Tag Archive for: Rocky Woods

Mobilization Begins for Next Phase of Ben’s Branch Restoration

Last week, Harris County Flood Control District (HCFCD) began mobilizing for the restoration of the Ben’s Branch drainage ditch between Kingwood Drive and Rocky Woods. The work will involve removing accumulated sediment that has diminished the conveyance capacity of the ditch.

Engineers measure conveyance in terms of “level of service.” A 100-year level of service means that a ditch will convey a 100-year rain without overflowing. The Kingwood Drainage Analysis performed last year by HCFCD revealed that sediment had reduced the conveyance of Ben’s Branch to a 2-year level of service in places. This project will restore the ditch to its original contours.

Looking north toward Rocky Woods. Most of the land between the two roads on either side of the ditch will be removed. Photo taken January 31, 2021.
Looking WSW toward intersection of Kingwood Drive and West Lake Houston Parkway. Trucks will exit Ben’s Branch by the cell tower behind the old H-E-B. Note the orange walls of the new H-E-B in the upper left. Also note the new CVS still under construction in the upper right (yellow walls). Photo taken Jan. 3, 2021.
How trucks will exist the project. Looking northwest across two temporary bridges where the two parts of Ben’s Branch come together. Work will focus on the main part on the left. Photo taken Jan. 31, 2021.
Temporary crossing for trucks coming down the west side of Ben’s Branch toward the exit on the east side by by old H-E-B. Photo taken January 31, 2021.

Importance of Project

Along Ben’s Branch, as a result of flooding during Harvey:

  • Kingwood High School immediately to the west of this project flooded badly. The building suffered $67 million in damages. The school lost another $10 million in contents. Four thousand students had to be bused to another school for seven months.
  • Homes along both sides of the ditch flooded.
  • All four shopping centers in Kingwood’s Town Center flooded. Many businesses still have not returned.
  • Thirteen people died, included twelve seniors at Kingwood Village Estates. Six died from injuries sustained during evacuation and six from stress-related illnesses after returning and finding their homes destroyed.
Looking south from northern end of project. Kingwood High School in upper right.

History of Previous Ben’s Branch Projects since Harvey

Previously, HCFCD cleaned out the portion of Ben’s Branch from the YMCA on West Lake Houston Parkway north to Kingwood Drive. This is an extension of that project. HCFCD also cleaned out the portion from Northpark Drive to Kids in Action on Woodland Hills Drive. Flood Control could not obtain permission to excavate anything in the natural portion of Ben’s Branch between St. Martha’s Catholic School and Rocky Woods. However, HCFCD did clean out underbrush to let water flow faster through that area.

Scope of Current Work

For the current work between Kingwood Drive and Rocky Woods, HCFCD will start at the downstream end and work its way north. The work should take about five months. It involves removing more than 22,000 cubic yards of sediment, restoring the original banks of the ditch, and replacing a number of outfall pipes that have become blocked or damaged over time.

Once the work begins in earnest, HCFCD contractors will enter the northern side of the project at the end of Cedar Knolls and move south toward Kingwood Drive. There, they will exit the project behind the old H-E-B store. Crews will work around Kingwood High School start/stop times to reduce traffic snarls.

HCFCD considers this a maintenance project, not a capital-improvement project.

Related Projects in Kingwood

The Kingwood Drainage Analysis identified two much-needed capital improvement projects in Kingwood:

  • Expansion of the Diversion Ditch that runs from the new St. Martha Church down to Deer Ridge and River Grove Parks where it eventually enters the West Fork. The purpose of the Diversion Ditch project: to further reduce the flow of water into Ben’s Branch.
  • A project to reduce flooding along Taylor Gully. Two options have been discussed:
    • Widening and deepening Taylor Gully itself
    • Establishing a regional detention pond on the land owned by Perry Homes’ subsidiary Figure Four Partners.

HCFCD has not announced a timetable yet for either of those projects. Any work on Taylor Gully would depend on whether Harris County and the City are able to negotiate the purchase of Woodridge Village from Perry. Woodridge Village is the aborted development that twice flooded Elm Grove and North Kingwood Forest Villages in 2019.

Posted by Bob Rehak on 2/3/2021

1253 Days since Hurricane Harvey

HCFCD Will Begin More Work on Ben’s Branch Starting January 19

Harris County Flood Control District (HCFCD) will begin repairing the next section of Ben’s Branch on January 19. The repairs will take place in the channel between Kingwood Drive and the natural portion of Ben’s Branch at the end of Rocky Woods Drive.

Project limits for next phase of Ben’s Branch clean out. Kingwood High School in lower center of frame.

Project Purpose

Jose Predraza of Stuart Consulting is coordinating the project. He said, “The purpose of this project is to restore the conveyance of Ben’s Branch. It has been reduced over the years due to erosion and sedimentation. The project will include implementing erosion repairs, repairing side slope failures, repairing or replacing outfalls, rectifying flow lines, and removing excess sediment.”

Contractors will remove approximately 22,000 cubic yards of sediment deposited by floods over the years.

Continual cycles of deposition and erosion have clogged, deformed and narrowed the creek.

The Kingwood Area Drainage Analysis showed that Ben’s Branch had been reduced to a 2-year level of service in places. That means, it will flood in a 2-year rain.

The analysis did not specify whether this was one of those places, but outside the natural portion of the stream, this is currently the most constricted part. Other parts of the channel have already been restored, i.e., from Woodland Hills Drive to Northpark Drive and south of Kingwood Drive to the YMCA.

