Great news! Tuesday, Harris County Commissioners Court approved a $700,000 contract with Neel-Schaffer, Inc. for a Kingwood Area drainage study. The engineering firm will identify flooding sources in the Kingwood area and develop potential solutions.
Data shows that portions of Kingwood have potential for significant offsite flows from Montgomery County as well as ponding locations due to inadequate overland flow conveyance. Said another way, new upstream development is taxing Kingwood’s drainage infrastructure. This project will help ensure that a 100-year flood plain remains a 100-year flood plain, and doesn’t turn into a 10-, 20- or 50-year flood plain.
Area of investigation outlined in red.
Drainage Study Details Outlined in Contract
The contract for the work indicates its scope and details. Discussion of those begins in Appendix A on page 14. The goal of the study is to identify mitigation strategies that will return 12.4 miles of existing drainage ditches and streams within Kingwood to their originally designed 100-year service levels.
Harris County Flood Control District (HCFCD) entered into an interlocal agreement with TIRZ 10 (Kingwood) to perform a drainage study of five main Kingwood streams to their confluence with the West and East Forks of the San Jacinto River. The five include:
G103-33-00 Bens Branch – From Rocky Woods Drive to WFSR (Length= 3.1 miles)
G103-33-01 – From North park Drive to the confluence with Bens Branch (Length= 1.3 miles)
G103-38-00 (Kingwood Diversion Ditch)- From Harris County Boundary to WFSR (Length = 4.0 miles)
G103-80-01 (Green Tree Ditch) – From Woodland View Dr to the EFSR (Length= 1.5 miles)
G103-80-03.1B (Taylor Gully)- From Harris County Boundary to Whiteoak Creek (Length= 2.5 miles)
Flood Control Will Fund Remainder of Streams/Ditches
In addition to the interlocal agreement, Harris County Flood Control District will also study all remaining streams and ditches within the Kingwood Area. Those include another 19.9 miles:
G103-33-00 Bens Branch – From Harris County Boundary to Rocky Woods Drive (Length = 2.2 miles)
G103-33-02 – From North park Drive to the confluence with Bens Branch (Length= 0.2 miles)
G103-33-03 – From Hidden Pines Dr. to the confluence with Bens Branch (Length= 0.1 miles)
G103-33-04 – From W Lake Houston Pkway to the confluence with Bens Branch (Length= 1.2 miles)
G103-36-00 (Bear Branch)- From Woodland Hills Dr. to WFSR (Length= 2.7 miles)
G103-36-01 – From Woods Estates Dr. to the confluence with Bear Branch (Length= 0.8 miles)
G103-36-02 – From Woodland Hills Dr. to the confluence with Bear Branch (Length = 0.9 miles)
G103-36-02.1- From Kingwood Dr. to the confluence with Bear Branch (Length= 0.4 miles)\
G103-36-03- From Royal Circle Dr. to the confluence with Bear Branch (Length= 0.4 miles)
G103-38-01- From Laurel Springs Ln. to the confluence with Kingwood Diversion Ditch (Length= 1.3 miles)
G103-38-01.1- From Red Oak Terrace Ct. to the confluence with Kingwood Diversion Ditch (Length = 0.4 miles)
G103-38-02- From Harris County Line to the confluence with Kingwood Diversion Ditch (Length= 0.7 miles)
G103-39-00- From Palmetto Ln. to the WFSR (Length= 1.3 miles)
G103-41-00 (Sand Branch) – From Sycamore Creek Dr. to the WFSR (Length= 2.0 miles)
G103-41-01- From Elk Creek Dr. to the confluence with Sand Branch (Length= 0.8 miles)
G103-45-00- From Trail Tree Ln. to the WFSR (Length= 0.4 miles)
G103-46-00- From Forest Cove Dr. to the WFSR (Length = 1.0 miles)
G103-46-01- From Sweet Gum Ln. to the confluence with G103-46-00 (Length= 0.7 miles)
G103-80-01.1- From Autumn Sage Ln. to the confluence with Green Tree Ditch (Length= 0.3 miles)
G103-80-03.1A (Mills Branch) – From Same Way to Whiteoak Creek (Length = 1.5 miles)
G103-80-04 (Blackland Gully) – From Maple Knob Ct. to the EFSR (Length = 0.6 miles)
The scope of work includes several stakeholder meetings with TIRZ 10, homeowner associations, and the community at large. Their purpose: to increase public awareness and understanding of the magnitude of the watershed problems, their complexities and the cost of solutions.
