Because the Laurel Springs RV Resort was grandfathered under old drainage regulations, it got away with building a detention pond that was half the size required by current regulations.
But assuming the developers were just shrewd businessmen who legally and successfully exploited the system, did they follow the rest of the rules? Let’s look at two other things.
The percentage of impervious cover on the site
How the number of parking spots increased 25% without the impervious cover increasing.
Laurel Springs RV Resort as of 10/22/22. The contractor still has one more “pour” to complete the concrete in the far upper right of the image.
Were Impervious Cover Calculations Correct?
Detention-pond volume calculations begin with impervious cover (i.e., land covered by concrete plus the entire detention pond area). See below.
The total site covers 20.032 acres. The proposed impervious portion, they claim, covers 13.349 acres. That works out to 66.6%. So one third of the site should be grass, trees and other vegetation. But since the entire 5-acre detention pond counts as impervious, mathematically, the remainder of the site can have no more than about 60% concrete and still comply with the percentage they promised.
But just eyeballing that trapezoidal area in the photo above, it seems much more than 60% is covered with concrete.
If my eyeball assessment is correct, then the detention pond is even more undersized than I initially thought because the percentage of impervious cover has increased and with it the amount of runoff.
I wish the developer would show us the basis for those calculations.
Plans Show Increase in Density With No Increase In Impervious Cover
The developer’s permit allows 182 RV spaces, but the plans show 226 – about a 24% increase. However, the impervious cover shown on the plans before and after the permit approval didnot change. That could also affect detention pond capacity requirements. And explain why the percentage of concrete appears higher than they claim.
Why Underestimate Impervious Cover?
Why would a developer underestimate the amount of impervious cover? Two reasons:
It would make the detention pond smaller and thus allow the remaining property to produce more income.
I’m not alleging they did anything illegal. I’m just saying that much more than 60% of that trapezoid in the photo above appears to be concrete and I sure would like to see how they arrived at their figures. I requested the drainage analysis twice and never got it. That should tell you something.
Posted by Bob Rehak on 10/23/22
1881 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
In January of this year, when they kicked off construction at the Preserve at Woodridge, I posted about the Montgomery County development claiming 65% impervious cover. It’s time to get out the ruler. See pictures below taken on 10/22/22.
Looking SE across Woodridge Parkway toward Kingwood Park High School out of frame at the top.
I felt at the time that the 65% claim didn’t pass eyeball test. I feel even more strongly about that now.
The Preserve at Woodridge will boast 131 homelets on about 10 acres. Looking west toward St. Martha Catholic Church.Some are just 4 feet apart. The wider row at the top will be divided into backyards.
The walkway going left to right through the bottom of the frame will be people’s front yards. Not quite southern mansions. But there’s plenty of room for a daffodil and a fire hose.
How Impervious Cover Can Contribute to Flooding
The higher the percentage of impervious cover, the less stormwater soaks into the ground. It runs off faster. And without sufficient detention pond capacity, flood peaks build higher.
That’s why I’m so concerned about the accuracy of the 65% estimate. The capacity of their detention pond was configured based on one third grass.
The lack of green space upstream is a growing issue downstream. Our drainage systems never anticipated this kind of density.
Areas with high rates of impervious cover, as determined by Descartes Labs.Black dots represent growth of impervious cover. Note the ring around Houston.
To put 65% impervious cover in perspective (assuming the developer’s estimate is accurate), nationwide only about 4.4% of the land in the U.S. has more than 40%. And usually only shopping malls and high-density apartment complexes have more than 65%.
Current drainage capacity rarely anticipates development like this. That’s why so much of Houston’s drainage infrastructure struggles to function properly in heavy rains. It’s also why in 2010, the City of Houston instituted a drainage fee based on the percentage of impervious cover. The purpose: to raise money to repair/upgrade antiquated drainage systems taxed by overdevelopment and to encourage developers to leave more green space.
Close inspection of this site shows that the developer did leave leave one row of pet-friendly trees along the northern side.
Somebody screwed up. They could have squeezed another row of homes in there.
Posted by Bob Rehak on 10/22/22
1880 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/10/20221022-DJI_0961.jpg?fit=1200%2C799&ssl=17991200adminadmin2022-10-22 16:45:342022-10-22 16:59:0165% Impervious Cover? Get Out the Ruler!
