Storm water starts rising in neighborhoods near Addicks and Barker dams

The ground elevations in Barker Reservoir area. The ground elevations in Barker Reservoir area. Photo: Harris County Photo: Harris County Image 1 of / 420 Caption Close Storm water starts rising in neighborhoods near Addicks and Barker dams 1 / 420 Back to Gallery

The U.S. Army Corps of Engineers began releasing water from the Addicks and Barker reservoirs early Monday morning, hours before officials planned to release rainfall from the two dams, according to the Harris County Flood Control District.

The flood control district reported almost an hour later that storm water has started rising in the neighborhoods adjacent to Addicks and Barker. Heavy rainfall forced reservoir officials to begin releasing water from the dams sooner than previously planned.

Col. Lars N. Zetterstrom with the U.S. Army Corps of Engineers had announced late Sunday afternoon that rising levels in the two reservoirs would force authorities to release water from both dams.

The rising tides within the dams are forcing the water to swell and spill upstream into neighboring communities that sit against the dams.

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Based on the corps data, the rising waters could place residents in low-lying homes in dangerous situations. He said the measures were necessary to prevent uncontrolled releases.

How Addicks, Barker dams are supposed to work Water flows downward into creeks and streams in Addicks and Barker watersheds, kept behind large earthen dams. The dams control flow into Buffalo Bayou, which keeps downtown Houston from flooding. Too much water on both sides, and the flow is impacted. That’s complicated by the Houston Ship Channel, which is actually pushing water into Buffalo Bayou backwards. This week rising pool levels in Barker Reservoir and Addicks Reservoir spilled over into adjacent subdivisions that sit against the dams, shown below. Map created by data reporter John D. Harden

Source: Harris County Flood Control District

"We will have to release water to reduce the risk flooding in the Houston metropolitan area," he said. "Until we realize the actual rise we can't predict how many homes would be impacted."

Several thousand homes sit in the voluntary evacuation zone. Homeowners near the reservoirs will likely have water seep into their homes prior to the release as the swell continues through the night.

Residents upstream of the dam will begin seeing street flooding first. Then low-lying homes could begin taking in water.

Both Addicks and Barker collect water from streams and rivers that flow through Harris and Fort Bend counties. The surge of water created by Tropical Storm Harvey has resulted in the dams filling up quickly to the point of failure if water isn't released.





Photo: Michael Ciaglo, Staff Park Ranger David Mackintosh enters the water control structure on...

The water released from the dam will flow into an already bulging Buffalo Bayou and then eventually drain into the Houston Ship Channel.

This could lead to additional damage to structures along the bayou. Officials have not issued a voluntary evacuation for people living along the bayou, but residents should be cautious.

Fort Bend County issued the evacuation for portions of the county later Sunday.

Each dam will be set to release about 4,000 cubic feet of water per second, about double what they release during normal operations, and they will stay open for several weeks, Zetterstrom said. But even that release won't be enough to ease the dam because water flowing in from northern Harris County and Fort Bend is greater than the water released.

Officials are hoping the dying storm system will provide some relief and allow for greater releases and the week progresses.

All roads around the dams will be closed prior to releases.

Zetterstrom said the water taken in by the dam from the storms is unparalleled and will exceed records set in 2015 and 2016.

He said weather models shows that water would begin rising 4 to 6 inches an hour by early Monday morning.

VITAL LINE OF DEFENSE: Addicks and Barker were built to protect the heart of the city by controlling the flow of water along Buffalo Bayou. Things haven't gone as planned. What's at stake is the safety of the nation's fourth-largest city. If the dams failed, half of Houston would be underwater. Under the worst scenario at Addicks, property damages could reach $22.7 billion and 6,928 people could die. Read our story on the dams here.