At its Thursday board meeting, the SJRA will reconsider whether to seasonally lower Lake Conroe again this year. Last year, the board lowered the lake as a way to provide an additional buffer against flooding until flood mitigation projects could be put in place. As part of the motion it approved last year, the board said it would revisit the decision each year. That time is now.
Even though Lake Houston area dredging continues and additional gates for the Lake Houston Dam have not yet been funded, re-approval of the lowering this year is far from automatic. Rumor has it that the Lake Conroe Association may present a petition urging the board to keep the lake at its usual height.
Details of Original Plan
What exactly was the temporary, seasonal lake lowering proposal? SJRA General Manager Jace Houston spelled out the details for the public in Dockline Magazine last year. I pulled these figures from there.As a point of reference, the normal pool level of Lake Conroe is 201’ msl (mean feet above sea level).
During the Spring season – April 1 through May 31 – the SJRA voted to start lowering the lake gradually on April 1 until it reached a level of 200 msl, i.e., one foot below normal. This is the rainiest part of Spring.
Then starting on June 1, the SJRA would begin to capture flows to restore normal lake elevation for June and July.
For the Fall season – August 1 through September 30 – which includes the peak of hurricane season, the SJRA would again reduce the lake gradually. Their target: 200 msl by August 15. That’s when most local schools resume and the summer vacation season starts to tape off.
After August 15, SJRA would continue gradually lowering the level of Lake Conroe until it reached 199 feet msl or two feet below normal pool by August 31.
Starting October 1, SJRA would again begin to capture flows to restore normal lake elevation.
If the lake level has already dropped to the target elevation just due to evaporation, no additional releases would be made.
If a storm enters the forecast while seasonal releases are being made to lower the lake level, such releases would be stopped and the river allowed to drain out until rainfall is out of the forecast.
Purpose for Season Lowering
Jace Houston cited three reasons for seasonal lowering as opposed to pre-releasing water immediately before storms.
- Release of water from Lake Conroe prior to a storm would put flows into the San Jacinto River and Lake Houston potentially exacerbating flooding.
- Staff from the City of Houston, the Coastal Water Authority, and the Harris County Flood Control District have expressed their desire to not pre-fill the river and Lake Houston prior to a storm with water released from Lake Conroe.
- Lake Conroe is located in the upper basin where it makes sense to retain flood waters to the extent possible.
Success of Last Year’s Plan Needs to Be Repeated
The seasonal lowering started last Fall. While we didn’t have any repeats of the monster storms we experienced in 2015, 2016, and 2017, we were reminded by three back to back storms between December 7 last year and January 7 this year how vulnerable we still are to flooding. Minor rains produced out-of-bank floods that left low-lying Forest Cove and Kingwood areas underwater for a nearly a month.
Until dredging is complete, we still need the buffer that lowering Lake Conroe provides.
Speak at Board Meeting
Residents have an opportunity to speak out for and against the seasonal lowering this Thursday morning, Feb. 28, 2019. Speakers are limited to three minutes each. Business attire is recommended. To reserve time to speak you must sign in by 7:45. The meeting will be in the tall building at:
1577 Dam Site Road
Conroe, Texas 77304
Allow an hour and fifteen minutes to an hour and a half to get there in rush hour traffic.
Hope to see lots of Humble and Kingwood people there. This is very important until we get mitigation measures in place.
If You Can’t Come, But Still Want to Help
Consider sending ReduceFlooding.com some of your most dramatic shots from the flood. See the Submissions page. We need to show the SJRA board how dramatic the flooding really was here. There are new faces on the board this year.
Posted by Bob Rehak on February 26, 2019
546 Days after Hurricane Harvey