Data obtained via a FOIA Request shows that the watersheds where three top Harris County Democrats live are consuming 25% of flood-bond funding. Meanwhile, those Democrats are starving their Republican opponents and supportersalike of flood-mitigation money.
Harris County Flood Control’s website also shows there are currently no active capital-improvement construction projects in Kingwood, Humble, Huffman, Spring, Atascocita or Crosby. Yet half of all active construction project dollars are going to just three watersheds where the three top Democrat leaders live.
Largest Watershed Among Least Funded
Harris County’s largest watershed – the 215-square-mile San Jacinto – ranks #18 out of 23 watersheds in flood-mitigation funding per square mile under Lina Hidalgo’s administration. That’s according to data obtained from Harris County via a FOIA Request that shows funding through the third quarter of 2022. Neighboring watersheds in the Republican-leaning far northeast part of the county are similarly starved for funding.
Watershed Map of Harris County
Consistent Funding Bias
San Jacinto-watershed residents are not alone. Spring, Jackson and Luce watersheds comprise most of the rest of the northeast portion of the county. They are among the least funded watersheds under Hidalgo whether you measure “total flood-mitigation funding” or “funding per square mile.”
The San Jacinto received only $37 million during Hidalgo’s administration. Spring received $10.1 million. Jackson received just $2.7 million. And Luce received a minuscule $1 million.
These watersheds respectively rank:
#12, #18, #20 and #23 in total flood-mitigation funding
#18, #19, #21 and #23 in funding per square mile.
Backyard Fringe Benefits
Contrast that with the following totals under Hidalgo in three other watersheds:
Buffalo Bayou (91.7 square miles) is less than half the size of the San Jacinto Watershed. It received more – $39.5 million. That’s where County Judge Lina Hidalgo lives. It ranks #12 in total post-Harvey funding.
White Oak Bayou ranks #6 in total post-Harvey funding at $94 million. It’s half the size of the San Jacinto (111 sq. mi), but received 2.5X more flood-mitigation funding. Precinct 2 Commissioner Adrian Garcia lives there.
Brays Bayou ranks #1 in total post-Harvey funding at $171 million – more than 8 times as much as the San Jacinto. Yet it’s only a little more than half the size (114.2 square miles). That’s where Precinct 1 Commissioner Rodney Ellis lives.
Hidalgo, Garcia and Ellis spent $305 million in the three watersheds where they live. That’s six times more than the $51 million spent for the San Jacinto, Spring, Jackson and Luce Watersheds.
Now, let’s compare what the watersheds above have received in fundingper square mile under Hidalgo:
Brays = $1.5 million
White Oak = $845 thousand
Buffalo = $431 thousand
San Jacinto = $172 thousand
Spring = $169 thousand
Jackson = $104 thousand
Luce = $45 thousand
The first three above comprise 246 square miles and received $305 million under Hidalgo to date. The bottom four comprise 323 square miles and received $51 million.
So under Hidalgo, Brays, White Oak and Buffalo averaged $1.2 million per square mile. Meanwhile, the Republican-leaning San Jacinto, Spring, Jackson and Luce watersheds averaged only $158 thousand per square mile! That’s about one eighth as much.
Notice a trend? I thought the three Democrats were trying to help the poor with their equity plan. Were they really just trying to punish political opponents through funding inequities? Looking out for themselves all along? Or both?
Parts of the San Jacinto and Spring Creek watersheds experienced water more than 20 feet above flood stage during Harvey while parts of Brays and White Oak didn’t even come out of their banks.
No Active Capital Improvement Projects in Lake Houston Area
And to think! Hidalgo, Ellis and Garcia conned dozens of members of the Northeast Action Collective into requesting Commissioners Court to shift money from Kingwood to Halls Bayou. They said Kingwood was getting all the money! It hasn’t and isn’t.
At the moment, Harris County Flood Control shows NO active capital improvement construction projects in Kingwood, Huffman, Crosby, Humble, Atascocita or Spring.
