Harris County Flood Control tomorrow will ask the Harris County Commissioners Court tomorrow to approve money for a Kingwood-wide drainage assessment. One of the reasons why is shown below: trees that have fallen into Taylor Gulley since the last time someone from Flood Control reviewed it. That underscores the need for every community association to start a flood committee. With more eyes on drainage, we might be able to keep problems such as these at a sub-acute level and help prevent flooding from clogged ditches.
Thank You, Chris Kalman
Chris Kalman of Woodstream Village sent these pictures to Flood Control and to me last Friday. They show trees that fell into Taylor Gulley during the three huge storms early last month.
This and next four photos taken on Taylor Gulley near White Oak Creek. All photos courtesy of Chris Kalman.
Blockages, such as these, can quickly turn into even bigger blockages when they catch additional trees and debris swept downstream in floods. When blockages become big enough, they can back water up into neighborhoods.
Kudos to Chris for communicating these problems (and their locations) to Harris County Flood Control. HCFCD can’t be everywhere all the time; they have 2500 miles of natural streams and man-made ditches to patrol. They need the help of residents to report problems like these so that they can respond in a timely way.
Photographs like Chris’ help Flood Control find and recognize the problems when workers visit the site. After all, in print, one downed tree sounds a lot like another. Photos also help Flood Control visualize the number of people and type of equipment to bring. In addition, Chris provided them with a map.
Commissioners Court To Consider Kingwood Drainage Assessment Project
Matt Zeve, deputy executive director of the Flood Control District is adding an evaluation of Taylor Gully and the May storm event to the scope of work for this project.
The Lake Houston area has more trees than most other parts of town. We definitely need this.
Start a Flood Committee in Your CA
Also, please urge your community association to start a “flood committee” that A) periodically checks creeks and ditches for problems and B) reports them. Often people see problems but don’t recognize them as such. Or they recognize them, but assume someone else reported them already. That’s why, in my opinion, we need to set up a system for reporting problems such as these.
An organization like KSA could coordinate the flood committees of each CA. They could then compile a master list of problems so that Flood Control could better schedule and prioritize clearing and ditch restoration efforts. It would be much more efficient for Flood Control to deal with one entity rather than thousands of individuals, many of whom might duplicate each other’s efforts. Also, as Chris discovered, sometimes it’s difficult to know whom to email. But a group that manages reporting on a regular basis could quickly learn the proper channels.
Two-foot Sections
If your neighbors, CA or trail association tries to remove such blockages, remember this. Flood Control typically cuts trees like the one above into two foot sections. Two feet is small enough to float through culverts in the next flood without getting stuck.
Posted by Bob Rehak on 6/3/2019with photos by Chris Kalman
643 Days after Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/06/erosion1.jpg?fit=1500%2C844&ssl=18441500adminadmin2019-06-03 17:15:222019-06-03 17:15:35Kingwood Drainage Assessment on Commissioners Court Agenda Tuesday and Why We Need More Systematic Reporting
SB 7 establishes special funds dedicated to flood mitigation. The bill creates dedicated Texas Infrastructure and Texas Infrastructure Resiliency Funds for flood control planning and the funding of flood planning, mitigation, and infrastructure projects.
Money from SB 7 could help fund additional flood gates for the Lake Houston spillway. They could help release water faster before and during floods such as Hurricane Harvey.
Within 90 days, a Texas Infrastructure Resiliency Fund Advisory Committee will submit recommendations to the Texas Water Development Board (TWDB) on rules it should adopt in administering the fund. TWDB has another 90 days to adopt rules governing the fund. After that, on or before the end of this year, the TWDB may begin financing projects in the state flood plan.
The bill itself takes effect immediately because it passed both the House and the Senate by more than a two-thirds majority. The Senate passed it 31-0. The House passed it 143-1 with two present but not voting. However, Article Two of SB 7 – the part dealing with the infrastructure fund – takes effect on January 1 of 2020 ONLY IF VOTERS APPROVE a constitutional amendment in November. If voters do NOT approve the constitutional amendment, Article Two has no effect.
