Six Sigma was supposed to eradicate the type of ordeal that all but ruined the Welch family’s picnic on the Fourth of July.

The family was forced to surrender their picnic shelter in Como Lake Park in Lancaster but took it in stride.

Hours later, they surrendered a second shelter — all because of bureaucratic mix-ups.

“It was a nightmare that I never want to see again,” said Angelo Welch of Cheektowaga, who had made the arrangements.

Erie County’s parks commissioner doesn’t like what happened, either.

“The good thing is, we’ve got a lot of activity in the parks,” Commissioner James Hornung said. “The bad thing is, we’ve got these errors I just can’t tolerate.”

Just months after County Executive Chris Collins took office, his staff last year set out to streamline the county’s picnic-shelter reservation system. They applied the Lean Six Sigma method — Collins’ beloved efficiency doctrine — to make the process easier for both the public and the parks staff.

This is the first full summer that the new system has been in use. The Independence Day episode at Como Lake Park, and a few others like it this year, illustrate that it remains a work in progress.

“It’s going to take some time for us to get the kinks out,” Hornung said.

Welch had paid $60 to rent Shelter 51 in Como Park. But when he and his family arrived with the hot dogs, grills, bags of charcoal and cases of soda, they found another family claiming the spot.

At one time, it wasn’t uncommon for people to claim picnic shelters without paying. But this time the parks staff — using a newer computer system, Hornung said — had mistakenly issued two permits for the same shelter.

Welch needed the matter cleared up promptly because dozens of relatives were expected, some coming from as far as Gary, Ind., and Nova Scotia, he said.

Hornung, who was at the park, suggested the Welch gathering be moved to Shelter 54. His printout showed that someone had tried to reserve it but had not paid, so Shelter 54 was available.

The Welches set up their stereo speakers and balloons. Out came the meats and salads. Dinner was set for 3 p. m., to leave enough time to linger afterward and still be home to see Cheektowaga’s fireworks display.

Soon, another family showed up to claim Shelter 54. They, too, had a valid permit.

While Hornung’s printout had indicated the family had not paid, he learned that someone else in the party, with a different name, had indeed paid in advance. They could rightly claim Shelter 54.

“We are arguing with them. They are arguing with us,” Welch recalled.

Lancaster police officers and Erie County sheriff’s deputies arrived as Hornung tried to mediate.

With both families refusing to budge, someone suggested they would then have to share the shelter.

“I said no. We will just move again,” Welch said. “And that’s what we ended up doing.”

Hornung, to express his appreciation, said he will give the family whatever park accommodations they choose for their next gathering, at no charge.

Welch said he will accept.

“We didn’t eat dinner until it almost got dark. We lost charcoal. It was just terrible,” Welch said.

And, he said, they missed Cheektowaga’s fireworks.