Yet HCFCD is spending $224 million elsewhere in the county on active construction. That includes another $71 million in Brays and $36 million in White Oak for another $107 million total. Almost HALF of the active construction projects in the entire county are going to the watersheds where Ellis and Garcia live!
And that’s in addition to the $305 million that White Oak, Brays and Buffalo already received under Hidalgo.
We have a chance to do something about these inequities starting in a few days. Early voting starts on October 24. You can find polling places here.
Posted by Bob Rehak on October 20, 2022and updated 10/21 to include spreadsheets and improve clarity.
1878 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2022/10/20210613-Screen-Shot-2021-06-13-at-3.48.47-PM-2.jpg?fit=1200%2C927&ssl=19271200adminadmin2022-10-20 22:26:462022-10-21 15:06:54The Real Inequities in Flood-Mitigation Funding
66% Impervious Cover? Really?
Because the Laurel Springs RV Resort was grandfathered under old drainage regulations, it got away with building a detention pond that was half the size required by current regulations.
But assuming the developers were just shrewd businessmen who legally and successfully exploited the system, did they follow the rest of the rules? Let’s look at two other things.
Were Impervious Cover Calculations Correct?
Detention-pond volume calculations begin with impervious cover (i.e., land covered by concrete plus the entire detention pond area). See below.
The total site covers 20.032 acres. The proposed impervious portion, they claim, covers 13.349 acres. That works out to 66.6%. So one third of the site should be grass, trees and other vegetation. But since the entire 5-acre detention pond counts as impervious, mathematically, the remainder of the site can have no more than about 60% concrete and still comply with the percentage they promised.
But just eyeballing that trapezoidal area in the photo above, it seems much more than 60% is covered with concrete.
If my eyeball assessment is correct, then the detention pond is even more undersized than I initially thought because the percentage of impervious cover has increased and with it the amount of runoff.
I wish the developer would show us the basis for those calculations.
Plans Show Increase in Density With No Increase In Impervious Cover
The developer’s permit allows 182 RV spaces, but the plans show 226 – about a 24% increase. However, the impervious cover shown on the plans before and after the permit approval did not change. That could also affect detention pond capacity requirements. And explain why the percentage of concrete appears higher than they claim.
Why Underestimate Impervious Cover?
Why would a developer underestimate the amount of impervious cover? Two reasons:
I’m not alleging they did anything illegal. I’m just saying that much more than 60% of that trapezoid in the photo above appears to be concrete and I sure would like to see how they arrived at their figures. I requested the drainage analysis twice and never got it. That should tell you something.
Posted by Bob Rehak on 10/23/22
1881 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
65% Impervious Cover? Get Out the Ruler!
In January of this year, when they kicked off construction at the Preserve at Woodridge, I posted about the Montgomery County development claiming 65% impervious cover. It’s time to get out the ruler. See pictures below taken on 10/22/22.
I felt at the time that the 65% claim didn’t pass eyeball test. I feel even more strongly about that now.
The walkway going left to right through the bottom of the frame will be people’s front yards. Not quite southern mansions. But there’s plenty of room for a daffodil and a fire hose.
How Impervious Cover Can Contribute to Flooding
The higher the percentage of impervious cover, the less stormwater soaks into the ground. It runs off faster. And without sufficient detention pond capacity, flood peaks build higher.
That’s why I’m so concerned about the accuracy of the 65% estimate. The capacity of their detention pond was configured based on one third grass.
The lack of green space upstream is a growing issue downstream. Our drainage systems never anticipated this kind of density.
And don’t forget, this development also based its drainage calculations on pre-Atlas 14 rainfall rates.
Growth of Impervious Cover
USGS says one third of Harris County is now impervious cover. With more developments like this, the southern part of Montgomery County could one day surpass Harris County!
In December, the New York Times published a story about a company called Descartes Labs, which had trained computers to scan satellite images to detect changes in impervious cover. Descartes found that Texas had 9 of the top 20 counties in the U.S. when ranked by the growth of impervious cover.
To put 65% impervious cover in perspective (assuming the developer’s estimate is accurate), nationwide only about 4.4% of the land in the U.S. has more than 40%. And usually only shopping malls and high-density apartment complexes have more than 65%.