Flood Mitigation Funding: SB 500 Implementation
SB 500 is an all-purpose special appropriations bill. It appropriates money for SB 7 and other Hurricane Harvey relief projects. For instance, it include $30 million to help dredge where the San Jacinto meets Lake Houston. SB 500 passed with greater than two-thirds majorities in both House and Senate. Therefore, it takes effect immediately.
That means $30 million should be available today to help dredge the mouth bar of the west fork.
$30 million can now used to help dredge the mouth bar.
Sand Mining Inspections and Fines: HB 907 Implementation
On its way to becoming law, the Senate strengthened HB 907. In its final form, it increased inspection frequency for all aggregate production operations (APOs) from every three years to every two.
Breach in Triple-P mine in Porter allowed process water to flow directly into Caney Creek, East Fork and Lake Houston, the source of drinking water for millions of people.
HB 907 also allows the TCEQ to conduct unannounced inspections if the TCEQ investigated a complaint about an APO operation in the previous three years.
It sets registration fees for APOs at a level that will allow the TCEQ to establish an active APO registry.
Finally, it increases penalties for failure to register an APO. It set the minimum at $5000 and the maximum at $20,000 per year with the total not to exceed more than $40,000 for any three year period.
This act takes effect on September 1, 2019. It passed in the House by 135-8 with one present and not voting. It passed in the Senate 28-3.
“Sand Trap” Bill: HB 1824 Implementation
Environmental groups and citizens, including me, fought to clarify the open-ended language in HB 1824. It allows the San Jacinto River Authority (SJRA) and Harris County Flood Control District take sand and gravel from the San Jacinto without a permit in order to restore the conveyance of the river. They can also deposit the sand and gravel on private land.
Opponents feared that it would open the door to river mining because the SJRA is essentially an economic development entity that is sensitive developers. The SJRA has also shown no desire in the past to control sand mining along the banks of the river.
When I asked legislators, miners, TACA and the SJRA how it would work, I received four different answers!
Proponents of the bill sold it as “the sand-trap bill.” The idea: to get sand mining operations to dredge the river, allow them to sell the sand, and avoid taxpayer expense. By dredging at certain locations under government supervision, proponents hoped to reduce the amount of sand coming downriver. That sand reduces the conveyance of the river and contributes to flooding.
If the bill actually works that way, great. But there’s nothing in its language that indicates how it will work or whether miners will be supervised. River mining is outlawed in many countries, including most of Europe. It has been linked to the destruction of private property in many of other countries that allow it.
Watch private sand mining activity on the river closely! This bill takes effect in three months, on September 1, 2019.
Posted by Bob Rehak on 6/3/2019
642 Days since Hurricane Harvey
The thoughts in this post represent my opinions on matters of public interest and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP statute of the great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2018/10/DifferenceMapWestFork.jpg?fit=2000%2C1129&ssl=111292000adminadmin2019-06-03 07:57:322019-06-03 08:02:47Governor Signs Flood Mitigation and Sand Mining Legislation. Now, what happens when?
The contractor also failed to repair a culvert running next to North Kingwood Forest. Engineers warned that the damaged culvert had to be replaced.
Finally the engineers may have mischaracterized the soil in modeling assumptions. They classified soil as sandy loam instead of clay. That could have skewed a key factor in runoff models by 2X to 3X.
Parts of Porter Also Flooded That Were Not in Any Recognized Flood Zone
LJA’s letter also shows that residents who flooded in Porter on the western edge of the new Woodridge development were NOT in either 100-year or 500-year flood zones. This supports the claims of Porter flood victims, such as Gretchen Dunlap-Smith. They say they never flooded before. They also claim that Rebel Contractors pushed dirt up against the western edge of the development while filling in natural drainage and wetlands. These actions likely constrained drainage on May 7th, before the contractor began installing storm sewers, drainage ditches and detention ponds in that area.
Flood Plain Maps Show What Developer’s Team Knew Before Permit Granted
Section 1.5 of LJA’s letter to Montgomery County states, “The project site is shown on FEMA Flood Insurance Rate Map (FIRM) panel 48339C0750H for Montgomery County, Texas and Incorporated Areas, revised August 18, 2014. The area just across the county boundary from the project site is shown on FIRM panel 48201C0305L for Harris County, Texas and Incorporated Areas, revised June 18, 2007.” On Page 51, the letter shows existing floodplains on the map below.
