In early April, the Coastal Water Authority (CWA) quietly finalized the scope of work for engineers working on adding more gates to the Lake Houston Dam. Engineering firm Black & Veatch’s contract was approved. And their work has now begun. Here’s what it involves.
Looking upstream at the Lake Houston Dam. Photo taken 11/4/2019.
The current gates on Lake Houston’s dam have one fifteenth the discharge capacity of Lake Conroe’s – 10,000 cfs vs. 150,000 cfs.
Additional gates could help synchronize the release rates of the two dams and thus reduce flood risk. More/bigger gates could lower the Lake Houston faster in advance of a storm and add width to the spillway during a storm. Both help reduce flooding.
Avoiding Unnecessary Releases
Currently, it takes several days to lower Lake Houston enough to significantly reduce flood risk. During that time, approaching storms can veer away or dissipate. So a conservation angle exists here, too. More gates release water faster. That lets CWA wait until weather-forecast certainty is higher before lowering the lake. And that, in turn, helps avoid unnecessary discharges and conserve water.
18-Month Project Starting from April 8th
The addition of gates is a three-year project broken into two 18-month phases.
Phase 1 involves preliminary design of conceptual alternatives, selecting the “best” based on criteria described below, and permitting.
The clock for Phase 1 started ticking on April 8, 2020, the day Black and Veatch’s contract was approved. Phase 1 should conclude in September 2021.
Phase 2 involves final design and construction. Assuming all goes well, we could have more discharge capacity at the Lake Houston dam by March 2023 at the earliest. However, there will be an evaluation period between the two phases that could push the completion date out further. Also…
Phase 2 Depends on Outcome of Phase 1
One objective of Phase 1 is to prove up the concept, the budget, and the benefit/cost ratio.
Proceeding to construction in Phase 2 will depend on the outcome of Phase 1. In Phase 1, engineers will examine several possible designs to determine the most effective alternative. They will consider flood reduction benefits, downstream impacts, cost, environmental impact, constructibility and more.
Then FEMA will evaluate the benefit/cost ratio of the winning design to ensure it meets or beats initial projections in the grant request.
If it does, FEMA will release money for Phase 2, the final design and construction.
If it doesn’t, the whole project could die.
FEMA does not guarantee Phase 2 funding at this time.
What Happens Now?
The scope of work document reveals who will do what in the next 18 months on the Lake Houston Spillway Improvement Project (LHSIP).
Objective: To relieve upstream flooding by increased discharge capacity that supports pre-releases.
Modifications could include (but are not limited to):
Additional crest gates on or adjacent to the existing dam or…
New, as-yet-unspecified hydraulic structures that provide for releases elsewhere on the embankment
The project will consider both upstream benefits and downstream impacts.
Looking downstream over the Lake Houston Dam in foreground gives you some idea of the courage that it requires to live or work below a dam.
After defining alternatives and constraints, the contractor, Black & Veatch, will analyze the alternatives to quantify and compare costs and benefits of each configuration.
Five Major Tasks in Phase 1
Preliminary engineering involves five major tasks:
Management plans
Hydrology and Hydraulic Modelling
Permitting
Field Investigation
Development of alternative concepts
Let’s look at each.
Management Plans
Black & Veatch will begin Phase 1 by developing project-, quality-, and risk-management plans.
H&H Studies
Hydrology and hydraulics (H&H) studies will evaluate the ability of the various concepts to reduce upstream flooding and downstream impacts. Black & Veatch will develop H&H models that combine both the San Jacinto River and Buffalo Bayou basins to evaluate downstream impacts of any dam.
The combined model will extend all the way to Galveston Bay and evaluate design alternatives for up to nine events:
2-, 10-, 50-, 100-, and 500-year storms
Extreme historic events (e.g. Harvey, Ike or Memorial Day), including at least one with storm-surge effects
A hypothetical Probable Maximum Precipitation event.
The process includes collecting, reviewing, adjusting and validating existing models before performing simulations.
