HCFCD Begins Kingwood Diversion Ditch Repairs

Last week, while driving through Forest Cove, I noticed construction activity and Harris County Flood Control District signs at the Kingwood Diversion Ditch near Walnut Lane. The area downstream from the bridge has some of the worst erosion of any ditch in Kingwood.

Area Now Under Repair As It Looked in 2009

Kingwood Diversion Ditch in 2009. Looking south from Walnut Lane. Forest Cove on right.

Erosion was bad for years and only got worse during major storms in 2015, 2016, and 2017. Massive slabs of the banks broke off in chunks, threatening trails and adjacent homes.

Since the picture above in 2009, the ditch has eroded both down and outward to increase its conveyance as new subdivisions upstream scabbed off of Kingwood’s infrastructure.

Pictures of Work in Progress Today

Oh, what a difference a decade makes! Note the exposed storm drains in the pictures below that you cannot see in the picture above.

Looking south from Walnut Lane Bridge. Exposed, elevated and crushed storm drains due to erosion.

The erosion left storm drains elevated and exposed to the ravages of floodwaters. Some were crushed, causing water to back up into streets and drainage ditches during heavy rains.

The area that collapsed circa 2009 above is the same area shown under construction today.

The velocity of water through this ditch during floods has earned it the nickname “Kingwood Rapids” from white-water enthusiasts.

Storm drains left exposed and elevated as the ditch widened and deepened itself to accommodate upstream development such as Woodridge Forest.
HCFCD works to restore and stabilize banks, and repair damaged storm drains.
Crumpled drains being removed by excavator.

How the Diversion Ditch Got Its Name

The Kingwood Diversion Ditch got its name when Friendswood realized that Ben’s Branch could not hold all the water being brought to it by adjacent subdivisions.

So Friendswood literally built a ditch that diverts a portion of the water coming down Ben’s Branch from Montgomery County just above Northpark Drive.

The point of diversion. Believe it or not, that’s Ben’s Branch flowing from bottom to top. As Ben’s Branch squeezes down, it forces water into the diversion ditch, which splits off to the right, just south of the new St. Martha’s Catholic Church.
From there, the ditch goes under Northpark Drive, past Woodland Hills, and south to the river.

Luckily, Friendswood designed the bridges over the Diversion Ditch to accommodate expansion of the ditch. HCFCD is studying that possibility now as part of the Kingwood Area Drainage Analysis. Results of the study should be published this fall.

Posted by Bob Rehak on 6/5/2020

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