Page 51 from LJA letter to Montgomery County Engineer.The dark purple lines show the boundaries of the new development. The light purple and gray areas below the new development show the 100-year and 500-year flood plains in Elm Grove, North Kingwood Forest, Mills Branch and Woodstream Villages.Drainage on the developer’s two tracts is sloped toward Taylor Gully, Elm Grove and North Kingwood Forest in red circle.
Clearcutting of the S2 detention pond area finished last November according to Nancy Vera of Elm Grove. However, only detention pond S1 and the flow-restricting box culvert next to Vera’s house had been substantially completed by May 7. Neither N1, nor the drainage ditch connecting it with N2 were excavated on May 7th; they still have not been excavated.
At the time of the May 7th flood, only detention pond S-1 had been installed. N-2 is on land owned by Montgomery County and was at least partially excavated in 2006, but none of the devices regulating flow into or out of it had been installed on May 7th.
LJA Engineering’s models assumed all the detention ponds are in and functioning, but we know they were not at the time of the flood. Instead of installing drainage first, the contractor focused on clearcutting and grading the northern section of land which exacerbated flooding on the southern section.
Drain Pipe Should Have Been Replaced
Page 3-1 of the LJA Letter mentions, “…an existing 36-inch-diameter x 290-foot HDPE culvert in Taylor Gully at the downstream end of the project. The upstream end of the culvert is within Montgomery County and the downstream end is within Harris County. Because of its poor structural condition, this culvert needs to be replaced.”
Intake end of the pipe referenced on page 3-1 of LJA Engineer’s letter to Montgomery County.Photo taken on May 12, 2019.
Judging by the poor condition of the pipe after the May 7th flood and the lack of disturbed soil around it, I feel it’s safe to say that it wasn’t replaced at the time of the flood.
Modeling May Have Included Faulty Assumption About Soil
Major factors affecting the runoff coefficient for a watershed are land use, slope, and soil type. We know the contractor increased the runoff rate when it clearcut the forest and altered the slope of land. But I had not previously focused on how the engineers characterized the soil type, which affects water infiltration.
Sandy soils absorb more rain, generally reducing runoff.
Soils with more clay absorb less rain, generally increasing runoff.
In modeling runoff and flooding potential for Woodridge Village and downstream areas, LJA Engineers used the Army Corps’ Hydrologic Modeling System (HEC-HMS). Page 216 of the user guide for that program states that, “The sand percentage accounts for the effect of infiltration and surface runoff properties on hydrograph generation. Zero percent indicates essentially all-clay soils with characteristically low infiltration rates. Conversely, 100 percent indicates essentially all-sandy soils with characteristically high infiltration rates.”
BrighthubEngineering.com estimates infiltration rates in inches per hour for different types of soil. They show the rate for clay-based soils to average one-third to one-half the rate for sandy loam. That means…
The characterization of the soil could have skewed this component of LJA’s modeling by 2X to 3X. Certainly, that merits further investigation and verification of LJA Engineering’s results before contractors begin pouring concrete.
New Discoveries Argue for Independent Engineering Investigation
All of these observations argue for an independent investigation into the engineering of and construction practices on this site. They raise serious questions about the accuracy of LJA’s conclusions and whether their plans will protect downstream residents from future flooding.
Let’s pray that Montgomery County and the City of Houston commission a forensic investigation into the causes of this flooding. That’s the only way we’ll be able to prevent similar flooding in the future. By the time these issues work their way through the court system, contractors will have built homes and streets that could forever alter downstream flood potential. Harris County and the Federal government could be stuck with hundreds of buyouts costing tens of millions of dollars. A second opinion might save a lot of heartbreak, misery, and tax dollars. Better safe than sorry.
