A local vendor has said a “controls issue” caused a shelter’s doors to lock during a tornado warning at Delaware State Park last weekend.
The incident left campers waiting outside up to 20 minutes for a park supervisor to unlock the $1 million steel-reinforced concrete shelter on the night of June 15. When a second tornado warning sounded that same night, the doors were already unlocked at the 75-foot-wide by 28-foot-high domed shelter designed to hold more than 850 people and withstand winds of more than 200 miles per hour. In addition, the shelter, the only one of its kind in an Ohio State Park, also worked properly a couple weeks previously when two successive tornado warnings had been issued for Delaware County.
While everyone was safe, the incident sent county and state officials scrambling to find the cause of the problem and prevent it from happening again.
Delaware-based 2K General Company, in a letter sent to the Ohio Department of Natural Resources on June 18, said the company sent staff on Monday to troubleshoot the shelter. ODNR owns the building, which was constructed last year, but officially unveiled in May.
2K General Project Manager Kirk Swinehart states in the letter that “the shelter locking system was designed to automatically unlock” in the event of loss of electrical power, or the activation of a tornado siren (Delaware State Park has two sirens). Engineers call this a “fail-safe” design feature.
“If either of these events occur, the shelter would fail-safe (unlock) and stay in that condition until park staff reset (locked) the facility,” the letter continues.
Swinehart wrote that during all previous tests and inspections, the system operated as designed. However, on Monday when the failure simulation “was left in place much longer,” it revealed “a controls issue that caused the doors to momentarily unlock, then after a longer period, the doors re-locked automatically. Once this controls issue was discovered and corrected by the contractor, the system worked as designed.”
As a result of the troubleshooting, 2K General said it will update the wiring diagram; and it also recommends “monthly verification through simulation testing that the doors in fact fail-safe to an unlocked condition.”
In a press conference on Monday, ODNR and Delaware County EMA officials said they were also working on contingency plans to have access to extra keys, yet minimizing the chance of the shelter being vandalized.