Permitting Gauntlet
To save time, permitting will begin concurrently with design. The permitting schedule is aggressive and may spill over into Phase 2 as details are refined. Permitting includes (but is not limited to) coordination with federal, state and local agencies for:
Environmental Assessment
Environmental Impact Statement
Wetland delineations
Threatened and endangered (T&E) habitat assessment
T&E species-specific surveys
Migratory Bird Treaty Act (MBTA) surveys
Freshwater Mussel survey
Stormwater pollution prevention
Clean Water Act
Flood Plain Construction
The environmental team will also consider:
Topography and Soils Construction Impacts
Land Use
Indirect and Cumulative Impacts
Geology, Hydrology and Drainage
Sediment Quality
Vegetation
Air Quality
Invasive Species
Coastal Zone Management Wildlife and Endangered Species
Essential Fish Habitat
Existing Facilities and Utilities
Noise Quality
Socioeconomics
Traffic and Circulation
Waters of the U.S., including Wetlands
Environmental Justice
Cultural Resources (historical and archaeological)
Recreation
Floodplains
Visual/ Aesthetic Appeal
Water Quality
Hazardous Materials
Field Investigations
Black & Veatch will also conduct site surveys and a geotechnical investigation, complete with borings, to evaluate soil conditions, depth-to-water, permeability, and seepage control.
A bathymetry team will measure water depth and develop contour maps for an area that extends 500 feet upstream from the dam.
Preliminary Engineering/Conceptual Design
Finally, preliminary engineering will develop conceptual layouts and site plans for several alternatives.
This exercise will also evaluate areas of impact, site access and utilities, staging and borrow areas, dewatering extents, existing structure tie-in, general facilities layout, and downstream channel alignment.
These site plans will be used for costing and evaluating the feasibility for each alternative.
Criteria for Choosing Best Alternatives
The engineers will also develop an evaluation matrix that includes, but is not limited to:
Ability to meet project goals
Environmental clearance
Construction costs, including any environmental mitigation
Long-term operation and maintenance costs
Benefit/cost analysis
Risks in design, construction, and operation.
From all the feasible options, engineers will then chose the three best based on:
Cost
Upstream impact
Downstream impact
Environmental impact
Permitting requirements
Constructibility
Timing on Phase 2
Assuming we get to Phase 2, the second 18 months may not start immediately. FEMA will need time to evaluate Phase 1 results. And the CWA will need to develop bid specs, bid the job, select a winner, and develop a contract with a scope of work, just as they did for Phase 1. That could talk several months and push completion well into 2023.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/05/20191104-RJR_4790.jpg?fit=1200%2C800&ssl=18001200adminadmin2020-05-01 12:22:242020-05-01 15:57:06Preliminary Engineering Starts for Adding More Gates to Lake Houston Dam
Have you ever been flooded by a new development? Did you learn about the development AFTER bulldozers started knocking down trees? There’s a much better way. The City of Houston offers several tools to help you track applications for new developments long before the bulldozers start belching diesel fumes.
City of Houston PlatTracker map for Northeast Houston and Lake Houston Areaas of 4/30/2020
If someone has applied for a permit to develop a piece of land, it will show up on the map. Notice the purple areas along the West Fork west of the Kingwood Country Club. That’s how I learned about the reactivation of Romerica’s plans.
The color of the parcels corresponds to the stage of the application. Clicking on the parcel pulls up an information panel that gives you more history including the date the developer submitted the application, when it will be reviewed, the review stage, and more.
Zoom in and out as wide as you want. Just be aware that the wider you zoom, the longer it takes the screen to refill with all the plat information. There’s a lot more of it!
As I zoomed out around Kingwood, the number of new developments that I was unaware of shocked me. If you want to see humongous changes, look south of Humble, east to Huffman, west to Spring, and north to Porter and New Caney. Kingwood is a relative island of quiet in a sea of change.
Other Related Interactive Maps
The PlatTracker Plat Map is just one of thirty other interactive maps that you can use to explore and monitor the City around you. They include, but are not limited to:
Land use
Water flood hazards
Governmental boundaries
Demographics
Annexation history
Address and Permit Information
PlatTracker Agenda/Spreadsheet
Once you have identified a development you are interested in, another site can help you learn more about when the Houston Planning Commission will consider applications related to the site. It will also give you:
Subdivision plat name
Application Number
Date Submitted
Subdivision type
Variance requests
Location on the Commission’s agenda
County
Council district
Precinct
Census Tract
Zip Code
School district
TIRZ (tax increment reinvestment zone) if any
Superneighborhood Council
Land Use
Number of Lots
Acreage
Appraisal district numbers
Developer Name
Applicant Company
Applicants Name
Phone Number
You can even download the latest documents related to the application.
Wow. Everything you need to put your mind at ease. Or stage a protest. All at your fingertips.
These are great tools for concerned residents and citizen activists.
I’m sure a lot of Elm Grove residents wish they had known about these tools before the bulldozers started knocking down trees in Woodridge Village.
For future reference, I’ve added links for these sites within ReduceFlooding’s Links Page under the Community heading.