Drainage Study Data Acquisition Phase
The contractor will start by collecting all available information and data including:
Construction plans
Previous drainage studies
HCFCD historical flooding data
High Water Marks
Watershed Masterplan data
FEMA Repetitive Loss properties
Flooding reports
LiDAR DEM data
Aerial maps
HCFCD watershed maps
Hydrologic and hydraulic models
City of Houston GIMS data
Any other pertinent technical data in the development of this scope of services.
Field Reconnaissance Phase
Neel-Schaffer engineers will then conduct field reconnaissance of the existing drainage systems, outfalls, and drainage patterns within the project area. That will include field measurements of 27 bridge crossings, 32 culvert crossings, 16 pedestrian bridge crossings and 6 drop structures to be incorporated in the development of hydraulic models.
During this stage, Neel-Schaffer will also measure high water marks; update floodplains; and analyze stream performance and capacity to illustrate flooding issues to the County, TIRZ and community.
Identification of Structural and Non-Structural Mitigation Alternatives
The Engineer will determine structural and non-structural improvement alternatives to bring all streams back up to the 100-year level-of-service.
Neel-Schaffer will perform this analysis using full conveyance at peak flows. Engineers will identify the major constraints that affect the available solutions for each stream.
They will then consider both structural and non-structural alternatives for mitigation.
Structural Alternatives
Structural alternatives include:
Improved drainage channels including widening, deepening, and/or lining for increased conveyance capacity.
Watershed diversions using enclosed conduits (following existing roadway alignments or other public ROW).
New regional or sub-regional detention basins and modification of existing detention basins including inlet and/or outlet structures.
Enhanced conveyance using selectective clearing and re-shaping of natural channels.
Enhanced flood storage in natural and park areas using small-scale berms and grading.
Non-Structural Alternatives
Non-Structural Alternatives include:
Property buy-outs.
Coordinated ROW dedications for future improved channels and regional detention basins.
Regional detention fees for new development.
Drainage Study Will Consider Detention Ponds
This contract includes identifying detention needs, identifying potential locations, and developing schematic layouts of the detention ponds. It also includes:
Proposed Right of Way acquisition
Preliminary Cost Estimates
A project priority and implementation plan
It is not clear at this point how long this project will take.
This post is dedicated to Barbara Hillburn, the president of the Kingwood Lakes HOA, who fought long and hard to get a project like this started. Thank you, Barbara!
Posted by Bob Rehak on 8/14/2019 with thanks to Barbara Hillburnand Precinct 4 Commissioner Jack Cagle
715 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/08/Kingwood-Drainage-Study-Area.jpg?fit=1366%2C1088&ssl=110881366adminadmin2019-08-14 15:55:322019-08-14 15:55:43Harris County Commissioners Approve $700,000 Kingwood Area Drainage Study
The Army Corps has released a new summary of its progress on dredging the mouth bar. The report indicates that Great Lakes, the contractor is now 70% complete. They have dredged 350,000 out of 500,000 cubic yards.
Great Lakes started dredging the mouth bar on June 25th, 2019, as part of a $17,085,861 extension of the original contract (FEMA mission assignment SWD-30).
Current area of operation is the blue area on the far right. Sediment removed from that area is being pumped 10 miles back upstream to Placement Area #2, a sand mine near Kingwood College, on the far left.
Between the start of mouth bar dredging and August 12, Great Lakes dredged an average of 6,363 cubic yards per day. If they can keep that pace up, they should be done by approximately Labor Day – three months ahead of schedule. That’s HALF the predicted time.
