TULSA WILL FLOOD AGAIN

ARKANSAS RIVER LEVEES: Tulsa’s Ticking Flood Bomb

By Mike Koster  Posted October 24, 2020

In the summer of 2019, Tulsa and other areas of Oklahoma along the Arkansas River suffered catastrophic flooding, as predicted by Tulsa Talks Climate, other environmental organizations, and many concerned citizens. Tulsa’s most decrepit levees leaked and eroded, requiring round-the-clock crews to shore them up during historic rains in the southern Midwest that drained into the Arkansas, forcing the Army Corps of Engineers to release huge amounts of waters from the Keystone Dam upriver from Tulsa. Waters subsided just short of topping the levees, which would have been a disaster of epic proportions. The Corps is now conducting a study of the levees, which we all hope will result in action. As of now:

Tulsa levees will not be able to hold back rising waters when there’s another flood (not if, but when)

(A version of the following was originally published by Bob Jackman on 2/5/2018 in the Oklahoma Observer)

Floodplain: an area of low-lying ground adjacent to a river, formed mainly of river sediments and subject to flooding.

“Since the 1970s, we have not built noncompliant homes in floodplains.”
–Tulsa City Councilor Anna America, quoted in a 2017 Government.com article

Here are some suppressed facts on a catastrophe-in-the-making: Tulsa’s long-neglected levees. City and federal officials have all but ignored the sorely needed rebuilding, and they have treated smart science and hydro-engineering like skunks at a picnic. Warning: Tulsa’s flood-bomb ticking grows louder and faster due to climate change’s increasingly volatile and extreme events.

THE 1986 FLOOD: Thirty-two years ago, from Sept. 28 to Oct. 3, 1986, the slow flowing Arkansas River, running 46 miles in and out of Tulsa County, abruptly changed. Down came 15-20 inches of rain from the stalled remnant of Hurricane Henry. Suddenly the shallow, wide river of sandbars became a rampaging flood, leaving $123 million in damages with thousands displaced. The river’s levee system—a safety net built in the 1940s to protect the West Tulsa refinery and industrial war effort plants—was broken along its entire 20 miles. Luckily, the levees mostly held in 1986, thanks to 125 volunteers’ non-stop sandbagging plus trucks and bulldozers. They prevented a major flood disaster at Sand Springs, closing a 30-foot-wide and 18-foot-deep levee breach.

But nothing has been done to make levees whole since 1986 and they have seriously weakened even more! Oklahoma heavy rain laden storm cells are often stalled remnants of Pacific or Gulf tropical hurricanes. They grow, then dump record rates of flooding waters, responsible for many of eastern Oklahoma’s most damaging rain storms. Today, the Tulsa County Levee District reports that Tulsa levees will not be able to contain or hold back high rising waters if there’s another Arkansas River flood—not even one that’s 60% smaller than in 1986.

The U.S. Army Corps of Engineers in 2014 reported Tulsa’s levee system is one of the highest-risk hazards in the country.

Moreover, experts estimate it would take eight to 10 years before replacement levees can be built in Tulsa County. This means from 1986 to the 2028 best-estimated completion date, 42 years would have transpired before anything was done to fix the levees after the record 1986 flood!  U.S. Sen. Bob Kerr, please come back! In 2016 Tulsa’s then-mayor Dewey Bartlett, with others, celebrated the 30th anniversary of the 1986 record flood by placing a sign showing the high water mark at the far south riverside area of Tulsa. The sign was removed shortly after by local developer selling city permitted lots and building new large homes on this swampy Arkansas River floodplain, where the sign had stood. As Pogo said, “We have met the enemy and he is us.”

According to the dictionary, a floodplain is an area of low-lying ground adjacent to a river, formed mainly of river sediments and subject to flooding. Hydrologists and geologists know the reality that “once a floodplain, always a floodplain,” and buying into FEMA’s National Flood Insurance Program [NFIP] will not change that. Someone should ask Tulsa, Sand Springs, Jenks and Bixby officials if their new riverside homes or businesses are flood-protected financially. Why? Because NFIP was bankrupt—$25 billion in the red—before Hurricane Harvey hit Houston. And with Texans asking the 2018 Congress for additional $125 billion for Houston’s damages and Florida asking $27 billion more for Irma’s damages, it begs the question: If big floods hit the Tulsa area, just how good is the floodplain property insurance policy?