Posted by Bob Rehak on 4/30/2020
975 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/04/PLATTRACKER-LAKE-HOUSTON.jpg?fit=1200%2C743&ssl=17431200adminadmin2020-04-30 19:43:042020-04-30 20:10:15Tools to Track Permit Applications for Developments Near You
In a meeting today, the Houston Planning Commission deferred automatic approval of the general plan for Orchard Seeded Ranches by taking the item off the consent agenda. The Commission then asked the developer to consult with the City Engineer; the Planning and Development Department; and Harris County Flood Control before bringing further requests back to the Commission.
Taking the item off today’s consent agenda should send a strong signal to the developer that rough waters lie ahead. Any proposal will likely be debated publicly when/if the developer returns.
History of Project
Last year, Romerica filed a permit application to build 5,000 condos and several high-rises up to 50 stories tall on 331 acres near the floodway of the San Jacinto West Fork. After a record number of people and groups filed protests with the Army Corps of Engineers, the Corps withdrew the application. But now the developer is back – with a different name – Orchard Seeded Ranches. However, Harris County Appraisal District indicates that the same people still own the land.
For orientation, the developed area in the middle is the Barrington. The line down the west side is Woodland Hills Drive. And the river at the bottom is the West Fork.
Filing a “general plan” like this is the first step in developing property. The developer has not yet submitted detailed plats showing construction details.
Virtually Entire Development in Floodway or Floodplain
About half of the Orchard Seeded Ranches lies in the floodway of the San Jacinto West Fork. FEMA defines floodways as the main current of a river during a flood. In the map below, that includes everything beneath the red line.
Purple area = Orchard Seeded Ranches. Red line = extent of floodway north of San Jacinto West Fork.Virtually half of subdivision would be in floodway.
Virtually all of the purple area above the red line lies in the floodplain. FEMA defines a floodplain as “storage” for water during a flood. That means water covers the land without moving rapidly.
I created the map above by combining the area to be developed with the FEMA flood map below.
Every part of the proposed development contains wetlands to some extent.
Note how the areas around the Barrington and River Grove Park are filled with wetlands (green areas). From US Fish and Wildlife Service National Wetlands Mapper.Active bald eagle nest adjacent to development. Photo courtesy of Emily Murphy.
US Fish and Wildlife documented another eagle’s nest on the developer’s property. And the Balcom family, which lives near the western edge of the developer’s property, regularly photographs eagles from their balcony.
What’s in a Name
The name sounds as if the development would be lower density than the 50-story high-rises previously planned. But you never know. In the development business, names often have more evocative than literal significance. Look at the Houston Heights. Bridgeland (on the prairie). Mount Houston. You get the idea.
Community Considerations
Whatever the development is, when and if the developer returns to the Planning Commission, we should not forget that:
When floodplain maps are redrawn using Atlas-14 data, that floodway will likely expand significantly.
High water during Harvey at Balcom house on River Bend reached the second story.
A Less Risky, Less Costly Alternative
All of these factors will increase the risk and cost of any development.
Light pole near River Bend in North Shore as Harvey receded. Note the “wet marks” several feet up on pole. Photo by Jim Balcom.
The safest, sanest course for the developer – before putting more money at risk –would be to meet with community representatives about:
Purchasing this land
Putting a conservation easement on it
Letting it revert to nature and turning it into park land
Harris County Flood Control District has $175 million allocated in the flood bond for partnership projects with “Municipalities, Authorities, and Other Districts in Harris County.” See item Z100-00-00-MUNI.
That money could help purchase such property and turn it into green space forever. KSA, the Lake Houston Chamber, civic leaders and residents should get behind that idea. Judging by the response to Romerica’s last offering, it’s clear that residents would much rather see this area turned into parks than see the San Jacinto turn it into blight.
Preliminary Engineering Starts for Adding More Gates to Lake Houston Dam
In early April, the Coastal Water Authority (CWA) quietly finalized the scope of work for engineers working on adding more gates to the Lake Houston Dam. Engineering firm Black & Veatch’s contract was approved. And their work has now begun. Here’s what it involves.
Background: Why More Gates?
After Hurricane Harvey, a pilot study by HCFCD and Freese & Nichols showed additional gates could have helped lower floodwaters.
The current gates on Lake Houston’s dam have one fifteenth the discharge capacity of Lake Conroe’s – 10,000 cfs vs. 150,000 cfs.
Additional gates could help synchronize the release rates of the two dams and thus reduce flood risk. More/bigger gates could lower the Lake Houston faster in advance of a storm and add width to the spillway during a storm. Both help reduce flooding.