Remainder of Project Still Not Decided
What comes next? That still has not been finalized. City, County and State officials have been meeting in the background to determine that. The Army Corps still has not accepted or rejected Berry Madden’s property as a third placement area. And the $30 million appropriated by the State for mouth bar dredging won’t even become available until September 1st.
RD Kissling and Tim Garfield, two local geologists who first brought the mouth bar issue to the public’s attention, estimate that 500,000 cubic yards is about one-fourth of the total sediment that must be removed to fully restore conveyance of the West Fork.
How Shallow is It?
The Corps has not yet released (or even developed) plans for mouth bar dredging. We do know the volume they intend to remove, and the general area they intend to remove it from. However, they have refused to divulge how much of a dent their efforts will make in solving the problem.
This photo of a Kings River resident wading across the river shows how shallow it is near the orange channel marker.This resident says boats “beach” behind his property almost every day.Note: Deeper pockets may exist, especially near dredging equipment. The risk of drowning is real. Do not let children attempt this.Photo taken Sunday, August 10, 2019.The resident made it almost to the channel marker without getting his shorts wet.Shot taken with 6X telephoto lens.The lake/river within this area averages two to three feet deep. 500,000 cubic yards would lower the average level by another three feet as this calculation shows.
Problem With Stopping after 500,000 CY
The problem with stopping after the Corps finishes its 500,000 cubic yards is that the river behind this area is much deeper. Where the Corps stopped dredging just past Kings Harbor, the river is now 25-30 feet deep. And places are even deeper according to fishermen. That means water coming downriver will be forced to flow uphill in this area. That will force it to slow down and more sediment will rapidly drop out of suspension. Some experts have suggested dredging a deep channel through this area to help restore full conveyance of the river. However, the Army Corps intends to stop after 500,000 cubic yards.
“Q: What is USACE Galveston District’s plan for the rest of the mouth bar?“
“A. There is no additional work planned for the mouth bar. The current plan for the modification addressing material near the mouth bar can be found on the placemat. USACE Galveston District has no authority to conduct any additional work in the West Fork of the San Jacinto River or Lake Houston. The San Jacinto River is not an authorized federal waterway, the Corps of Engineers dredging operations are currently limited to dredging Harvey-related material. The ongoing work under the contract modification will remove the remainder of material attributable directly to Hurricane Harvey. The sedimentation from recurring annual flows are not within USACE Galveston District’s mission assignment from FEMA. Water flows on the West Fork of San Jacinto River were restored to pre-Harvey levels in December 2018.”
“Q: Who can the public contact for additional concerns with the maintenance of the San Jacinto River?“
“A. For concerns with the maintenance of the San Jacinto River, please contact Harris County Flood Control District, the San Jacinto River Authority and the City of Houston.”
Punt!
Meanwhile the City is still arguing with the Corps about how they arrived at 500,000 cubic yards. More on that later. I have obtained the Corps’ estimate through a FOIA request to the City of Houston. It raises many questions that I am still trying to sort through. More on that later.
Posted by Bob Rehak on August 14, 2019
715 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/08/MouthBar_01_01.jpg?fit=1500%2C1000&ssl=110001500adminadmin2019-08-14 13:46:172019-08-14 13:46:28Army Corps Now 70% Complete with Its Portion of Mouth Bar Dredging
With two weeks left in August and no active tropical systems in the Atlantic, Caribbean or Gulf, I started wondering how this hurricane season stacked up against the average. Through the end of July, we had two named storms in the Atlantic. We also had six in the eastern Pacific, none of which threatened land. That makes a total of eight. How does that compare to a normal year? Below is a chart from NOAA. It shows the averages for tropical storms and hurricanes by month.
167 Years of Hurricane History
The first thing I noticed when looking at this table is the clear jump between July and August. Through the end of July, the averages for both tropical storms and hurricanes are below 1. That means the chances of NOT seeing one are greater than seeing one. However, August is where things heat up (pardon the pun). Your chances of seeing one are far greater than NOT seeing one.
