to Hurricane Harvey to be implemented in the entire Houston area.

Some Details Known, Many Yet to be Revealed

The Corps finished survey work for the West Fork Dredging Project in April. Since then, Corps members have been busy evaluating their findings, determining project specifications, soliciting bids, and planning logistics. Initial estimates indicated they would move enough sand to fill the Astrodome two and a half times.

The Corps currently expects to open bids within a week of the Kingwood meeting and quickly make a selection. Bidders have been notified that they must start the project within five days. They must also staff the project so that they can finish within six months.

Bid documents indicate dredging will extend from River Grove Park to slightly past the West Lake Houston Parkway Bridge. Residents have raised questions about additional dredging in other areas, including near Lake Houston and on the East Fork.

The Corps has identified two disposal sites for the sand. Both are existing sand pits. The first is south of the river and east of US59; the second is north of the river and west of US59. Details pertaining to mobilization, removal methods, and the extent of dredging have not yet been revealed. At the time of bidding, two removal alternatives were under consideration: mechanical and hydraulic dredging.

Meet Two Corps Representatives

Featured speakers include two representatives from the Corps who will present details of the project and field questions from residents. They are Eduardo Irigoyen, the Project Manager, and Michael Garske, a hydraulic engineer and certified floodplain manager. Both are with the Corps of Engineers’ Galveston District office.

Eduardo Irigoyen, Project Manager

Eduardo Irigoyen, U.S. Army Corps of Engineers Project Manager

Eduardo (Eddie) Irigoyen currently serves as the Emergency Dredging Project Program Manager for the West Fork of the San Jacinto River, which is funded by the Federal Emergency Management Agency (FEMA).

Irigoyen has served as a Project Manager within the Corps since May 2015. He has extensive experience within USACE ranging from programs to construction management, operations and maintenance.

His current duties include managing the planning, scope, development, design, construction, and direction of several projects along the Texas Gulf coast.

Irigoyen is a native of Brownsville, Texas. He received a Bachelor of Science in Mechanical Engineering from The University of Texas at Brownsville in 2004.

Michael Garske, Hydraulic Engineer

Michael Garske, U.S. Army Corps of Engineers Hydrologist

Michael Garske has served as a Hydraulic Engineer and Certified Floodplain Manager for USACE since September 2014.

As one of the District’s lead hydraulic modeling engineers, he’s produced inundation mapping for White Oak, Brays, and Buffalo Bayou projects, helping local officials make accurate flood mitigation decisions.

He provided critical emergency modeling data during the Tax Day, Memorial Day and Harvey floods. He has also helped design dredging templates, ecosystem mitigation banks, and water storage systems; and demonstrated their effects on flood levels.

Garske grew up in Clear Lake. In 2014, he earned a Bachelor of Science degree in Maritime Systems Engineering and an Associate of Arts degree in Maritime Administration from Texas A&M University-Galveston.

Boating Safety Measures During Project

Boaters need to be aware of dredging activities. Ultimately, the project will restore navigation on the river to pre-Harvey conditions and allow the boat launch at River Grove Park to reopen. However, until completion of the project, boaters need to avoid work sites and dredging lines for their own safety.

Agenda Including Other Speakers

The meeting will start at 6:30 p.m. at the Kingwood Community Center 4102 Rustic Woods and last until 8. It will include:

  • Mark Micheletti, one of the two new SJRA board members from Kingwood, giving updates about SJRA flood mitigation projects.
  • Bill Fowler, co-chair of the Lake Houston Area Grassroots Flood Prevention Initiative and a real-estate tax expert, will talk about revised valuations from the Harris County Appraisal District.
  • Bob Rehak, host of ReduceFlooding.com, (or a representative from Harris County Flood Control) will give a brief overview of the upcoming Harris County flood bond.
  • Irigoyen and Garske will make brief presentations and take questions from the audience. Please attend and show the Corps your appreciation for their hard work and long hours on this project.
  • A representative from FEMA will also be there to answer questions about how communities can extend projects like dredging over the long term.

