Lowering Lake Conroe Temporarily Could Be Blessing in Disguise for Lakefront Property Owners

The Lake Conroe Association, which fought the temporary lowering of Lake Conroe, may find that it’s a blessing in disguise.

The TCEQ decided to allow the San Jacinto River Authority and City of Houston to lower Lake Conroe for six weeks by up to two feet during the peak of hurricane season. The SJRA will lower the lake to 199 feet if evaporation does not already reduce it that much.

Lowering Lake Could Facilitate Repairs, Help Fight Invasive Species

This should reduce the risk of flooding for people on both sides of the dam between August 15 and September 30. It could also give lakefront property owners an opportunity to repair shallow docks, retaining walls and other waterfront property.

That’s what the property owners on Lakes LBJ and Austin did for six weeks while the Lower Colorado River Authority (LCRA) lowered those lakes in 2017 to facilitate dam repairs.

Image of hydrilla, an invasive species, courtesy of USGS.

The Lower Colorado River Authority also urged their residents to use the 2017 drawdown as an opportunity to curb the growth of nuisance aquatic vegetation, such as hydrilla and Eurasian watermilfoil.

The Lake Conroe Association may find that lowering Lake Conroe helps in its fight against invasive aquatic vegetation. Battling hydrilla has been one of the group’s top priorities for more than forty years.

Opening of Dredging Bids Expected Later Today

Temporarily lowering Lake Conroe will provide a buffer against flooding for downstream residents who are currently fighting excessive sedimentation left behind by Hurricane Harvey. The sediment is blocking drainage ditches and exacerbating flooding.

The U.S. Army Corps of Engineers is expected to open bids today on its Emergency West Fork Dredging Project. The Corps has postponed the bid opening twice already to give bidders more time to resolve questions relating to the complex project. The earlier dates were May 31 and June 12. I will let you know as soon as I hear something. Once approved, the project is projected to take approximately six months to complete.

Update on Tropical Wave as of 6 a.m., 6/18/18

As of this morning, the level of Lake Conroe is at 200.59 feet. The level of the San Jacinto river at US59 is currently close to 41 feet, which is about 1.5 below normal, thanks to the City of Houston’s decision to lower the level of Lake Houston in advance of the approaching storm.

Height of San Jacinto River at US 59 according to USGS stream gage data.

However, with the tropical wave expected to stream moisture in from the Gulf of Mexico most of this week, both of those levels should increase.

The morning weather report from Space City Weather indicate that counties in the northern part of the Houston region could see rainfall accumulations from 1.2 to 2.4 inches today. The five day outlook calls for higher accumulations. However, Jeff Lindner of Harris County Flood Control says, “Thus far bands/waves of showers … have not trained over one particular area long enough to cause any problems.”

Currently, Main Risk is From Street Flooding

“Overall the current forecasted amounts of rainfall are likely to be handled by the creeks and bayous over the area as long as the rainfall continues to exhibit enough breaks allowing systems to drain. Grounds will slowly saturate as the rainfall totals add up leading to greater amounts of run-off as the event continues. While rises on area creeks and bayous will be possible, the main threat will be street flooding especially in any areas of intense rainfall,” says Lindner.

He indicates, though, that the risk of flash flooding has increased to “moderate” for Tuesday and Wednesday.

Downstream Residents Grateful

Residents that I talk to downstream of the Lake Conroe Dam are grateful for the decision to lower Lake Conroe temporarily. Many are still traumatized by Hurricane Harvey and repairing their homes from the flood it caused. They appreciate Lake Conroe residents who supported the lowering. While it may be a short-term inconvenience, it will give the Corps time to clear the river. Hopefully, it will also give residents of Lake Conroe time to repair their docks and renew their fight against invasive plant species.

Posted on June 18, 2018
293 Days since Hurricane Harvey