Through the end of July, we exceeded the averages for The Atlantic and Pacific combined. But if you look at just the Atlantic, we are about on average, as the chart below shows.
Cumulative Number of Storms Per 100 Years in The Atlantic Basin.Source: NOAA
The official hurricane season for the Atlantic Basin (the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico) is from 1 June to 30 November. As seen in the graph above, the peak of the season is from mid-August (now) to late October.
Current Outlook Clear
However, THIS August has been quiet so far. Season-to-date, we are still slightly above average, but the month of August is unusually quiet. We’re halfway through the month without any named storms in the Atlantic and NOAA expects no activity for the next five days.
Regardless, if you are the type to play the odds, so far this year Texans have to consider themselves lucky.
Lake Levels As of Mid-August
With that in mind, let’s look at what the San Jacinto River Authority (SJRA) and Coastal Water Authority are doing with Lake Conroe and Lake Houston to reduce the chance of flooding in the event of a major storm.
Both lakes are down about a foot. This creates an extra buffer against flooding by creating extra capacity within the lake.
The SJRA began lowering Lake Conroe on August 1. Normal level is 201 feet above sea level. As of this morning, Lake Conroe was at 200.03 feet and the SJRA continued to release water at a minuscule rate of 150 cubic feet per second. Evaporation is doing most of the work. The SJRA says the lake can lose up to an inch per day through evaporation in hot, dry weather, which we have had plenty of lately. You can always check the current lake level at SJRA.net.
The Coastal Water Authority is maintaining Lake Houston at 41.57 feet above sea level. Normal level is 42.38 feet. A recent lowering for dam maintenance combined with lack of recent rain and evaporation have all contributed to the current level.
The SJRA will continue releasing water at a rate that brings Lake Conroe down to 199 feet by September 1. The SJRA will maintain that level through the end of September, then allow the lake to gradually refill with rainwater until it reaches the normal level of 201 feet.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/08/peakofseason_sm.gif?fit=500%2C329&ssl=1329500adminadmin2019-08-14 11:52:152019-08-14 11:57:27How This Hurricane Season Compares to Others So Far
Harris County Commissioners Approve $700,000 Kingwood Area Drainage Study
Great news! Tuesday, Harris County Commissioners Court approved a $700,000 contract with Neel-Schaffer, Inc. for a Kingwood Area drainage study. The engineering firm will identify flooding sources in the Kingwood area and develop potential solutions.
Data shows that portions of Kingwood have potential for significant offsite flows from Montgomery County as well as ponding locations due to inadequate overland flow conveyance. Said another way, new upstream development is taxing Kingwood’s drainage infrastructure. This project will help ensure that a 100-year flood plain remains a 100-year flood plain, and doesn’t turn into a 10-, 20- or 50-year flood plain.
Drainage Study Details Outlined in Contract
The contract for the work indicates its scope and details. Discussion of those begins in Appendix A on page 14. The goal of the study is to identify mitigation strategies that will return 12.4 miles of existing drainage ditches and streams within Kingwood to their originally designed 100-year service levels.
Agreement with TIRZ 10
TIRZ 10 is a Tax Increment Reinvestment Zone established in Kingwood at the time of annexation. The TIRZ provided a replacement financing mechanism for water, sewer, drainage costs for the development of residential subdivisions once the MUDs were dissolved.
Harris County Flood Control District (HCFCD) entered into an interlocal agreement with TIRZ 10 (Kingwood) to perform a drainage study of five main Kingwood streams to their confluence with the West and East Forks of the San Jacinto River. The five include:
Flood Control Will Fund Remainder of Streams/Ditches
In addition to the interlocal agreement, Harris County Flood Control District will also study all remaining streams and ditches within the Kingwood Area. Those include another 19.9 miles:
For a map showing the location of these numbered ditches/streams, click here.