Red lines represent approximate outlines of original high banks near Rocky Woods. Area between red lines has filled with sediment and then the creek has eroded down through it again repeatedly. Photo 1/8/2021.

“Erosion repairs include the placement of fill material, placement of 3”x5” granular fill, and the placement of grade #1 riprap,” continued Pedraza. “Channel cross sections will be reconstructed with a maximum 5:1 (H:V) slope where necessary. This project will be conducted wholly within the existing channel right-of-way.”

Schedule

Pedraza estimates construction will last 145 days – not quite five months. If weather cooperates, contractors should complete the work in early June.

The project originally was scheduled to start in October 2020. But several delays occurred.

  • Initially, rain delayed completion of the survey.
  • Then, geotechnical investigations led to additional design time.
  • Finally, getting approval to cross CenterPoint’s power-line easement took additional time.

Access Routes

Trucks do not have enough room to turn around within the work area, so one-way traffic will be the rule. Trucks will enter the work area by coming up Woods Estates Drive to Cedar Knolls and entering the greenbelt from there. They will then follow the Centerpoint easement to the work area. Finally, they will exit by going south toward Kingwood Drive, cutting across the ditch, and coming out behind the old H-E-B.

Contractors will then haul the excavated dirt to nearby TCEQ-approved landfill sites outside of the .02% annual chance (500-year) flood plain.

Daily schedules are being coordinated with Kingwood High School start/stop times to reduce traffic congestion and improve safety.

Benefitting Residents, Schools and Businesses

When complete, the creek will be able to handle much more water than before without coming out of its banks…as much as it could when Friendswood originally excavated it.

This will be a vast improvement, especially for those who live near the creek in Kings Forest and Bear Branch, many of whom flooded during Harvey.

The work should reduce the flood risk for Kingwood High School also. The school first flooded in 1994. During Harvey, the building flooded to the second floor. It suffered $67 million dollars in damages and lost another $10 million in contents. The Humble ISD had to close Kingwood High for seven months and bus kids to another high school where they alternated “shifts” with the students from that high school.

Kingwood High also flooded during Imelda, but had less damage.

Finally, the work will also benefit the shopping center on the northwest corner of Kingwood Drive and West Lake Houston Parkway. Every store in the center flooded badly during Harvey. Many businesses still have not returned. The center nearly flooded again during Imelda. Water flowed through the parking lot and was inches from coming into stores.

Paths along the high banks represent the original edges of the channel. Everything between them has filled in over time, reducing conveyance. Photo 1/8/2021.

Funding

The Ben’s Branch project will be funded through the HCFCD maintenance budget and a grant from USDA Natural Resources Conservation Service (NRCS).

Posted by Bob Rehak on 1/9/2021

1229 Days since Hurricane Harvey

HCFCD to Begin Next Phase of Ben’s Branch Clean Out in October

Harris County Flood Control District (HCFCD) and its contractors met today with representatives of Kings Forest, the Bear Branch Trail Association and Kingwood Service Association to discuss the next phase of the Ben’s Branch clean out. On the south, the project lies entirely within the Creekwood Nature Area between Kingwood High School and the old H-E-B shopping center. Rocky Woods Drive forms the northern extent of the project. This will extend northward the work already completed south of Kingwood Drive.

Project extent outlined in red. Kingwood High School is at bottom center; Town Center on right; Kings Forest on left and Bear Branch at top of frame.

Maintenance Objective: Restore Conveyance

The objective: to restore conveyance of Ben’s Branch and reduce potential for flooding in Kings Forest, Bear Branch, the Kingwood High School, and Kingwood Town Center.

The ground these men are standing on is all deposited sediment that needs removal to restore conveyance. The original channel bank is the higher slope behind them. The other side has a similar problem.

Sediment has restricted the flow of the channel gradually during the last three decades. It now contributes to flooding.

Tucked into the tree line on either side of Bens Branch, you can see the maintenance roads that formed the top of the original banks.

During Harvey, many homes on both sides of the stream flooded. Many also flooded again during Imelda.

Walking along the creek today, the first thing one notices is a craggy channel with sides that seem to have slumped into the stream. Flood control surveys, however, show that is not the case. The channel filled with sediment. Then the stream eroded down again through the accumulated sediment.

Continual cycles of deposition and erosion have clogged, deformed and narrowed the creek.

Approximately 15,000 Cubic Yards of Sediment To Be Removed

Getting the channel back to its original state will require removal of approximately 15,000 cubic yards of sediment. However, engineers have not yet determined the exact number.

The scope of work will include replacement of damaged drain pipes that carry water to the ditch.

The job is still in its planning stages. Actual dirt work should begin sometime in October.

Funded with Help from USDA NRCS

A grant from the USDA Natural Resources Conservation Service (NRCS) will help HCFCD fund the project. Contractors will haul the excavated dirt to nearby TCEQ-approved landfill sites outside of the .02% annual chance (500-year) flood plain.

Looking north. The project will NOT extend into the natural portion of Ben’s Branch at the top of the frame, near Rocky Woods Drive. It will affect only the man-made portion of the channel.

Downstream, the project will stop at Kingwood Drive. Note below how the channel under the Kingwood Drive bridge is virtually twice as large as the channel in the foreground.

Looking south over Ben’s Branch toward Kingwood Drive and the portion of Ben’s Branch restored earlier this year. Note how constricted the channel in the foreground is.

When complete, this project should make the channel north of Kingwood Drive as wide as it is south of Kingwood Drive. It’s all about getting the channel back to its designed carrying capacity.

An exact timetable for the project is not yet available, but it will take several months.

Posted by Bob Rehak on 9/4/2020

1102 Days after Hurricane Harvey