Current drainage capacity rarely anticipates development like this. That’s why so much of Houston’s drainage infrastructure struggles to function properly in heavy rains. It’s also why in 2010, the City of Houston instituted a drainage fee based on the percentage of impervious cover. The purpose: to raise money to repair/upgrade antiquated drainage systems taxed by overdevelopment and to encourage developers to leave more green space.
Close inspection of this site shows that the developer did leave leave one row of pet-friendly trees along the northern side.
Posted by Bob Rehak on 10/22/22
1880 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.
The Real Inequities in Flood-Mitigation Funding
Data obtained via a FOIA Request shows that the watersheds where three top Harris County Democrats live are consuming 25% of flood-bond funding. Meanwhile, those Democrats are starving their Republican opponents and supporters alike of flood-mitigation money.
Harris County Flood Control’s website also shows there are currently no active capital-improvement construction projects in Kingwood, Humble, Huffman, Spring, Atascocita or Crosby. Yet half of all active construction project dollars are going to just three watersheds where the three top Democrat leaders live.
Largest Watershed Among Least Funded
Harris County’s largest watershed – the 215-square-mile San Jacinto – ranks #18 out of 23 watersheds in flood-mitigation funding per square mile under Lina Hidalgo’s administration. That’s according to data obtained from Harris County via a FOIA Request that shows funding through the third quarter of 2022. Neighboring watersheds in the Republican-leaning far northeast part of the county are similarly starved for funding.
Consistent Funding Bias
San Jacinto-watershed residents are not alone. Spring, Jackson and Luce watersheds comprise most of the rest of the northeast portion of the county. They are among the least funded watersheds under Hidalgo whether you measure “total flood-mitigation funding” or “funding per square mile.”
The San Jacinto received only $37 million during Hidalgo’s administration. Spring received $10.1 million. Jackson received just $2.7 million. And Luce received a minuscule $1 million.
These watersheds respectively rank:
Backyard Fringe Benefits
Contrast that with the following totals under Hidalgo in three other watersheds:
Buffalo, White Oak and Brays watersheds are all in the lead for flood-tunnels, too. Those could add billions more to the backyard benefits received by Hidalgo, Ellis and Garcia!
Funding-Per-Square Mile Comparison
Now, let’s compare what the watersheds above have received in funding per square mile under Hidalgo:
The first three above comprise 246 square miles and received $305 million under Hidalgo to date. The bottom four comprise 323 square miles and received $51 million.
Notice a trend? I thought the three Democrats were trying to help the poor with their equity plan. Were they really just trying to punish political opponents through funding inequities? Looking out for themselves all along? Or both?
Parts of the San Jacinto and Spring Creek watersheds experienced water more than 20 feet above flood stage during Harvey while parts of Brays and White Oak didn’t even come out of their banks.
No Active Capital Improvement Projects in Lake Houston Area
And to think! Hidalgo, Ellis and Garcia conned dozens of members of the Northeast Action Collective into requesting Commissioners Court to shift money from Kingwood to Halls Bayou. They said Kingwood was getting all the money! It hasn’t and isn’t.
Yet HCFCD is spending $224 million elsewhere in the county on active construction. That includes another $71 million in Brays and $36 million in White Oak for another $107 million total. Almost HALF of the active construction projects in the entire county are going to the watersheds where Ellis and Garcia live!
And that’s in addition to the $305 million that White Oak, Brays and Buffalo already received under Hidalgo.
It takes a lot of chutzpah to spend $412 million protecting your own homes while Low-to-Moderate Income residents elsewhere flood. Now I know why the three pretend Kingwood is getting ALL the money. It’s a diversionary tactic.
More news to follow as I continue to analyze the latest spending data through the third quarter of 2022.
For the complete response provided by Harris County to my FOIA Request, click here.
This summary worksheet combines funding with other factors such as population, area, damage, etc.
What You Can Do
We have a chance to do something about these inequities starting in a few days. Early voting starts on October 24. You can find polling places here.
Posted by Bob Rehak on October 20, 2022 and updated 10/21 to include spreadsheets and improve clarity.
1878 Days since Hurricane Harvey
The thoughts expressed in this post represent opinions on matters of public concern and safety. They are protected by the First Amendment of the US Constitution and the Anti-SLAPP Statute of the Great State of Texas.