The meeting is free and open to the public, so please plan to attend.

Do Not Confuse This with Flood Bond Meeting

Please note: there has been some confusion between this meeting and the Harris County Flood Bond meeting because of their dates. The County Flood bond meeting, originally scheduled for June 14, is being rescheduled for July so that County Judge Ed Emmett can attend. A new day for that meeting has not yet been determined. The meeting with the Army Corps will happen as planned on Monday evening, June 11.

Posted June 8, 2018 by Bob Rehak

Thanks to Dianne Lansden and Jacque Havelka for Planning this Meeting

283 Days since Hurricane Harvey

TACA Spells Out Industry Position on Societal and Environmental Benefits of Sand Mining

In several places on this website, I’ve talked about sand mines on the West and East Forks of the San Jacinto River. Now, the sand miners are talking about this website – in Austin – to state legislators via their trade group, TACA also known as the Texas Aggregate and Concrete Association. 

Things You Never Knew About Sand Mines

Read the TACA White Paper On The Societal and Environmental Benefits of Sand And Gravel Mining. I’m publishing it here verbatim because it is not posted publicly on the group’s own website.

Fresh sand deposits after Harvey coming out of the sand mines on the west fork of the San Jacinto adjacent to Kingwood. Note that the height of the dune is engulfing several medium sized trees.

In the document, TACA makes direct references to photos and a presentation that appear on this website. “One might look at an aerial image or fly over these operations,” they say, “and errantly [emphasis added] speculate that these operations are a potential source of sediment in a stream or river.” Later they say, “…not all sand operator stock piles were flooded in the recent storm.” They also claim, “…sand operations help to mitigate flooding.”

Sand mine in Porter next to Caney Creek covers approximately 600 acres. This stockpile covers approximately 34 acres. Note erosion patterns from Harvey in this shot taken on 9/14/17. Thirty acres of Kingwood’s East End Park, just downstream from here, was covered with sand dunes up to ten feet high during Harvey.

TACA states that one of its objectives is to promote sustainability and environmental stewardship.

One of my objectives is to promote understanding.

Sand mines on the west fork of the San Jacinto adjacent to Kingwood. Note what appears to be a breach of the dike between the mine on the left and the river about two-thirds of the way up the left side of the photo. Also notice how close the dikes are to each side of the river bank. They leave little room to accommodate flood waters.

 

Sand mines on the west fork of the San Jacinto adjacent to Kingwood.

 

Harvey’s floodwaters breached dikes surrounding the sand mines on the west fork of the San Jacinto. This let sand escape. It was carried downstream and deposited in Humble, Forest Cove, Kingwood and Atascocita.

Please Read White Paper Carefully and Closely

I urge you to read The Societal and Environmental Benefits of Sand and Gravel Mining in its entirety and draw your own conclusions. I ask only that you read it very carefully and closely, as you would a contract, because in a sense, what we are talking about IS a social contract.

Sand mines are given a license to operate next to the source of drinking water for millions of people. Are these particular sand mines operating responsibly?

In upcoming posts, I will discuss research I’ve done into best management practices for sand mining.

Posted June 7, 2018 by Bob Rehak

282 Days since Hurricane Harvey

Surprise in Final Harvey Report

Yesterday, I published on this website the 32-page Final Hurricane Harvey Flood Report from Harris County Flood Control. Today someone asked me, “What was the biggest surprise in it?”  Talk about pressure! Harris County packed lots of meat into those 32 pages! I pondered the question all morning and connected the following dots.

Five Times the Average Flow of Niagra Falls

For me, the biggest surprises were the volume of water going over the Lake Houston Dam and where it came from. At the peak of the storm, the amount of water going over the dam exceeded the volume ofNiagra Falls on an average day by 5X. The final figures actually show more water than previously thought going over the spillway: 491,800 cubic feet per second (cfs) vs. 450,000 cfs previously estimated, an increase of almost 10 percent.

