On Thursday, July 8, Mayor Pro Tem Dave Martin will host a pubic meeting to discuss the status of adding more floodgates to the Lake Houston Dam. Preliminary engineering finished earlier this year. In March, the Coastal Water Authority board approved Black & Veatch to begin final engineering.
Need for More Gates
The Lake Houston Area Task Force identified more and higher capacity floodgates as a key element in the area’s flood-mitigation strategy. The current gates have one-fifteenth the capacity of those at the Lake Conroe Dam. That makes it difficult to shed water from Lake Houston before people flood if Lake Conroe opens its gates as it did during Harvey.
Lake Houston Dam During Harvey. The proposed crest gates would go in the far upper left of the spillway.
Floodgate Meeting Details
See the meeting details below.
Thursday, July 8, 2021 At the Kingwood Community Center (4102 Rustic Woods) Doors Open 5:30 PM Dredging Update Starts 5:45 PM Gate Update Starts at 6 PM
Chief Recovery Officer, Stephen Costello, will provide a very brief update on Lake Houston Dredging operations at 5:45 p.m. before the Spillway Improvement Project program begins.
The main presentation by Black & Veatch, the project engineers, will be followed by a short Q&A session. The meeting will then transition into breakout sessions. Breakout tables will let residents engage with project management staff and engineers in small groups to ask more detailed questions.
Project Benefits
The Lake Houston Dam Spillway project will increase the outflow capacity of the Lake Houston Dam. The project proposes installing new crest gates in the existing uncontrolled spillway. This will allow for a rapid decrease of water levels in Lake Houston in advance of storm events to prevent or reduce upstream flooding. Engineers estimate the recommended alternative could help about 35,000 residents and 5,000 structures. It’s important for people to understand that if they flooded from streams or channels far from the lake during Harvey, this may not help them.
Funding
A Federal Emergency Management Agency (FEMA) Hazard Mitigation Grant Program provides $4.3 million for engineering and positions the city to receive another $42.7 million for construction.
Posted by Bob Rehak on 7/6/2021 based on info provided by Dave Martin’s Office
1407 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/02/LakeHoustonDamDuringHarvey.jpg?fit=1500%2C968&ssl=19681500adminadmin2021-07-05 23:31:172021-07-06 10:16:41Reminder: Floodgate Meeting at Kingwood Community Center on Thursday, July 8
On June 29, 2021, Harris County Flood Control District (HCFCD) gave Commissioners an update on the progress of new flood maps and flood-insurance-risk ratings. The flood-map changes could become effective as early as late 2023. FEMA’s new Risk Rating 2.0 system for flood-insurance pricing will be phased in during the next few years. See details below.
MAAPnext About Half Complete
MAAPnext is Harris County’s Modeling, Assessment and Awareness Project. The purpose: to develop the next generation of flood maps and tools. It will provide a better assessment of flood risks for individual properties, and make the nature of those risks easier for property owners to understand.
One of the significant changes: the new maps will capture different types of flooding, such as street flooding. This is currently the biggest missing piece of the flood-risk rating picture, according to the MAAPnext project team.
The new maps will also come with individual property reports that estimate flood depth, water-surface elevations, annual-chance of flooding grids, and 30-year chance of flooding grids. That last will estimate your chance of flooding at least once during a 30-year mortgage. The flood map grids will also be more detailed. They will provide estimates down to the 3 ft X 3 ft level.
FEMA and Harris County expect to have:
Draft flood-risk maps and associated data available for public review by the end of this year.
Preliminary Flood Insurance Rate Maps (FIRMs) for release by next summer.
Public meetings to review and explain the FIRMs to officials and residents during the second half of next year.
The earliest likely date that the new rate maps could become effective: late 2023.
Changes to flood-insurance premiums as a result of map changes could only happen after the new maps become effective.
FEMA is updating the National Flood Insurance Program‘s (NFIP) risk rating methodology through the implementation of a new pricing methodology called Risk Rating 2.0. The methodology leverages industry best practices and cutting-edge technology to enable FEMA to deliver rates that are actuarily sound, equitable, easier to understand and better reflect a property’s flood risk.
More Risk Factors Considered
Elevations, flood-hazard zones, and rating tables will no longer be the only metrics used in calculating the flood-insurance premium for a property. For example, premiums will be distributed across all policyholders based on home values and a property’s unique flood risk. FEMA will also consider flood frequency, multiple flood types—river overflow, storm surge, coastal erosion and heavy rainfall—and distance to a water source along with property characteristics such as elevation and the cost to rebuild.