The Arkansas River flows through Tulsa, Sand Springs, Jenks and Bixby, all in Tulsa County. Since 1986, numerous Tulsa county commissioners, city mayors, city council members, area U.S. congressmen, and the state’s U.S. senators have said, in effect, “We are really concerned about another Arkansas River flood and the levees issues.” But not one of them— including the currently elected—has really championed or demanded action to fix the levee system now.

The U.S. Army Corps of Engineers projects the damages from a 500-year flood would exceed $2.5 billion in Tulsa and Tulsa County—not to mention putting 10,000 people at risk. Civil engineers have said that failed levees contributed to the 2017 devastation in Houston and to New Orleans’ catastrophic and deadly flooding in 2005 caused by Hurricane Katrina.

Levees fail because of animal burrows, tree growth, culvert and piping penetrations, poor original design and construction, and settlement of sandy materials—all create zones of weakness for future breaching. What is needed immediately is federal and local funding to fix the Arkansas River levees, a comprehensive approach that also includes new hydrological-flow modeling with separate 200- and 500-plus-year models showing riverside property owners’ risk.

Also needed is an assessment of the Arkansas River’s water quality in Tulsa; why developers in Tulsa, Jenks and Bixby were granted residential and commercial permits in high-risk floodplains; and why the city of Tulsa has failed to submit or implement a Federal Hazard Mitigation Grant Program, which has federal dollars available to buy out flood-prone or derelict areas. Further, why has Tulsa failed to produce a Post-Disaster Arkansas River Flood Plans? And though Tulsa’s new mayor, G.T. Bynum, assured voters in 2016 that “Arkansas River waters are safe for swimming,” the city has failed to fulfill requests for such certification.

In Tulsa’s stretch of the Arkansas River floodplain, the 100-year flood standard would mean high waters swirling against 1940-era levees. A 100-year flood would represent only 65% of the record 1986 flood. A 500-year flood would be 1.6 times the 1986 flood, with six to eight feet of water over the tops of the nonfunctioning levees. Now, because of climate change, Oklahoma’s chief climatologist recently told Tulsans to expect more frequent mega-rain storms. Worth noting: The Dutch, considered the world’s geniuses when it comes to levee systems, factor in 10,000-year floods in their construction and maintenance processes.

What is happening along other major U.S. rivers? Along the Mississippi River’s 2,200 miles of levees, many are being assessed and repaired, factoring in climate change. By contrast, Tulsa’s Mayor Bynum moves forward on spending $127 million on Arkansas River recreational amenities, which many doubt could withstand a major flood. Bynum’s plan is to prioritize public recreation projects ahead of the river’s public safety projects. The city has contracts in place with alphabetical named engineering firms; Who are these guys and why aren’t they factoring in climate change? Human casualty risks are low on Bynum’s new scenic bridge, kayak canal and low water dams, but high on private properties and homes in the floodplain. Recently, the Tulsa World reported Bynum’s 16 goals for the city, but fixing levees was left out, despite almost daily warnings about climate change-inducing major floods! Look out Tulsa’s Brookside neighborhood.

Sadly, it seems, Oklahoma is the national epicenter of climate change deniers, at least when it comes to city, state and federally elected officials. The cost of re-engineering and rebuilding, higher and wider, Tulsa County’s 20 miles of levees is estimated at between $60 million and $90 million. Add the need for new levees to protect post-1986 Arkansas River floodplain development in Jenks, south Tulsa and Bixby and the estimated cost jumps another $150 million, not including land and property acquisition costs.

—Bob Jackman is a Tulsa-based petroleum geologist.

Further Reading:

Tulsa’s failing levee system

2017 Government.com article on Tulsa flooding.

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