More Flow From East Fork than West

When you look at where all that water came from, there was another surprise. More came from the East Fork than the West! See page 12.

In the East Fork numbers, include Peach Creek, Caney Creek and Luce Bayou; In the West Fork numbers, include Spring Creek and Cypress Creek.

One Third of West Fork Flow Came From Lake Conroe Dam Release

Roughly 240,000 cfs came down the West Fork. Seventy-nine thousand cfs came from the release at the Lake Conroe Dam, according to SJRA estimates. So ONE THIRD of the water coming down the West Fork at its peak was from the release. That’s important for the following reason.

Previously, SJRA indicated the Conroe release was approximately 15 percent of all the water going into Lake Houston. While technically true, this observation clouds the picture of what happened on the West Fork. The West Fork sustained 2.5x more damage than the East Fork and the main body of the lake COMBINED. (See Page 14). Survivor interviews suggest that much of that damage did not happen until the release from Lake Conroe!

Conclusion: Multiple Mitigation Measures Needed

That extra 79,000 cfs underscores the need to:

  • Temporarily lower the level of Lake Conroe during the peak of hurricane season
  • Enhance the carrying capacity and velocity of the West Fork through dredging
  • Add upstream retention that helps offset Lake Conroe releases
  • Add flood gates to Lake Houston.

The last item would increase the release rate of the Lake Houston dam during a major storm. The additional discharge capacity of the ten gates proposed by Mayor Turner could easily equal the 80,000 cfs discharged from Lake Conroe, eliminating a bottleneck on the river.

Of course, if we get another Harvey, many people will flood. No surprise there. But these measures should help reduce the damage, and perhaps eliminate it when we have smaller events, such as the Tax and Memorial Day Floods of 2015 and 2016.

Posted 6/5/2018 by Bob Rehak

280 Days since Hurricane Harvey

Final Harvey Report Puts Flood in Perspective

Jeff Lindner, Director Hydrologic Operations and a meteorologist with the Harris County Flood Control District, just released a fascinating compendium of statistics: the Final Harvey Report. It contains everything you need to know to impress your friends, relatives and someday, your great, great grandchildren. When they’re sitting on your knee someday, you can tell them how you survived the greatest flood since Noah.

Ultimate Guide to the Wrath of Harvey

This is the Hurricane Harvey equivalent of the Baseball Encyclopedia. It contains scorecards for every part of the county. Hollywood could start a game show with this document – Wheel of Misfortune!

The Final Harvey Report details the catastrophic devastation from Harvey flooding that occurred all across Harris County. It also puts the storm in historic context and compares it to other previous record storms. Find statistics on:

  • House flooding by watershed and jurisdiction
  • Vehicle Damage
  • Rainfall statistics (duration, totals, intensity by location, probabilities, % over previous records, peak distribution)
  • Insurance claims and coverage
  • Channel flooding, stream flow and gage statistics
  • And more…much more

Did You Know? A Sampling of Statistics from Final Harvey Report

Volume of flows entering Lake Houston from the San Jacinto Watershed

Want to know the peak inflow to Lake Houston?   491,800 cubic feet per second.

How high was the peak flow over the spillway at the Lake Houston Dam? 425,000 cfs.

What is that equivalent to? 5 times the average flow of Niagra Falls.

What was the max rainfall in one hour? 6.8 inches!

What’s the expected recurrence interval for getting 6.8 inches again in one hour? 1500 years!

How many times were 1″-rainfall-in-15-minute alarms triggered during the storm? 336 times!

Of the 154,170 estimated homes flooded across Harris County only 36% had active flood insurance policies in place the day before Harvey…64% did not have flood insurance.

Of the 154,170 homes flooded 105,340 were outside the mapped 1% (100-yr) floodplain and were not required to have flood insurance. The 154,170 is between 9-12% of the total number of structures in Harris County.

Learn more. Read the full Final HCFCD Harvey Report,

Or check out the Houston Chronicle’s coverage of the subject.

