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Detention Pond Construction: Montgomery vs. Harris County

Below are aerial images from two new developments under construction. They show two detention ponds in two different counties. Can you tell which is in Montgomery County and which is in Harris County? I took both photos on the same day, 2/13/2020.

Detention Pond A
Detention Pond B

Clue

Look where the grass has established itself:

  • In A, the land was cleared before the detention pond was completed.
  • In B, the detention pond was completed before the land was cleared.

And the Answer Is…

If you guessed that Pond A is in Montgomery County, you guessed correctly. Pond A is in Woodridge Village, just north of Sherwood Trails and Elm Grove. It is their S1 detention pond (first southern).

Pond B is in Harris County just north of Bush Intercontinental Airport and Mercer Botanic Gardens.

How You Can Tell

Montgomery County does not require developers to install detention ponds before they clearcut the whole development. So they sometimes come long AFTER clearcutting.

Also, even though Page 44 of Montgomery County’s Drainage Criteria Manual says that “slopes must be revegetated immediately after construction to minimize erosion,” no one apparently enforces the regulation. The sides of Pond A have gone without grass for about a year. See close up below.

Erosion on the sides of Pond A shown above, the Woodridge Village S1 detention pond.

All 268 acres of Woodridge Village have been clearcut for the better part of a year. Meanwhile Perry Homes and its engineering firm LJA are just now taking bids on additional detention ponds for the northern section. And the sides of Pond A still have yet to sprout grass.

Harris County Regs Differ

Note in the Pond B photo how the sides of the channel have been stabilized with grass before the developer has even finished clearing the land.

Harris County employs low-impact development procedures (LID). Harris County Stormwater Quality Management regulations discourage clearcutting giant sites like Woodridge Village all at once. See section 4.2.3.1, Stormwater Pollution Prevention (SWPPP) During Construction.

The text states, “The clearing, grubbing and scalping (mass clearing or grading) of excessively large areas of land at one time promotes erosion and sedimentation problems. On the areas where disturbance takes place the site designer should consider staging construction [emphasis added], temporary seeding and/or temporary mulching as a technique to reduce erosion. Staging construction involves stabilizing one part of the site before disturbing another [emphasis added].

Two Different Approaches

You would think that preventing erosion would be cheaper than cleaning it up. Why do a job once when you can do it twice? Right?

Close up of remediation work in Pond A, from a slightly different angle. Photo taken 2/13/2020.

Evidently, Perry Homes prefers it that way. Last Thursday, I spotted men digging out the pilot channel of Pond A and restoring slopes…again. This was at least the third or fourth time. No wonder those Perry Homes are so expensive.

Posted by Bob Rehak on 2/16/2020

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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.