Avoiding Unnecessary Releases
Currently, it takes several days to lower Lake Houston enough to significantly reduce flood risk. During that time, approaching storms can veer away or dissipate. So a conservation angle exists here, too. More gates release water faster. That lets CWA wait until weather-forecast certainty is higher before lowering the lake. And that, in turn, helps avoid unnecessary discharges and conserve water.
18-Month Project Starting from April 8th
The addition of gates is a three-year project broken into two 18-month phases.
Phase 1 involves preliminary design of conceptual alternatives, selecting the “best” based on criteria described below, and permitting.
Phase 2 involves final design and construction. Assuming all goes well, we could have more discharge capacity at the Lake Houston dam by March 2023 at the earliest. However, there will be an evaluation period between the two phases that could push the completion date out further. Also…
Phase 2 Depends on Outcome of Phase 1
One objective of Phase 1 is to prove up the concept, the budget, and the benefit/cost ratio.
Proceeding to construction in Phase 2 will depend on the outcome of Phase 1. In Phase 1, engineers will examine several possible designs to determine the most effective alternative. They will consider flood reduction benefits, downstream impacts, cost, environmental impact, constructibility and more.
Then FEMA will evaluate the benefit/cost ratio of the winning design to ensure it meets or beats initial projections in the grant request.
FEMA does not guarantee Phase 2 funding at this time.
What Happens Now?
The scope of work document reveals who will do what in the next 18 months on the Lake Houston Spillway Improvement Project (LHSIP).
Modifications could include (but are not limited to):
Unlike tainter gates which swing up from a radial arm, crest gates swing down from a bottom hinge.
After defining alternatives and constraints, the contractor, Black & Veatch, will analyze the alternatives to quantify and compare costs and benefits of each configuration.
Five Major Tasks in Phase 1
Preliminary engineering involves five major tasks:
Let’s look at each.
Management Plans
Black & Veatch will begin Phase 1 by developing project-, quality-, and risk-management plans.
H&H Studies
Hydrology and hydraulics (H&H) studies will evaluate the ability of the various concepts to reduce upstream flooding and downstream impacts. Black & Veatch will develop H&H models that combine both the San Jacinto River and Buffalo Bayou basins to evaluate downstream impacts of any dam.
The combined model will extend all the way to Galveston Bay and evaluate design alternatives for up to nine events:
The process includes collecting, reviewing, adjusting and validating existing models before performing simulations.
Permitting Gauntlet
To save time, permitting will begin concurrently with design. The permitting schedule is aggressive and may spill over into Phase 2 as details are refined. Permitting includes (but is not limited to) coordination with federal, state and local agencies for:
The environmental team will also consider:
Field Investigations
Black & Veatch will also conduct site surveys and a geotechnical investigation, complete with borings, to evaluate soil conditions, depth-to-water, permeability, and seepage control.
A bathymetry team will measure water depth and develop contour maps for an area that extends 500 feet upstream from the dam.
Preliminary Engineering/Conceptual Design
Finally, preliminary engineering will develop conceptual layouts and site plans for several alternatives.
This exercise will also evaluate areas of impact, site access and utilities, staging and borrow areas, dewatering extents, existing structure tie-in, general facilities layout, and downstream channel alignment.
These site plans will be used for costing and evaluating the feasibility for each alternative.
Criteria for Choosing Best Alternatives
The engineers will also develop an evaluation matrix that includes, but is not limited to:
From all the feasible options, engineers will then chose the three best based on:
Timing on Phase 2
Assuming we get to Phase 2, the second 18 months may not start immediately. FEMA will need time to evaluate Phase 1 results. And the CWA will need to develop bid specs, bid the job, select a winner, and develop a contract with a scope of work, just as they did for Phase 1. That could talk several months and push completion well into 2023.
For More Information
All that, just to figure out what to do! To read the full 27-page Scope of Work, click here. I will also post this document for future reference in the Reports page of this web site under a new tab titled Lake Houston Dam Spillway Improvement Project.
Posted by Bob Rehak on 5/1/2020
976 Days after Hurricane Harvey
Tools to Track Permit Applications for Developments Near You
Have you ever been flooded by a new development? Did you learn about the development AFTER bulldozers started knocking down trees? There’s a much better way. The City of Houston offers several tools to help you track applications for new developments long before the bulldozers start belching diesel fumes.
GIS PlatTracker Map
The first is an interactive, color coded GIS map that shows the status of all permit applications in the City and its ETJ (extra-territorial jurisdiction). The ETJ extends well beyond the boundaries of the City. Going up 45, it extends to 242. Going up 59, it extends to Roman Forest.
