Update (noon): The release from Keystone Dam is 232,736 cubic feet per second as of noon, according to the Army Corps of Engineers' website.
Update 10:30 a.m.: The release from Keystone Dam is 221,830 cubic feet per second as of 10 a.m., according to the Army Corps of Engineers' website. Data is not available about the inflow to the lake, but the lake's elevation was 753.2 feet, less than a foot from the top of the flood pool and 30 feet above normal.
The National Weather Service in Tulsa increased the forecasted level of the Arkansas River from 21 feet to 23 feet, putting the river in major flood stage and only 2 feet shy of levels reached in October 1986.
Multiple street closings in the city of Tulsa near the Arkansas River are expected to close as waters rise. The rate of release at Keystone is set to increase to 250,000 cfs at noon. That release rate is expected through Sunday.
Levee officials will be on hand as the Army Corps of Engineers increases the rate of release to ensure levees can maintain the flow. Flood sirens will be activated every half-hour for six hours starting at 6 p.m.
Residents can find images showing how the 1986 flood affected Tulsa at cityoftulsa.org/rivermaps.
Tulsa-area officials are preparing for flooding equal to Tulsa’s 1986 flood of record but cautioned Wednesday night that they do not necessarily expect the waters to rise to that level.
Mayor G.T. Bynum said that because there are “just too many variables involved” in predicting water levels along the Arkansas River, the decision was made to “prepare for the worst, hope for the best.”
“This does not mean that we have any information, or necessarily a guarantee or expectation that we will get there,” Bynum said at a news conference at Tulsa Police headquarters. “We would much rather everyone in town know what they need to do to prepare for the worst flood in the history of our city and have it not be as bad and have that be a relief than constantly be trying to catch up with (water flow) rates that fluctuate so much.”
The flood of record occurred on Oct. 5, 1986, when the U.S. Army Corps of Engineers released 307,000 cubic feet of water per second from Keystone Dam. The release rate Wednesday had been expected to increase to 215,000, according to the Corps, but Wednesday night it was 207,000 cubic feet per second, according to the Corps’ website.
Dave Williams, chief of hydrology and hydraulic engineering section for the Tulsa District Corps, said it is possible the flow from Keystone Dam could be increased Thursday morning when the situation is reassessed.
The Tulsa Police Department began evacuating neighborhoods along the Arkansas River on Wednesday afternoon but did not identify the areas for fear of looting.
Tulsa Police Deputy Chief Jonathan Brooks is serving as the incident commander for the public safety response to the flooding. He said that when evacuating neighborhoods, police would activate their sirens and lights to identify themselves and make the evacuation announcement over loudspeakers.
“We will announce that this is an emergency broadcast. They will announce who they are and that they (residents) are in a potential high-risk area,” Brooks said.
The city has released a map that shows areas that flooded in 1986. City officials said residents in those areas along the Arkansas River should begin preparing for the possibility of similar flooding.
Joe Kralicek, director of Tulsa Area Emergency Management Agency, explained that the organization has two types of sirens — one for flooding and one for tornadoes.
“They are very different sounds,” he said. “Our tornado siren is a high tone, our flood siren is a high-low tone. We have samples of the tones at the city of Tulsa website.”
County Commissioner Karen Keith said officials are keeping a close eye on the nearly 21-mile-long levee system that runs from Sand Springs to west Tulsa.
“We are all hoping and praying that it will hold up,” Keith said. “The longer the water is on it — I think at this point we’re going to have 2 or 3 feet of water standing on the levee — the bigger problem we have long term.”
Keith said it has been helpful that the Corps has been gradually increasing the flow from Keystone Dam.
“That helps somewhat keeping the erosion down,” she said. “It is a very delicate balance that we’re doing here.”
Keith encouraged people to take photos of their homes and have their insurance policies available.
“All of those things are so important if you have to put your life back together again after this incident,” Keith said.
Bynum and Gov. Kevin Stitt surveyed the flooding Wednesday morning in a helicopter. Several city councilors were also flown over the flooding in a Tulsa Police Department helicopter.
Evacuations were requested Wednesday by officials in Bixby, Sand Springs and Okmulgee County.