Posted by Bob Rehak on 6/2/2019
642 Days since Hurricane Harvey
The thoughts in this post represent my opinions on matters of public policy and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP statute of the great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/05/Flood-Impact-on-EG.jpg?fit=1500%2C998&ssl=19981500adminadmin2019-06-02 22:50:562019-06-02 22:51:06Even More Discoveries Demand Independent Investigation into Causes of Flooding Around Woodridge Village
Kingwood Drainage Assessment on Commissioners Court Agenda Tuesday and Why We Need More Systematic Reporting
Harris County Flood Control tomorrow will ask the Harris County Commissioners Court tomorrow to approve money for a Kingwood-wide drainage assessment. One of the reasons why is shown below: trees that have fallen into Taylor Gulley since the last time someone from Flood Control reviewed it. That underscores the need for every community association to start a flood committee. With more eyes on drainage, we might be able to keep problems such as these at a sub-acute level and help prevent flooding from clogged ditches.
Thank You, Chris Kalman
Chris Kalman of Woodstream Village sent these pictures to Flood Control and to me last Friday. They show trees that fell into Taylor Gulley during the three huge storms early last month.
Blockages, such as these, can quickly turn into even bigger blockages when they catch additional trees and debris swept downstream in floods. When blockages become big enough, they can back water up into neighborhoods.
Kudos to Chris for communicating these problems (and their locations) to Harris County Flood Control. HCFCD can’t be everywhere all the time; they have 2500 miles of natural streams and man-made ditches to patrol. They need the help of residents to report problems like these so that they can respond in a timely way.
Photographs like Chris’ help Flood Control find and recognize the problems when workers visit the site. After all, in print, one downed tree sounds a lot like another. Photos also help Flood Control visualize the number of people and type of equipment to bring. In addition, Chris provided them with a map.
Commissioners Court To Consider Kingwood Drainage Assessment Project
As a result of the efforts by people like Chris and Barbara Hillburn of Kingwood Lakes who has been beating the drum to improve internal drainage, HCFCD has an item on the Commissioners Court agenda for tomorrow. Item 2.a.14 on page 10 is a request for authorization to negotiate with the Lake Houston Redevelopment Authority to start HCFCD Bond Project F-14. It includes a drainage analysis of all open channels in the Kingwood area.
Matt Zeve, deputy executive director of the Flood Control District is adding an evaluation of Taylor Gully and the May storm event to the scope of work for this project.
If you are interested, any Harris County resident can sign up to speak on items on the Court agenda.
The Lake Houston area has more trees than most other parts of town. We definitely need this.
Start a Flood Committee in Your CA
Also, please urge your community association to start a “flood committee” that A) periodically checks creeks and ditches for problems and B) reports them. Often people see problems but don’t recognize them as such. Or they recognize them, but assume someone else reported them already. That’s why, in my opinion, we need to set up a system for reporting problems such as these.
An organization like KSA could coordinate the flood committees of each CA. They could then compile a master list of problems so that Flood Control could better schedule and prioritize clearing and ditch restoration efforts. It would be much more efficient for Flood Control to deal with one entity rather than thousands of individuals, many of whom might duplicate each other’s efforts. Also, as Chris discovered, sometimes it’s difficult to know whom to email. But a group that manages reporting on a regular basis could quickly learn the proper channels.
Two-foot Sections
If your neighbors, CA or trail association tries to remove such blockages, remember this. Flood Control typically cuts trees like the one above into two foot sections. Two feet is small enough to float through culverts in the next flood without getting stuck.
Posted by Bob Rehak on 6/3/2019 with photos by Chris Kalman
643 Days after Hurricane Harvey
Governor Signs Flood Mitigation and Sand Mining Legislation. Now, what happens when?
Governor Greg Abbott has signed final versions of Senate Bill (SB) #7, SB 500, House Bill (HB) #907 and HB 1824. So, what will happen when? Let’s look at the implementation of each.
Flood Mitigation: SB 7 Implementation
SB 7 establishes special funds dedicated to flood mitigation. The bill creates dedicated Texas Infrastructure and Texas Infrastructure Resiliency Funds for flood control planning and the funding of flood planning, mitigation, and infrastructure projects.
Within 90 days, a Texas Infrastructure Resiliency Fund Advisory Committee will submit recommendations to the Texas Water Development Board (TWDB) on rules it should adopt in administering the fund. TWDB has another 90 days to adopt rules governing the fund. After that, on or before the end of this year, the TWDB may begin financing projects in the state flood plan.