Posted by Bob Rehak on 6/4/18

Day 279 Since Hurricane Harvey

Harris County Flood Control Meeting in Kingwood Will Be Rescheduled

The meeting sponsored by Harris County Flood Control in Kingwood to explain the upcoming $2.5 billion  flood bond is being rescheduled. The rescheduling is so that County Judge Ed Emmett can attend.

The giant, new dune constricts the cross section of the East Fork by at least 50% near East End Park (background). Note how the dune reaches tree tops. The Army Corps emergency dredging project will not affect anything on the East Fork, so it is important that we put issues, such as this on the County’s flood bond agenda. 

Originally the meeting was to have been held at the Kingwood Community Center on June 14 from 6-8pm. That meeting date has been cancelled and will be reset.

June 14 Meeting Harris County Flood Control District Bond Meeting Cancelled

No new date has been set yet. As soon as the new date has been finalized, I will post it on ReduceFlooding.com.

Thanks for your patience. Few things are more important for the future of our community than this flood bond.

Posted June 4, 2018

279 Days Since Hurricane Harvey

 

 

Now is the Time to Start Thinking about Maintenance Dredging

As we prepare to dredge portions of the West Fork of the San Jacinto River for the first time, it’s also time to start planning and budgeting a regular maintenance dredging program. Let’s make sure that’s included in the August 25th $2.5 billion flood bond referendum.

Back in 2000:

…Brown & Root conducted a Regional Flood Protection Study for the Lake Houston Watershed Flood Program. At that time, Brown & Root recommended dredging as the best option to deal with sediment in the river that had accumulated from major floods in 1994 and 1998. They also recommended regular maintenance dredging every five to 10 years.

Engineers  concluded (on Page E-5), that, “…channel enlargement, primarily through sediment removal, was considered one of the more practical alternatives for achieving flood-level reduction” in this area.

Importance of Maintenance Dredging

On page 47 of its report, Brown & Root also states, “Based on the estimated sediment rate, it is expected that regular maintenance dredging at five to ten-year intervals may be necessary in maintaining the current channel conditions.”

But no dredging ever took place, even though (in conclusion on page 70) Brown & Root said, “…sedimentation may progressively aggravate future flooding as depositional areas develop in the area downstream of the Lake Houston Parkway bridge toward Lake Houston. Sediment control along the West Fork channel can be an effective means to minimizing these continued sedimentation problems.”

Ignoring Recommendations Proved Costly

Today, that report sounds prophetic. Sedimentation is exactly what happened where Brown & Root said it would happen. Here’s how the West Fork looks today where it joins Lake Houston.

During the three 500-year floods in the last three years, this West Fork sand bar at the head of Lake Houston grew exponentially. Engineers say that sediment is not being carried out into Lake Houston (background) as expected.

Major Changes Since 2000 that Have Exacerbated Flooding

Since the Brown & Root report, several major things have changed that make dredging, as well as maintenance dredging, even more important:

  • We’ve been hit by four “500-year storms” (2001, 2015, 2016, 2017). They left massive amounts of sediment in the river that have blocked drainage ditches and backed up the river itself.
  • Development has boomed between here and Lake Conroe. Upstream development brings more water to the river faster, exacerbating downstream flooding.
  • According to the Houston Chronicle, the National Oceanic and Atmospheric Administration is redefining a 100-year flood for Harris County. Instead of basing it on 12 to 14 inches of rain in a day, the new standard will be 15 to 18 inches. Said another way, many homes that weren’t in the 100-year flood plain soon will be. That’s because a 100-year flood will be based on a greater volume of rain.
  • Sand mining on the West Fork has radically increased. The orange outlines on the first map below show the locations of sand mines between Lake Houston and Conroe today. Note also the one East Fork mine.

Orange outlines show sand mines currently upstream from Lake Houston area. FM1960 Bridge over Lake Houston is in bottom right of image. Courtesy of Google Earth.

This next image from 1999 shows how many fewer sand mines existed then and how many fewer acres they occupied. Note the changes within the outlines.