More Equitable Rates
Currently, many policyholders with lower-value homes are paying more than they should and policyholders with higher-value homes are paying less than they should.
That said, FEMA expects 87% of single-family homes to see a flood-insurance-premium increase of about $120 per year. Another 4% could see an increase of about $121 to $360 per year. Finally, 9% could see a decrease of up to $1,200 per year.
New policy holders will be subject to the new rates.
Current policy holders eligible for renewal can take advantage of premium decreases.
Starting in April 2022:
Existing policy holders who expect an increase with the new method could renew under Risk Rating 2.0, but will have an option to keep their current policies if cheaper for up to two years.
All remaining policies renewing on or after April 1, 2022, will be subject to the new rating methodology.
Contact your flood insurance agent to clarify all timing, rate and discount questions.
How Does MAAPnext Factor into Risk Rating 2.0?
Harris County Flood Control District in partnership with FEMA lead the MAAPnext effort to revise flood insurance rate maps. FEMA alone leads the Risk Rating 2.0 effort to calculate new flood insurance rates. The maps will help calculate new premiums.
Posted by Bob Rehak on July 4, 2021 based on information from HCFCD and FEMA
1405 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2021/07/NFIP-Rate-Increases-Decreases.jpg?fit=1200%2C881&ssl=18811200adminadmin2021-07-04 12:50:072021-07-04 13:21:38Progress Report on New Flood Maps and Flood-Insurance-Risk Ratings
On June 29, 2021, Harris County Commissioners approved two contracts for preliminary engineering on Taylor Gully and the Kingwood Diversion Ditch. The Taylor Gully project includes looking at Woodridge Village in Montgomery County to possibly expand detention-pond capacity there. See more below.
Taylor Gully Project
Harris County Flood Control District (HCFCD) awarded Idcus, Inc. a $180,555 preliminary engineering contract to develop up to five conceptual alternative scenarios for modifying Taylor Gully. HCFCD and Idcus will then select three scenarios for more detailed analysis. Idcus must perform the work within 300 days of the Notice to Proceed.
The alternative modeling scenarios may include:
Preferred Channel Alternative: This would look at improving the slope, width and lining of channel in conjunction with the existing detention on the Woodridge Village site. This purpose: to determine if the existing detention and proposed channel improvements suffice to mitigate flooding.
Expanded Detention: This would look at expanding the existing stormwater detention on the Woodridge Village site so that no channel improvements are necessary.
Alternative Channel/Detention: This would look at a combination of the two scenarios above. It would determine the amount of additional detention and channel improvements necessary to ensure no adverse impact all the way to Lake Houston.
Optimization Alternative: Building on the alternatives above, this effort would examine additional alternatives to produce a no-adverse-impact solution while maximizing the flood mitigation and minimizing construction costs.
Deliverables for the alternatives include:
Channel and basin layouts
Estimates of benefits for various levels of storms (100-year, etc.)
Right-of-way requirements
Cost estimates for right-of-way acquisition, engineering and construction management.
Performance metrics, i.e., estimated acreage of land inundation, number of structures in floodplain, number of structures flooded and miles of inundated roadway.
A scoring matrix to rank the alternatives.
The scope also includes, when necessary:
Hydrologic and hydraulic analysis
Surveying
Soil sampling
Environmental site assessment
Subsurface utility exploration
Landscape architecture
Finally, Idcus will hold two public engagement meetings near the beginning and end of the project and consult with community groups such as KSA.
Geographic scope includes the Woodridge Village property in MoCo plus the Taylor Gully channel in Harris County.
Kingwood Diversion Ditch
HCFCD entered into a contract with Neel-Schaffer, Inc. for $437,685 for preliminary engineering on the Kingwood Diversion Ditch. Within 300 days,Neel-Schaffer must:
Evaluate existing site conditions, previous studies, other projects that could affect this one, topography, rights-of-way, utilities, and soil surveys.
Evaluate existing bridges
Conduct and H&H analysis to assess existing and proposed conditions (from 2-year to 500-year storms).
Analyze Channel Improvements including the:
Impact of TIRZ #10’s latest design to replace the Northpark Bridge
Diversion structure at the confluence of Bens Branch and the Diversion Channel
Drop structures in lieu of a concrete lined channel to minimize high velocities due to the steep grade between Walnut Lane and Deer Ridge Estates Blvd.