Stakeholder Meetings Part of Plan
The scope of work includes several stakeholder meetings with TIRZ 10, homeowner associations, and the community at large. Their purpose: to increase public awareness and understanding of the magnitude of the watershed problems, their complexities and the cost of solutions.
Drainage Study Data Acquisition Phase
The contractor will start by collecting all available information and data including:
Field Reconnaissance Phase
Neel-Schaffer engineers will then conduct field reconnaissance of the existing drainage systems, outfalls, and drainage patterns within the project area. That will include field measurements of 27 bridge crossings, 32 culvert crossings, 16 pedestrian bridge crossings and 6 drop structures to be incorporated in the development of hydraulic models.
During this stage, Neel-Schaffer will also measure high water marks; update floodplains; and analyze stream performance and capacity to illustrate flooding issues to the County, TIRZ and community.
Identification of Structural and Non-Structural Mitigation Alternatives
The Engineer will determine structural and non-structural improvement alternatives to bring all streams back up to the 100-year level-of-service.
Neel-Schaffer will perform this analysis using full conveyance at peak flows. Engineers will identify the major constraints that affect the available solutions for each stream.
They will then consider both structural and non-structural alternatives for mitigation.
Structural Alternatives
Structural alternatives include:
Non-Structural Alternatives
Non-Structural Alternatives include:
Drainage Study Will Consider Detention Ponds
This contract includes identifying detention needs, identifying potential locations, and developing schematic layouts of the detention ponds. It also includes:
It is not clear at this point how long this project will take.
This post is dedicated to Barbara Hillburn, the president of the Kingwood Lakes HOA, who fought long and hard to get a project like this started. Thank you, Barbara!
Posted by Bob Rehak on 8/14/2019 with thanks to Barbara Hillburn and Precinct 4 Commissioner Jack Cagle
715 Days since Hurricane Harvey
Army Corps Now 70% Complete with Its Portion of Mouth Bar Dredging
The Army Corps has released a new summary of its progress on dredging the mouth bar. The report indicates that Great Lakes, the contractor is now 70% complete. They have dredged 350,000 out of 500,000 cubic yards.
Great Lakes started dredging the mouth bar on June 25th, 2019, as part of a $17,085,861 extension of the original contract (FEMA mission assignment SWD-30).
Between the start of mouth bar dredging and August 12, Great Lakes dredged an average of 6,363 cubic yards per day. If they can keep that pace up, they should be done by approximately Labor Day – three months ahead of schedule. That’s HALF the predicted time.
Remainder of Project Still Not Decided
What comes next? That still has not been finalized. City, County and State officials have been meeting in the background to determine that. The Army Corps still has not accepted or rejected Berry Madden’s property as a third placement area. And the $30 million appropriated by the State for mouth bar dredging won’t even become available until September 1st.
Meanwhile, Callan Marine, the subcontractor from the original West Fork Emergency Dredging job has pulled its equipment back to the dock opposite Forest Cove. However, Callan has not yet started disassembling its equipment and removing it from the river. According to Houston City Councilman Dave Martin, Callan has agreed to stay temporarily while officials attempt to work out details for the next phase of dredging.
How Shallow is It?
The Corps has not yet released (or even developed) plans for mouth bar dredging. We do know the volume they intend to remove, and the general area they intend to remove it from. However, they have refused to divulge how much of a dent their efforts will make in solving the problem.
Problem With Stopping after 500,000 CY
The problem with stopping after the Corps finishes its 500,000 cubic yards is that the river behind this area is much deeper. Where the Corps stopped dredging just past Kings Harbor, the river is now 25-30 feet deep. And places are even deeper according to fishermen. That means water coming downriver will be forced to flow uphill in this area. That will force it to slow down and more sediment will rapidly drop out of suspension. Some experts have suggested dredging a deep channel through this area to help restore full conveyance of the river. However, the Army Corps intends to stop after 500,000 cubic yards.