At the time of the Brown & Root survey, upstream sand mines occupied approximately one fourth the acreage that they do today. 

Maintenance Dredging Could be Included in New Flood Bond

The proposed Harris County flood bond initiative currently includes language that would permit dredging of the West Fork and drainage ditches.

It is important to remember when considering this bond proposal that the US Army Corps of Engineers is only returning the river to pre-Harvey levels. That’s because they’re working with FEMA money which can only be used on Harvey-related damage.

The Harris County bond proposal, in its current, not-yet-final form states that bond funds may be used for…

…FINANCING FLOOD CONTROL PROJECTS FOR THE DISTRICT, INCLUDING … CONSTRUCTION OF IMPROVEMENTS, INCLUDING DETENTION BASINS, CHANNEL MODIFICATIONS AND OTHER WORKS SUITABLE FOR USE IN CONNECTION WITH FLOOD DAMAGE REDUCTION, AND FOR THE MAINTENANCE AND OPERATION OF SUCH IMPROVEMENTS…

Upcoming Meetings: Bond Meeting Postponed

The Harris County Flood Control District originally scheduled for 6pm on June 14th at the Kingwood Community Center has been postponed due to a conflict with Ed Emmett’s schedule. Stay tuned for updates on the new meeting date. Your attendance is important. Let’s clarify the County’s position on additional dredging and whether they support it. The language above seems sufficient to permit it, but we should clarify that.

And please also attend the meeting on June 11th, starting at 6:30pm, also at the Kingwood Community Center. It will feature the dredging project manager from the US Army Corps of Engineers.

When Dredging Will Help the Most

Dredging alone will not save many people from another storm as intense as Harvey. However, preliminary modeling suggests it could be valuable in preventing flooding from smaller and more frequent events, such as 25-, 50- and 100-year storms. Dredging and maintenance dredging are important parts of a more comprehensive solution to flooding in this area.

Posted on June 4, 2018 by Bob Rehak

279 Days since Hurricane Harvey

 

 

Case for Lowering Lake Conroe up to Two Feet During Peak of Hurricane Season

Dockline Magazine just posted three articles in its Spotlight section about lowering the level of Lake Conroe up to 2-feet during the peak of Hurricane season in late August and September.

“The Case for Lowering Lake Conroe Two Feet During Hurricane Season” represents the Lake Houston point of view. I authored it and have reprinted it below.

“Editorial on Proposal to Lower Lake Conroe Levels” sounds as though it represents the magazine’s point of view. However, it the president of the Lake Conroe Association, a group of volunteers, wrote it.

The third article, “SJRA Proposes Temporary Seasonal Lake Lowering Strategy for Lake Conroe” contains the details of the plan to lower the lake. Jace Houston, general manager of the SJRA, authored it.

Currently, the SJRA and City of Houston back the plan to lower Lake Conroe. The TCEQ  is still evaluating the proposal and expected to rule on it later this month.

The Case for Lowering Lake Conroe by up to Two Feet
During the Peak of Hurricane Season

By Bob Rehak, Lake Houston Area Resident

On April 26, in response to pleas from Lake Houston residents and a directive from the governor (to protect downstream residents from flooding), the SJRA board voted to lower the level of Lake Conroe temporarily. The lowering would amount to one foot during the rainiest months in spring and up totwo feet during the peak of hurricane season in late August and September.

I say “up to” because Lake Conroe loses on average of more than a foot and a half due to evaporation by September. The most likely reduction would be only an additional 4.8 inches. In no case would the SJRA manually lower the level of the lake beyond 199 mean feet above sea level (msl).

Nevertheless, in an open letter posted on May 11, the president of the Lake Conroe Association says his group MUST FIGHT a 2-foot reduction. He makes three arguments. Two feet would: 1) make shallow docks unusable, 2) harm tourism, and 3) reduce values of Lake Conroe homes. He says, “Families expect to enjoy their investment...’”

In the letter, he does not address how long SJRA intended the two-foot reduction to last. Nor does he discuss whether it is necessary to protect downstream residents, so allow me.