Develop phased construction plans based on available funding, potential impacts and benefits.
Conduct two public engagement meetings and coordinate with community groups.
HCFCD may also require Neel-Schaffer to provide addition services when necessary, such as:
Surveys
Geotechnical investigations, i.e., bridge borings
Environmental assessment
“Jurisdictional” determination. Does this channel fall under the jurisdiction of the Army Corps? If so, channel design may need to be altered.
Determination of detention pond requirements
Exploration for subsurface utilities
Obtaining permits from the Corps
Providing Landscape Architect services
Extent of Kingwood Diversion Ditch. It runs from the new St. Martha Catholic Church north of Northpark to the fire station on Kingwood Drive. Then it runs down to Deer Ridge Park where it makes a turn and enters the West Fork at River Grove Park.
For Complete Text of Contracts…
The first half of each link below contains contract details such as compensation. The second half contains the scope of work.
Reminder: Floodgate Meeting at Kingwood Community Center on Thursday, July 8
On Thursday, July 8, Mayor Pro Tem Dave Martin will host a pubic meeting to discuss the status of adding more floodgates to the Lake Houston Dam. Preliminary engineering finished earlier this year. In March, the Coastal Water Authority board approved Black & Veatch to begin final engineering.
Need for More Gates
The Lake Houston Area Task Force identified more and higher capacity floodgates as a key element in the area’s flood-mitigation strategy. The current gates have one-fifteenth the capacity of those at the Lake Conroe Dam. That makes it difficult to shed water from Lake Houston before people flood if Lake Conroe opens its gates as it did during Harvey.
During Harvey, Conroe released 79,000 cubic feet per second. That was one third of all the water coming down the West Fork between Humble and Kingwood. All by itself, that 79,000 CFS would have been the ninth largest flood in West Fork history. And that made the difference between flooding and not flooding for thousands of homes and businesses near the lake.
During Harvey, the peak flow over the spillway was five times the average flow over Niagra Falls. A wall of water 11 feet tall cascaded over the spillway above. Enough to fill NRG stadium in 3.5 minutes.
Floodgate Meeting Details
See the meeting details below.
Thursday, July 8, 2021
At the Kingwood Community Center (4102 Rustic Woods)
Doors Open 5:30 PM
Dredging Update Starts 5:45 PM
Gate Update Starts at 6 PM
Chief Recovery Officer, Stephen Costello, will provide a very brief update on Lake Houston Dredging operations at 5:45 p.m. before the Spillway Improvement Project program begins.
The program to discuss the Lake Houston Dam Spillway Improvement Project will start at 6:00 p.m. and conclude at 7:45 p.m. But don’t worry about sitting through a 2 hour meeting.
The main presentation by Black & Veatch, the project engineers, will be followed by a short Q&A session. The meeting will then transition into breakout sessions. Breakout tables will let residents engage with project management staff and engineers in small groups to ask more detailed questions.
Project Benefits
The Lake Houston Dam Spillway project will increase the outflow capacity of the Lake Houston Dam. The project proposes installing new crest gates in the existing uncontrolled spillway. This will allow for a rapid decrease of water levels in Lake Houston in advance of storm events to prevent or reduce upstream flooding. Engineers estimate the recommended alternative could help about 35,000 residents and 5,000 structures. It’s important for people to understand that if they flooded from streams or channels far from the lake during Harvey, this may not help them.
Funding
A Federal Emergency Management Agency (FEMA) Hazard Mitigation Grant Program provides $4.3 million for engineering and positions the city to receive another $42.7 million for construction.
Posted by Bob Rehak on 7/6/2021 based on info provided by Dave Martin’s Office
1407 Days since Hurricane Harvey
Progress Report on New Flood Maps and Flood-Insurance-Risk Ratings
On June 29, 2021, Harris County Flood Control District (HCFCD) gave Commissioners an update on the progress of new flood maps and flood-insurance-risk ratings. The flood-map changes could become effective as early as late 2023. FEMA’s new Risk Rating 2.0 system for flood-insurance pricing will be phased in during the next few years. See details below.
MAAPnext About Half Complete
MAAPnext is Harris County’s Modeling, Assessment and Awareness Project. The purpose: to develop the next generation of flood maps and tools. It will provide a better assessment of flood risks for individual properties, and make the nature of those risks easier for property owners to understand.