The bill itself takes effect immediately because it passed both the House and the Senate by more than a two-thirds majority. The Senate passed it 31-0. The House passed it 143-1 with two present but not voting. However, Article Two of SB 7 – the part dealing with the infrastructure fund – takes effect on January 1 of 2020 ONLY IF VOTERS APPROVE a constitutional amendment in November. If voters do NOT approve the constitutional amendment, Article Two has no effect.
Flood Mitigation Funding: SB 500 Implementation
SB 500 is an all-purpose special appropriations bill. It appropriates money for SB 7 and other Hurricane Harvey relief projects. For instance, it include $30 million to help dredge where the San Jacinto meets Lake Houston. SB 500 passed with greater than two-thirds majorities in both House and Senate. Therefore, it takes effect immediately.
Sand Mining Inspections and Fines: HB 907 Implementation
On its way to becoming law, the Senate strengthened HB 907. In its final form, it increased inspection frequency for all aggregate production operations (APOs) from every three years to every two.
HB 907 also allows the TCEQ to conduct unannounced inspections if the TCEQ investigated a complaint about an APO operation in the previous three years.
It sets registration fees for APOs at a level that will allow the TCEQ to establish an active APO registry.
Finally, it increases penalties for failure to register an APO. It set the minimum at $5000 and the maximum at $20,000 per year with the total not to exceed more than $40,000 for any three year period.
This act takes effect on September 1, 2019. It passed in the House by 135-8 with one present and not voting. It passed in the Senate 28-3.
“Sand Trap” Bill: HB 1824 Implementation
Environmental groups and citizens, including me, fought to clarify the open-ended language in HB 1824. It allows the San Jacinto River Authority (SJRA) and Harris County Flood Control District take sand and gravel from the San Jacinto without a permit in order to restore the conveyance of the river. They can also deposit the sand and gravel on private land.
Opponents feared that it would open the door to river mining because the SJRA is essentially an economic development entity that is sensitive developers. The SJRA has also shown no desire in the past to control sand mining along the banks of the river.
Proponents of the bill sold it as “the sand-trap bill.” The idea: to get sand mining operations to dredge the river, allow them to sell the sand, and avoid taxpayer expense. By dredging at certain locations under government supervision, proponents hoped to reduce the amount of sand coming downriver. That sand reduces the conveyance of the river and contributes to flooding.
If the bill actually works that way, great. But there’s nothing in its language that indicates how it will work or whether miners will be supervised. River mining is outlawed in many countries, including most of Europe. It has been linked to the destruction of private property in many of other countries that allow it.
Watch private sand mining activity on the river closely! This bill takes effect in three months, on September 1, 2019.
Posted by Bob Rehak on 6/3/2019
642 Days since Hurricane Harvey
The thoughts in this post represent my opinions on matters of public interest and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP statute of the great State of Texas.
Even More Discoveries Demand Independent Investigation into Causes of Flooding Around Woodridge Village
On 8/28/2018, LJA Engineers’ project manager for hydrology and hydraulics, submitted a 59-page letter to the Montgomery County Engineer’s Department. The subject: Figure Four Partner’s proposed Woodridge Village development. It shows that the developer knew of the potential for downstream flooding, yet did not develop the site in a way that might have prevented or reduced flooding.
Specifically, the developer’s team failed to construct needed detention ponds in a timely manner. They could have helped offset the effects of clearcutting the southern section of land. Instead, the contractor continued clearcutting the northern section, filled in existing drainage, and sloped land toward Elm Grove BEFORE installing needed detention ponds.
The contractor also failed to repair a culvert running next to North Kingwood Forest. Engineers warned that the damaged culvert had to be replaced.
Finally the engineers may have mischaracterized the soil in modeling assumptions. They classified soil as sandy loam instead of clay. That could have skewed a key factor in runoff models by 2X to 3X.