These seasonal reductions would only last until the threat to downstream residents can be reduced through other measures. In practical terms, that likely means until: 1) the U.S. Army Corps of Engineers can dredge sand buildups that exacerbate West Fork flooding, and 2) the discharge rate of Lake Houston can be synchronized with Lake Conroe’s to eliminate a bottleneck in the river system. SJRA would re-evaluate the need for temporary, seasonal reductions each year and stop them when these other mitigation measures reduce flood risk.

Downstream residents understand that lowering the lake level will make it difficult for some Lake Conroe residents and businesses to use their docks. However, a temporary lowering should not result in any permanent losses. Lake Conroe goes down almost this much naturally every year. Yet still it bounces back. The area is still renowned for its beauty and recreation. And home values have climbed steadily.

Real, Not Potential Damages

Meanwhile, the damage from flooding downstream has devastated thousands of homeowners and businesses.

According to the SBA, more than 16,000 homes and 3,300 businesses in the Lake Houston area suffered damage during Harvey. A survey last month at a meeting of the Lake Houston Area Grass Roots Flood Prevention Initiative showed that half of the residents are stillnot back in their homes – eight months after Harvey! Likewise, many businesses still have not reopened and many never will.

If you think the flood affected only people who built “too near the river,” think again. I live 1.7 miles from the river in a subdivision where 40 percent of the homes flooded. Many of my neighbors still live in hotels, with friends, or in campers as they try to restore their homes. Home damage in our little 350-acre neighborhood totaled an estimated $40 million. Most residents didn’t have flood insurance because they were nowhere near theflood plain. To finance repairs, many have taken on long-term debt, burned through retirement savings, or cashed in their children’s college funds.

Also, because of West Fork flooding during Harvey:

  • Union Pacific had to replace its bridge, disrupting rail traffic for weeks.
  • TxDoT had to replace part of the I-69 bridge, creating massive traffic delays during rush hours for months.
  • 44 percent of all Lake Houston Area Chamber businesses were adversely affected.
  • 100 percent of Humble businesses between Deerbrook Mall and the West Fork flooded on both sides of I-69.
  • 100 percent of Kingwood’s Town Center businesses closed for months.
  • Memorial-Hermann’s new Town Center facility flooded just before it opened and is still under repair.
  • Kingwood and Deerwood country clubs flooded and still have not fully reopened.
  • Lone Star College/Kingwood lost 11 of its 13 buildings for most of the school year.
  • Kingwood High School closed for 7 months and underwent repairs costing $60 million
  • 4000 students had to be bused to another high school an hour away for all that time
  • Humble ISD closed its Instructional Support Center, Welcome Center and Agricultural Barns for repairs.
  • Tax revenues from the Lake Houston area were impacted by 20-30 percent according to City of Houston estimates.
  • Humble ISD had to give out tax rebates for the last third of 2017.
  • Kingwood’s library closed for more than eight months.
  • River Grove Park had to be excavated from sand up to five feet deep.
  • Kingwood’s only community boat launch became landlocked.

Harvey knocked out the Union Pacific Railroad Bridge over the San Jacinto, disrupting rail service for weeks. Picture taken Sept. 14, 2017.

TxDoT hopes to complete I-69 bridge repairs in September, more than a year after Harvey. Picture taken May 13, 2018.

Causes for Concern

So, what caused all this devastation? Was it purely the magnitude of Harvey? Or are other factors at work?

Release Contributes to Flooding Far Outside 500-Year Flood Plain

First, the release of 79,000 cubic feet of water per second from Lake Conroe at the peakof Harvey made the flood worse. That volume represented about ONE THIRD of all the water coming down the heavily populated West Fork between Humble and Kingwood where most of the damage took place.This extra water flooded people and businesses outside the 500-year flood plain.

New Sand Deposits Back Up River and Drainage Ditches

Second, Harvey swept sand downstream, in part, from approximately 20 square miles of sand mines between I-45 and I-69. This sand blocked and backed up the river at strategic choke points. It also blocked drainage ditches leading to the river.