If someone has applied for a permit to develop a piece of land, it will show up on the map. Notice the purple areas along the West Fork west of the Kingwood Country Club. That’s how I learned about the reactivation of Romerica’s plans.
The color of the parcels corresponds to the stage of the application. Clicking on the parcel pulls up an information panel that gives you more history including the date the developer submitted the application, when it will be reviewed, the review stage, and more.
Zoom in and out as wide as you want. Just be aware that the wider you zoom, the longer it takes the screen to refill with all the plat information. There’s a lot more of it!
As I zoomed out around Kingwood, the number of new developments that I was unaware of shocked me. If you want to see humongous changes, look south of Humble, east to Huffman, west to Spring, and north to Porter and New Caney. Kingwood is a relative island of quiet in a sea of change.
Other Related Interactive Maps
The PlatTracker Plat Map is just one of thirty other interactive maps that you can use to explore and monitor the City around you. They include, but are not limited to:
PlatTracker Agenda/Spreadsheet
Once you have identified a development you are interested in, another site can help you learn more about when the Houston Planning Commission will consider applications related to the site. It will also give you:
For Planning Commission meeting dates and agendas, click here.
Situational Awareness for Concerned Citizens
Wow. Everything you need to put your mind at ease. Or stage a protest. All at your fingertips.
These are great tools for concerned residents and citizen activists.
For future reference, I’ve added links for these sites within ReduceFlooding’s Links Page under the Community heading.
Posted by Bob Rehak on 4/30/2020
975 Days since Hurricane Harvey
Houston Planning Commission defers approval of “Orchard Seeded Ranches”
In a meeting today, the Houston Planning Commission deferred automatic approval of the general plan for Orchard Seeded Ranches by taking the item off the consent agenda. The Commission then asked the developer to consult with the City Engineer; the Planning and Development Department; and Harris County Flood Control before bringing further requests back to the Commission.
Taking the item off today’s consent agenda should send a strong signal to the developer that rough waters lie ahead. Any proposal will likely be debated publicly when/if the developer returns.
History of Project
Last year, Romerica filed a permit application to build 5,000 condos and several high-rises up to 50 stories tall on 331 acres near the floodway of the San Jacinto West Fork. After a record number of people and groups filed protests with the Army Corps of Engineers, the Corps withdrew the application. But now the developer is back – with a different name – Orchard Seeded Ranches. However, Harris County Appraisal District indicates that the same people still own the land.
Location of Property
The property is identical to the property Romerica tried to develop as The Herons of Kingwood last year. The General Plan below was downloaded from the City of Houston’s PlatTracker website.
For orientation, the developed area in the middle is the Barrington. The line down the west side is Woodland Hills Drive. And the river at the bottom is the West Fork.
Filing a “general plan” like this is the first step in developing property. The developer has not yet submitted detailed plats showing construction details.
Virtually Entire Development in Floodway or Floodplain
About half of the Orchard Seeded Ranches lies in the floodway of the San Jacinto West Fork. FEMA defines floodways as the main current of a river during a flood. In the map below, that includes everything beneath the red line.
Virtually all of the purple area above the red line lies in the floodplain. FEMA defines a floodplain as “storage” for water during a flood. That means water covers the land without moving rapidly.
I created the map above by combining the area to be developed with the FEMA flood map below.
Wetlands Issues Also Abound
Every part of the proposed development contains wetlands to some extent.
US Fish and Wildlife documented another eagle’s nest on the developer’s property. And the Balcom family, which lives near the western edge of the developer’s property, regularly photographs eagles from their balcony.
What’s in a Name
The name sounds as if the development would be lower density than the 50-story high-rises previously planned. But you never know. In the development business, names often have more evocative than literal significance. Look at the Houston Heights. Bridgeland (on the prairie). Mount Houston. You get the idea.
Community Considerations
Whatever the development is, when and if the developer returns to the Planning Commission, we should not forget that:
A Less Risky, Less Costly Alternative
All of these factors will increase the risk and cost of any development.
The safest, sanest course for the developer – before putting more money at risk –would be to meet with community representatives about:
Harris County Flood Control District has $175 million allocated in the flood bond for partnership projects with “Municipalities, Authorities, and Other Districts in Harris County.” See item Z100-00-00-MUNI.
That money could help purchase such property and turn it into green space forever. KSA, the Lake Houston Chamber, civic leaders and residents should get behind that idea. Judging by the response to Romerica’s last offering, it’s clear that residents would much rather see this area turned into parks than see the San Jacinto turn it into blight.
Posted by Bob Rehak on 4/30/2020
975 Days after Hurricane Harvey