Parts of Porter Also Flooded That Were Not in Any Recognized Flood Zone
LJA’s letter also shows that residents who flooded in Porter on the western edge of the new Woodridge development were NOT in either 100-year or 500-year flood zones. This supports the claims of Porter flood victims, such as Gretchen Dunlap-Smith. They say they never flooded before. They also claim that Rebel Contractors pushed dirt up against the western edge of the development while filling in natural drainage and wetlands. These actions likely constrained drainage on May 7th, before the contractor began installing storm sewers, drainage ditches and detention ponds in that area.
Flood Plain Maps Show What Developer’s Team Knew Before Permit Granted
Section 1.5 of LJA’s letter to Montgomery County states, “The project site is shown on FEMA Flood Insurance Rate Map (FIRM) panel 48339C0750H for Montgomery County, Texas and Incorporated Areas, revised August 18, 2014. The area just across the county boundary from the project site is shown on FIRM panel 48201C0305L for Harris County, Texas and Incorporated Areas, revised June 18, 2007.” On Page 51, the letter shows existing floodplains on the map below.
Clearcutting of the S2 detention pond area finished last November according to Nancy Vera of Elm Grove. However, only detention pond S1 and the flow-restricting box culvert next to Vera’s house had been substantially completed by May 7. Neither N1, nor the drainage ditch connecting it with N2 were excavated on May 7th; they still have not been excavated.
LJA Engineering’s models assumed all the detention ponds are in and functioning, but we know they were not at the time of the flood. Instead of installing drainage first, the contractor focused on clearcutting and grading the northern section of land which exacerbated flooding on the southern section.
Drain Pipe Should Have Been Replaced
Page 3-1 of the LJA Letter mentions, “…an existing 36-inch-diameter x 290-foot HDPE culvert in Taylor Gully at the downstream end of the project. The upstream end of the culvert is within Montgomery County and the downstream end is within Harris County. Because of its poor structural condition, this culvert needs to be replaced.”
Judging by the poor condition of the pipe after the May 7th flood and the lack of disturbed soil around it, I feel it’s safe to say that it wasn’t replaced at the time of the flood.
Modeling May Have Included Faulty Assumption About Soil
Every time I re-read the letter to Montgomery County, new things jump out at me in light of new things I have learned. Today, I spotted another huge and potentially faulty assumption relating to runoff and flooding. The site description on page 1.1 states that the project site is “characterized by fine, sandy loam.” One of the oil industry’s leading geologists, however, characterized it as “mostly clay,” though he did say it became more sandy in natural drainage features, such as stream beds.
Major factors affecting the runoff coefficient for a watershed are land use, slope, and soil type. We know the contractor increased the runoff rate when it clearcut the forest and altered the slope of land. But I had not previously focused on how the engineers characterized the soil type, which affects water infiltration.
In modeling runoff and flooding potential for Woodridge Village and downstream areas, LJA Engineers used the Army Corps’ Hydrologic Modeling System (HEC-HMS). Page 216 of the user guide for that program states that, “The sand percentage accounts for the effect of infiltration and surface runoff properties on hydrograph generation. Zero percent indicates essentially all-clay soils with characteristically low infiltration rates. Conversely, 100 percent indicates essentially all-sandy soils with characteristically high infiltration rates.”
BrighthubEngineering.com estimates infiltration rates in inches per hour for different types of soil. They show the rate for clay-based soils to average one-third to one-half the rate for sandy loam. That means…
New Discoveries Argue for Independent Engineering Investigation
All of these observations argue for an independent investigation into the engineering of and construction practices on this site. They raise serious questions about the accuracy of LJA’s conclusions and whether their plans will protect downstream residents from future flooding.
Let’s pray that Montgomery County and the City of Houston commission a forensic investigation into the causes of this flooding. That’s the only way we’ll be able to prevent similar flooding in the future. By the time these issues work their way through the court system, contractors will have built homes and streets that could forever alter downstream flood potential. Harris County and the Federal government could be stuck with hundreds of buyouts costing tens of millions of dollars. A second opinion might save a lot of heartbreak, misery, and tax dollars. Better safe than sorry.
Posted by Bob Rehak on 6/2/2019
642 Days since Hurricane Harvey
The thoughts in this post represent my opinions on matters of public policy and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP statute of the great State of Texas.