This massive sand bar grew 1500 feet in length and 12 feet in height during Harvey. It now blocks a drainage ditch (left center) that empties the western third of Kingwood. More than 650 homes flooded in neighborhoods that connect to this ditch.

This sandbar deposited during Harvey is an estimated 8 feet in height and stretches nearly the entire width of the West Fork.

Until dredging removes such deposits, Kingwood and Humble residents live in fear of every approaching storm.

Greater than Expected Flooding on Minor Rains

Third, even minor storms are causing much greater-than-expected flooding because of such blockages.

For example, a late-March storm this year dumped an average of five inches of rain across the watershed. It brought floodwaters two to three feet higher than a similar 5-inch rain at the beginning of last August – just before Harvey. Worse, the March flood happened AFTER Lake Houston had been lowered by 2 feet in anticipation of the storm.

Clearly, something has changed on the river. Because of massive sand deposits, such as those shown below, it won’t take another Harvey to cause significant damage.

During Harvey, thousands of homes and businesses flooded behind blockages, such as this one, where the West Fork enters Lake Houston.

At West Lake Houston Parkway (left), Harvey deposited sand in the tree tops. Sand now blocks water from flowing under the bridge and through the trees during a storm as it did before, narrowing the effective width of the river considerably.

The U.S. Army Corps of Engineers is organizing a dredging project to address such problems and expects to start in June. Until they finish and redraw the flood maps after dredging, no one really knows how many homes would flood due to Lake Conroe releases, such as those we have seen in the last three years.

Artificial Bottleneck

A fourth factor also worries Kingwood residents – the dam on Lake Houston has only two small floodgates. Combined, they have one-tenth the release rate of Lake Conroe’s. This creates a bottleneck. It greatly inhibits the ability of officials on both lakes to coordinate releases of water before storms as a flood mitigation strategy.

Houston Mayor Sylvester Turner has committed to adding ten more gates to Lake Houston and Congressman Ted Poe has asked the U.S. Army Corps of Engineers to fast-track the project.

But still, the gates must be built – just as the river must be dredged. Until we fix these problems, thousands of downstream residents will not be able to sleep soundly at night. For them, this is about survival, not recreation.

The Only Immediate Option to Reduce Flood Risk

Lowering the level of Lake Conroe is the only IMMEDIATE option that will provide a buffer against additional downstream flooding.

How much lowering is necessary? Is that extra foot really needed? If we got another storm as intense as Harvey, it would provide downstream residents only a two-hour buffer! That’s right. The storm would raise Lake Conroe that extra foot in just two-hours.

However, the two-foot reduction isn’t designed to protect against another Harvey. It’s designed to protect downstream residents against lesser floods that are abnormally high because of sand blockages like those shown above.

A two-foot reduction would let Lake Conroe absorb more water, decreasing the chances that SJRA would have to open flood gates. And if they had to open flood gates, it would delay the opening, giving downstream residents more time to evacuate.

The Lake Conroe Association will accept a one-foot reduction, but not two. That extra foot doesn’t seem like too much to ask, given all that’s riding on this decision for downstream residents as they still struggle to recover from billions of dollars in damages.

That buffer would also help protect the hundreds of Montgomery County homes that flooded around Lake Conroe and downstream from its dam.

Could another 500-year storm strike us this year? As unlikely as that seems, consider the fact that we’ve had three so-called “500-year storms” in the past three years. Something has changed out there affecting all of our assumptions. That’s why a little extra insurance would help.

Plea for Support

We ask our neighbors to the northwest for patience and support. Instead of lobbying against us, please join our fight. Help us expedite mitigation measures. With your support, our combined voices will bring change faster, so we can all return to normal life sooner.

Until then, we need to manage the river in a way that respects the lives and property of all residents on both sides of the dam, not just one.

Posted on 6/2/2018 by Bob Rehak

277 Days since Hurricane Harvey