Below are several follow-ups in “capsule” form to 11 news items recently featured on ReduceFlooding.com.
Subsidence
Everyone of the people who made public comments at the Lone Star Groundwater Conservation District (LSGCD) meeting on Monday favored including a subsidence metric. Except for one. The person who stands to benefit the most from pumping more groundwater. There’s still time for you to register your opinion. Email:info@lonestargcd.org with the subject line “DFC Comments” no later than 11:59 p.m. on Jul. 19, 2021. See the post above for more information about the dangers of subsidence.
Forest Cove Townhomes
On May 26, I photographed Harris County Flood Control contractors starting to demolish one of the Forest Cove Townhome complexes on Marina Drive.
Complex at 960 Marina Drive as demolition began.Photo on June 1, 2021 of where 960 Marina Drive used to be.
A week later…down to the dirt. Three more townhome complexes to go – all on Marina Drive – and soon this whole area can revert to nature. The lesson of Forest Cove: Buyouts can take years before flood mitigation can even begin. Had developers never built here, much misery and cost could have been avoided.
But the amazing thing about erosion and entropy is that they never stop. Having completed the two sections between Woodland Hills and Kingwood Drive, HCFCD is already back working on maintenance. Local flood-fighter Chris Block alerted HCFCD to issues created by heavy rains in May. Crews are already out removing trees that fell into the natural portion of Bens Branch due to bank erosion. And HCFCD will meet local leaders Monday to review erosion in the just-completed channel south of Rocky Woods.
Bens Branch Bank Erosion and Tree Down have heavy rains in May 2021. Such trees can catch other debris being swept downstream and create “beaver dams” that back water up and flood homes.HCFCD Maintenance crews on Bens Branch on 6/06/21.Both photos courtesy of Richard Kahl.
Happy Anniversary…Tropical Storm Allison!
Twenty years ago today, Tropical Storm Allison dumped so much water on the Houston Area, flood maps were redrawn and the Tropical Storm Allison Recovery Project started. The storm hit the northeast quadrant of the the area inside Beltway 8 the hardest. It dumped 25 inches of rain in 12 hours over portions of Greens Bayou. Some neighborhoods there still have not recovered, according to Bob Robertson of Radio KAIR. He lived there at the time and recently returned.
NOAA rainfall map of Tropical Storm Allison in Harris County for 12 hours starting the evening of June 8 and the morning of June 9, 2001.The highest recorded total in the county was 28.3 inches.
Feasibility Study for Flood Control Dams on Spring Creek Tributaries
On Monday, I posted about an item on the Harris County Commissioner’s Court Agenda for Tuesday. The proposal was for a feasibility study for two flood control dams along Birch and Walnut Creeks. Both are tributaries of Spring Creek. Harris County Commissioners approved the inter-local agreement unanimously yesterday. Five municipal utility districts, the City of Humble, and the Texas Water Development board are also involved in this project. So…lots of dominoes to align. But yesterday was a step in the right direction.
Additional Floodgates for Lake Houston Dam
Mayor Pro Tem Dave Martin will hold a meeting at the Kingwood Community Center on July 8 at 6PM to discuss the status of the project. After a brief presentation, you’ll be able to meet with the engineers at small “breakout” stations to ask questions. Mark your calendar.
Woodridge Village and Taylor Gully
Harris County Flood Control District is reportedly looking at these two areas as one problem. Engineers will study combinations of a) adding floodwater detention capacity to Woodridge Village and b) additional widening or deepening Taylor Gully. Improvements in one area might be able to offset costs in another. They will look at the area from Porter all the way down to Caney Creek. Drainage from the rapidly growing White Oak Creek watershed affects part of the area, too. No date yet on recommendations.
HB2525: Dredging District
As predicted, HB2525, the bill that would have created a dredging and maintenance district for the Lake Houston Area has officially died. It passed the House. But died in the Senate’s Local Government Committee, as did the companion bill – SB 1892. File this one under “better luck next time.” The problem now is how to keep up dredging when sand mines and developments like Colony Ridge seem to send ever increasing amounts of sediment downstream.
Month after month, the confluence of the San Jacinto West Fork with Spring and Cypress Creeks looks like this. Guess which way the sand mines are.
Best Management Practices for Sand Mining
Last November, the TCEQ held a public hearing on best management practices for sand mining in the San Jacinto Watershed. Bill McCabe of the Lake Houston Area Flood Prevention Initiative and the Bayou Land Conservancy have spearheaded this issue for the area. Today, the TCEQ is holding a hearing on the rule-making. They will publish results in the Texas Register on June 25. From June 25 to July 27, TCEQ will accept public comments on the new rules. In addition, the TCEQ may also hold another public hearing on July 22.