How Army Corps Sees its Role
The Army Corps has prepared a series of FAQs that represent its position on the remainder of mouth bar dredging. Among them:
“Q: What is USACE Galveston District’s plan for the rest of the mouth bar?“
“A. There is no additional work planned for the mouth bar. The current plan for the modification addressing material near the mouth bar can be found on the placemat. USACE Galveston District has no authority to conduct any additional work in the West Fork of the San Jacinto River or Lake Houston. The San Jacinto River is not an authorized federal waterway, the Corps of Engineers dredging operations are currently limited to dredging Harvey-related material. The ongoing work under the contract modification will remove the remainder of material attributable directly to Hurricane Harvey. The sedimentation from recurring annual flows are not within USACE Galveston District’s mission assignment from FEMA. Water flows on the West Fork of San Jacinto River were restored to pre-Harvey levels in December 2018.”
“Q: Who can the public contact for additional concerns with the maintenance of the San Jacinto River?“
“A. For concerns with the maintenance of the San Jacinto River, please contact Harris County Flood Control District, the San Jacinto River Authority and the City of Houston.”
Punt!
Meanwhile the City is still arguing with the Corps about how they arrived at 500,000 cubic yards. More on that later. I have obtained the Corps’ estimate through a FOIA request to the City of Houston. It raises many questions that I am still trying to sort through. More on that later.
Posted by Bob Rehak on August 14, 2019
715 Days since Hurricane Harvey
How This Hurricane Season Compares to Others So Far
With two weeks left in August and no active tropical systems in the Atlantic, Caribbean or Gulf, I started wondering how this hurricane season stacked up against the average. Through the end of July, we had two named storms in the Atlantic. We also had six in the eastern Pacific, none of which threatened land. That makes a total of eight. How does that compare to a normal year? Below is a chart from NOAA. It shows the averages for tropical storms and hurricanes by month.
167 Years of Hurricane History
The first thing I noticed when looking at this table is the clear jump between July and August. Through the end of July, the averages for both tropical storms and hurricanes are below 1. That means the chances of NOT seeing one are greater than seeing one. However, August is where things heat up (pardon the pun). Your chances of seeing one are far greater than NOT seeing one.
Distribution of Atlantic Storms by Month
Through the end of July, we exceeded the averages for The Atlantic and Pacific combined. But if you look at just the Atlantic, we are about on average, as the chart below shows.
The official hurricane season for the Atlantic Basin (the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico) is from 1 June to 30 November. As seen in the graph above, the peak of the season is from mid-August (now) to late October.
Current Outlook Clear
However, THIS August has been quiet so far. Season-to-date, we are still slightly above average, but the month of August is unusually quiet. We’re halfway through the month without any named storms in the Atlantic and NOAA expects no activity for the next five days.
Lake Levels As of Mid-August
With that in mind, let’s look at what the San Jacinto River Authority (SJRA) and Coastal Water Authority are doing with Lake Conroe and Lake Houston to reduce the chance of flooding in the event of a major storm.
The SJRA began lowering Lake Conroe on August 1. Normal level is 201 feet above sea level. As of this morning, Lake Conroe was at 200.03 feet and the SJRA continued to release water at a minuscule rate of 150 cubic feet per second. Evaporation is doing most of the work. The SJRA says the lake can lose up to an inch per day through evaporation in hot, dry weather, which we have had plenty of lately. You can always check the current lake level at SJRA.net.
The Coastal Water Authority is maintaining Lake Houston at 41.57 feet above sea level. Normal level is 42.38 feet. A recent lowering for dam maintenance combined with lack of recent rain and evaporation have all contributed to the current level.
The SJRA will continue releasing water at a rate that brings Lake Conroe down to 199 feet by September 1. The SJRA will maintain that level through the end of September, then allow the lake to gradually refill with rainwater until it reaches the normal level of 201 feet.
Pre-emptive seasonal lowering helped avoid flooding last spring. Keep your fingers crossed!
Posted by Bob Rehak on 8/14/2019
715 Days since Hurricane Harvey