One of the significant changes: the new maps will capture different types of flooding, such as street flooding. This is currently the biggest missing piece of the flood-risk rating picture, according to the MAAPnext project team.
The new maps will also come with individual property reports that estimate flood depth, water-surface elevations, annual-chance of flooding grids, and 30-year chance of flooding grids. That last will estimate your chance of flooding at least once during a 30-year mortgage. The flood map grids will also be more detailed. They will provide estimates down to the 3 ft X 3 ft level.
FEMA and Harris County expect to have:
The earliest likely date that the new rate maps could become effective: late 2023.
Understanding FEMA’s Risk Rating 2.0
Risk Rating 2.0 is a massive FEMA effort to put the National Flood Insurance Program (NFIP) on a sound actuarial footing.
FEMA is updating the National Flood Insurance Program‘s (NFIP) risk rating methodology through the implementation of a new pricing methodology called Risk Rating 2.0. The methodology leverages industry best practices and cutting-edge technology to enable FEMA to deliver rates that are actuarily sound, equitable, easier to understand and better reflect a property’s flood risk.
More Risk Factors Considered
Elevations, flood-hazard zones, and rating tables will no longer be the only metrics used in calculating the flood-insurance premium for a property. For example, premiums will be distributed across all policyholders based on home values and a property’s unique flood risk. FEMA will also consider flood frequency, multiple flood types—river overflow, storm surge, coastal erosion and heavy rainfall—and distance to a water source along with property characteristics such as elevation and the cost to rebuild.
More Equitable Rates
Currently, many policyholders with lower-value homes are paying more than they should and policyholders with higher-value homes are paying less than they should.
That said, FEMA expects 87% of single-family homes to see a flood-insurance-premium increase of about $120 per year. Another 4% could see an increase of about $121 to $360 per year. Finally, 9% could see a decrease of up to $1,200 per year.
Phased Implementation
Beginning October 1 this year:
Starting in April 2022:
Contact your flood insurance agent to clarify all timing, rate and discount questions.
How Does MAAPnext Factor into Risk Rating 2.0?
Harris County Flood Control District in partnership with FEMA lead the MAAPnext effort to revise flood insurance rate maps. FEMA alone leads the Risk Rating 2.0 effort to calculate new flood insurance rates. The maps will help calculate new premiums.
For more information, visit the MAAPnext website or the Risk Rating 2.0 section of FEMA’s.
Posted by Bob Rehak on July 4, 2021 based on information from HCFCD and FEMA
1405 Days since Hurricane Harvey
Preliminary Engineering Contracts Approved for Two Kingwood Drainage Improvements
On June 29, 2021, Harris County Commissioners approved two contracts for preliminary engineering on Taylor Gully and the Kingwood Diversion Ditch. The Taylor Gully project includes looking at Woodridge Village in Montgomery County to possibly expand detention-pond capacity there. See more below.
Taylor Gully Project
Harris County Flood Control District (HCFCD) awarded Idcus, Inc. a $180,555 preliminary engineering contract to develop up to five conceptual alternative scenarios for modifying Taylor Gully. HCFCD and Idcus will then select three scenarios for more detailed analysis. Idcus must perform the work within 300 days of the Notice to Proceed.
The alternative modeling scenarios may include:
Deliverables for the alternatives include:
The scope also includes, when necessary:
Finally, Idcus will hold two public engagement meetings near the beginning and end of the project and consult with community groups such as KSA.
Kingwood Diversion Ditch
HCFCD entered into a contract with Neel-Schaffer, Inc. for $437,685 for preliminary engineering on the Kingwood Diversion Ditch. Within 300 days,Neel-Schaffer must:
Walnut Lane and Deer Ridge Estates Blvd.
HCFCD may also require Neel-Schaffer to provide addition services when necessary, such as:
For Complete Text of Contracts…
The first half of each link below contains contract details such as compensation. The second half contains the scope of work.
They were items 146 and 147 respectively on the agenda for the 6/29/21 Commissioner’s Court meeting.
Next Steps
In general, the critical path for each of these projects will follow the project-lifecycle pattern of all HCFCD projects.
HCFCD will:
These were two of many such contracts approved in the last Commissioners Court meeting.
Both came out of the Kingwood Drainage analysis. More on projects affecting other parts of the Lake Houston Area in future posts.
Posted by Bob Rehak on 7/3/2021
1404 Days after Hurricane Harvey