Shortfall in Partner Contributions for Flood-Bond Projects
About $872 million in the 2018 flood bond was allocated as seed money to hopefully attract roughly $2.4 billion in partnership funds from other government agencies such as HUD, FEMA, City of Houston, and the Texas Water Development Board.
However, the Texas General Land Office (GLO) recently announced grant winners for $1.1 billion of HUD funds. Harris County Flood Control received none of that. As a result, Harris County Commissioners, HCFCD, and Harris County Budget Management have scrambled, trying to identify alternative funding sources.
The good news:
They have located alternative sources for most all of the $750 million initially projected shortfall.
No flood-bond projects have been cancelled because of funding.
We’re only three years into a ten year bond fund. So there’s still plenty of time to work things out.
Patterns of Actual Flood-Mitigation Spending in Harris County
Many special interests have alleged bias in flood-mitigation spending that just don’t seem to fit what I see on the ground. So, for the past six months, I have made multiple FOIA requests, dug through HCFCD archives, and made flights over several bayous. I’m learning the facts re: actual historical spending on capital improvement projects. Where has the money actually gone? I have published five posts so far on Halls, Greens and Brays Bayou.
Those three watersheds alone have received 43% of all capital spending since 2000 – even though they comprise just 18% of the county’s square miles and 30% of the population. That’s a far cry from the “nothing” alleged by some special-interest groups. Stay tuned for more posts on this subject. Rhetoric just doesn’t fit reality.
Posted by Bob Rehak on 6/9/2021
1370 Days after Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2021/05/20210526-RJR_7588.jpg?fit=1200%2C800&ssl=18001200adminadmin2021-06-09 12:22:502021-07-16 14:25:04Follow-ups: Whatever became of…?
Houston Mayor Pro Tem Dave Martin announced a meeting Thursday, July 8, 2021, at the Kingwood Community Center (4102 Rustic Woods) to provide updates on adding more floodgates to Lake Houston. The program to discuss the Lake Houston Dam Spillway Improvement Project will start at 6:00 p.m. The event will conclude at 7:45 p.m.
Floodgate enhancement was one of the three essential elements of the flood reduction strategy after Harvey. The other two were dredging and additional upstream detention.
At the CWA March meeting, directors also approved $4.4 million to begin Phase II of the project. Phase II calls for Black & Veatch to proceed to final engineering of the floodgates and a coffer dam to protect the work area during construction.
Lake Houston Spillway current conditionsPreliminary engineering called for crest gates to be added to the first 1000 feet of this spillway.
Additional Protection for 5,000 Structures, 35,000 Residents
The spillway improvement project will increase outflow capacity of the Lake Houston Dam, bringing it closer to that of the Lake Conroe Dam. Faster releases from Lake Houston floodgates in advance of storms will prevent or reduce upstream flooding, protecting about 35,000 residents and 5,000 structures.
This project is part of the Federal Emergency Management Agency’s (FEMA) Hazard Mitigation Grant Program. A FEMA grant provides $4.3 million for the initial phase and positions the city to receive $42.7 million for construction.
Mayor Pro Tem Dave Martin, Houston Public Works, and Coastal Water Authority have been working together under the direction of Chief Recovery Officer Stephen Costello to plan this public forum to discuss the progress of the floodgates.
Format of Meeting
Black & Veatch, the project engineers, will make a brief presentation followed by a short Q&A session and breakout sessions. The breakout session will let the community engage directly with project management staff and engineers in small groups to ask more detailed questions.
For more information, please contact the District E office at (832) 393-3008 or districte@houstontx.gov.
Posted by Bob Rehak on 6/8/2021 based on information from Dave Martin
1379 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/02/LakeHoustonDam-e1775832315715.jpg?fit=1100%2C593&ssl=15931100adminadmin2021-06-08 12:55:092021-06-08 13:04:28Save the Date: Floodgate Meeting on July 8, 6 PM at Kingwood Community Center
The conceptual feasibility study includes the design of two dams with three alternatives for each. One potential site will be along Birch Creek and another along Walnut Creek.
Spring Creek forms the Harris/Montgomery County Line for most of its length. It also bridges precincts 3 and 4 in Harris County.
Dry Dams with Fixed Height Spillways and Low-Flow Culverts
The San Jacinto River Basin Master Drainage Plan originally identified both sites. And both would feature “dry dams.” That means, they would contain no permanent water. Specs call for building the dams high enough to hold back a hundred year flood.
Each would contain a permanent fixed-height spillway. Water would flow over the spillway when it reaches 100-year level as defined in Atlas 14. The dams would also contain low-flow culverts allowing water lower than the spillway to drain slowly after a flood, as it would from a detention pond. None of the potential designs will consider gated structures.
Initial estimates in the SJR Master Drainage Plan released last year suggest that:
A 41-foot-high, 0.7 mile long dam on Birch Creek could contain 7,731 acre-feet of water in a hundred-year storm. That’s a foot of rain falling over a 12-square-mile area.
Likewise, a 46-foot-high, 1.2 mile long dam on Walnut Creek could contain 12,159 acre-feet. That’s a foot of rain falling over a 19-square-mile area.
Identifying ways to minimize or avoid environmental impacts
Soil surveys with borings up to 75 feet deep
Spillway design
Conceptual recommendations for dam design at each site
Estimating probable construction costs
Estimating land needs and costs
Identification of potential utility issues, such as pipeline crossings
Plans for raising or relocating roads, cemeteries and utilities outside the Atlas-14, 100-year floodplain
Estimating total project costs, financing costs, annual operations and maintenance costs
Developing a benefit/cost ratio based on reductions in flood damages over a 50-year period.
SJRA would lead the Spring Creek feasibility study. The local partners are seeking up to $1 million in matching funds from the Texas Water Development Board’s Flood Infrastructure Fund.
One Part of an Upstream Detention Solution
The big question is: How much benefit would people downstream in the Lake Houston Area get from Spring Creek dams? The answer is “some, but not as much as you might think.” That’s because, as you move farther downstream, the dam blocks a smaller percentage of the watershed. Think about it. Right below the dam, everything less than a 100-year storm would be intercepted. But by the time you get down to US59, you’re also getting water from Cypress Creek, Lake Creek, the West Fork and dozens of smaller streams and ditches.
So while the Spring Creek Dams could be part of a solution to offset future releases from the Lake Conroe Dam, it’s not the total solution for the Lake Houston Area. Regardless, it still would help many homes and businesses upstream along Spring Creek. Exactly how many? We’ll have to wait to see until we get the study results.
For the full text of the proposed interlocal agreement that Commissioners will vote on Tuesday, click here.
Cost of the study to local partners will depend on the match supplied by TWDB, which has not yet been finalized.
Posted by Bob Rehak on 6/7/2021 based on draft of a proposed Interlocal Agreement and the SJR Master Drainage Plan
1378 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2021/06/20210607-Screen-Shot-2021-06-07-at-1.39.44-PM.jpg?fit=1200%2C693&ssl=16931200adminadmin2021-06-07 17:32:092021-06-07 17:38:10Harris County Commissioners Vote Tuesday on Feasibility Study of 2 Dams on Spring Creek Tributaries
Follow-ups: Whatever became of…?
Below are several follow-ups in “capsule” form to 11 news items recently featured on ReduceFlooding.com.
Subsidence
Everyone of the people who made public comments at the Lone Star Groundwater Conservation District (LSGCD) meeting on Monday favored including a subsidence metric. Except for one. The person who stands to benefit the most from pumping more groundwater. There’s still time for you to register your opinion. Email: info@lonestargcd.org with the subject line “DFC Comments” no later than 11:59 p.m. on Jul. 19, 2021. See the post above for more information about the dangers of subsidence.
Forest Cove Townhomes
On May 26, I photographed Harris County Flood Control contractors starting to demolish one of the Forest Cove Townhome complexes on Marina Drive.
A week later…down to the dirt. Three more townhome complexes to go – all on Marina Drive – and soon this whole area can revert to nature. The lesson of Forest Cove: Buyouts can take years before flood mitigation can even begin. Had developers never built here, much misery and cost could have been avoided.
Bens Branch
Harris County Flood Control District (HCFCD) has worked to restore the conveyance of Bens Branch since June, 2019, in four phases: North Park to Woodland Hills; Woodland Hills to Rocky Woods; Rocky Woods to Kingwood Drive; and Kingwood Drive to just south of West Lake Houston Parkway.
But the amazing thing about erosion and entropy is that they never stop. Having completed the two sections between Woodland Hills and Kingwood Drive, HCFCD is already back working on maintenance. Local flood-fighter Chris Block alerted HCFCD to issues created by heavy rains in May. Crews are already out removing trees that fell into the natural portion of Bens Branch due to bank erosion. And HCFCD will meet local leaders Monday to review erosion in the just-completed channel south of Rocky Woods.
Happy Anniversary…Tropical Storm Allison!
Twenty years ago today, Tropical Storm Allison dumped so much water on the Houston Area, flood maps were redrawn and the Tropical Storm Allison Recovery Project started. The storm hit the northeast quadrant of the the area inside Beltway 8 the hardest. It dumped 25 inches of rain in 12 hours over portions of Greens Bayou. Some neighborhoods there still have not recovered, according to Bob Robertson of Radio KAIR. He lived there at the time and recently returned.
Feasibility Study for Flood Control Dams on Spring Creek Tributaries
On Monday, I posted about an item on the Harris County Commissioner’s Court Agenda for Tuesday. The proposal was for a feasibility study for two flood control dams along Birch and Walnut Creeks. Both are tributaries of Spring Creek. Harris County Commissioners approved the inter-local agreement unanimously yesterday. Five municipal utility districts, the City of Humble, and the Texas Water Development board are also involved in this project. So…lots of dominoes to align. But yesterday was a step in the right direction.
Additional Floodgates for Lake Houston Dam
Mayor Pro Tem Dave Martin will hold a meeting at the Kingwood Community Center on July 8 at 6PM to discuss the status of the project. After a brief presentation, you’ll be able to meet with the engineers at small “breakout” stations to ask questions. Mark your calendar.
Woodridge Village and Taylor Gully
Harris County Flood Control District is reportedly looking at these two areas as one problem. Engineers will study combinations of a) adding floodwater detention capacity to Woodridge Village and b) additional widening or deepening Taylor Gully. Improvements in one area might be able to offset costs in another. They will look at the area from Porter all the way down to Caney Creek. Drainage from the rapidly growing White Oak Creek watershed affects part of the area, too. No date yet on recommendations.
HB2525: Dredging District
As predicted, HB2525, the bill that would have created a dredging and maintenance district for the Lake Houston Area has officially died. It passed the House. But died in the Senate’s Local Government Committee, as did the companion bill – SB 1892. File this one under “better luck next time.” The problem now is how to keep up dredging when sand mines and developments like Colony Ridge seem to send ever increasing amounts of sediment downstream.
Best Management Practices for Sand Mining
Last November, the TCEQ held a public hearing on best management practices for sand mining in the San Jacinto Watershed. Bill McCabe of the Lake Houston Area Flood Prevention Initiative and the Bayou Land Conservancy have spearheaded this issue for the area. Today, the TCEQ is holding a hearing on the rule-making. They will publish results in the Texas Register on June 25. From June 25 to July 27, TCEQ will accept public comments on the new rules. In addition, the TCEQ may also hold another public hearing on July 22.
Shortfall in Partner Contributions for Flood-Bond Projects
About $872 million in the 2018 flood bond was allocated as seed money to hopefully attract roughly $2.4 billion in partnership funds from other government agencies such as HUD, FEMA, City of Houston, and the Texas Water Development Board.
However, the Texas General Land Office (GLO) recently announced grant winners for $1.1 billion of HUD funds. Harris County Flood Control received none of that. As a result, Harris County Commissioners, HCFCD, and Harris County Budget Management have scrambled, trying to identify alternative funding sources.
The good news:
HCFCD and the Budget Management Department will discuss their plans at the next Commissioners Court Meeting on 6/29/2021.
Patterns of Actual Flood-Mitigation Spending in Harris County
Many special interests have alleged bias in flood-mitigation spending that just don’t seem to fit what I see on the ground. So, for the past six months, I have made multiple FOIA requests, dug through HCFCD archives, and made flights over several bayous. I’m learning the facts re: actual historical spending on capital improvement projects. Where has the money actually gone? I have published five posts so far on Halls, Greens and Brays Bayou.
Those three watersheds alone have received 43% of all capital spending since 2000 – even though they comprise just 18% of the county’s square miles and 30% of the population. That’s a far cry from the “nothing” alleged by some special-interest groups. Stay tuned for more posts on this subject. Rhetoric just doesn’t fit reality.
Posted by Bob Rehak on 6/9/2021
1370 Days after Hurricane Harvey
Save the Date: Floodgate Meeting on July 8, 6 PM at Kingwood Community Center
Houston Mayor Pro Tem Dave Martin announced a meeting Thursday, July 8, 2021, at the Kingwood Community Center (4102 Rustic Woods) to provide updates on adding more floodgates to Lake Houston. The program to discuss the Lake Houston Dam Spillway Improvement Project will start at 6:00 p.m. The event will conclude at 7:45 p.m.
Floodgate enhancement was one of the three essential elements of the flood reduction strategy after Harvey. The other two were dredging and additional upstream detention.
Moving into Final Engineering
In its March 10th board meeting, the Coastal Water Authority (CWA) accepted the recommendation of a preliminary engineering report to add one thousand feet of crest gates to the uncontrolled spillway portion the Lake Houston Dam. The additional release capacity would let operators shed water faster before, during or after major storms to reduce the risk of flooding.
At the CWA March meeting, directors also approved $4.4 million to begin Phase II of the project. Phase II calls for Black & Veatch to proceed to final engineering of the floodgates and a coffer dam to protect the work area during construction.
Additional Protection for 5,000 Structures, 35,000 Residents
The spillway improvement project will increase outflow capacity of the Lake Houston Dam, bringing it closer to that of the Lake Conroe Dam. Faster releases from Lake Houston floodgates in advance of storms will prevent or reduce upstream flooding, protecting about 35,000 residents and 5,000 structures.
This project is part of the Federal Emergency Management Agency’s (FEMA) Hazard Mitigation Grant Program. A FEMA grant provides $4.3 million for the initial phase and positions the city to receive $42.7 million for construction.
Mayor Pro Tem Dave Martin, Houston Public Works, and Coastal Water Authority have been working together under the direction of Chief Recovery Officer Stephen Costello to plan this public forum to discuss the progress of the floodgates.
Format of Meeting
Black & Veatch, the project engineers, will make a brief presentation followed by a short Q&A session and breakout sessions. The breakout session will let the community engage directly with project management staff and engineers in small groups to ask more detailed questions.
For more information, please contact the District E office at (832) 393-3008 or districte@houstontx.gov.
Posted by Bob Rehak on 6/8/2021 based on information from Dave Martin
1379 Days since Hurricane Harvey
Harris County Commissioners Vote Tuesday on Feasibility Study of 2 Dams on Spring Creek Tributaries
Harris County Commissioners will vote tomorrow, 6/8/2021, on whether to enter into an interlocal agreement (ILA) for a feasibility study of two dams on Spring Creek tributaries. The ILA is with the San Jacinto River Authority (SJRA), the City of Humble, five Utilities Districts and the Texas Water Development Board.
The conceptual feasibility study includes the design of two dams with three alternatives for each. One potential site will be along Birch Creek and another along Walnut Creek.
Dry Dams with Fixed Height Spillways and Low-Flow Culverts
The San Jacinto River Basin Master Drainage Plan originally identified both sites. And both would feature “dry dams.” That means, they would contain no permanent water. Specs call for building the dams high enough to hold back a hundred year flood.
Each would contain a permanent fixed-height spillway. Water would flow over the spillway when it reaches 100-year level as defined in Atlas 14. The dams would also contain low-flow culverts allowing water lower than the spillway to drain slowly after a flood, as it would from a detention pond. None of the potential designs will consider gated structures.
Initial estimates in the SJR Master Drainage Plan released last year suggest that:
Components of Study
The feasibility study will include:
SJRA would lead the Spring Creek feasibility study. The local partners are seeking up to $1 million in matching funds from the Texas Water Development Board’s Flood Infrastructure Fund.
One Part of an Upstream Detention Solution
The big question is: How much benefit would people downstream in the Lake Houston Area get from Spring Creek dams? The answer is “some, but not as much as you might think.” That’s because, as you move farther downstream, the dam blocks a smaller percentage of the watershed. Think about it. Right below the dam, everything less than a 100-year storm would be intercepted. But by the time you get down to US59, you’re also getting water from Cypress Creek, Lake Creek, the West Fork and dozens of smaller streams and ditches.
So while the Spring Creek Dams could be part of a solution to offset future releases from the Lake Conroe Dam, it’s not the total solution for the Lake Houston Area. Regardless, it still would help many homes and businesses upstream along Spring Creek. Exactly how many? We’ll have to wait to see until we get the study results.
For more information about the Walnut and Birch Creek locations, see pages 39-61 in the San Jacinto River Basin Master Drainage Plan, Appendix G.
For the full text of the proposed interlocal agreement that Commissioners will vote on Tuesday, click here.
Cost of the study to local partners will depend on the match supplied by TWDB, which has not yet been finalized.
Posted by Bob Rehak on 6/7/2021 based on draft of a proposed Interlocal Agreement and the SJR Master Drainage Plan
1378 Days since Hurricane Harvey