Traffic lined up early, and backed up for a while into West Yellowstone, as Yellowstone National Park reopened Wednesday/NPS

No guidebook exists for reopening Yellowstone National Park after cataclysmic flooding, but things ran smoothly as 10,000-12,000 returned to the park Wednesday for the first time since flood waters ravaged northern sections of the park nine days ago.

Yellowstone Superintdent Cam Sholly said he couldn't have anticipated a better reopening of the park, where fast thinking and collaboration with area businesses and other stakeholders led to a system by which license plate numbers were used to permit visitors into the park. Vehicles with plates with a final even number are allowed in on even days of the month, and those with odd numbers are allowed in on odd days.

"This business owner proposed, what I first I have to admit I thought was a crazy idea, this alternating license plate system," Sholly said Wednesday evening during a phone call. "What we were looking for was a way to cut the traffic in half, so we could have manageable traffic on the South Loop."

The plan worked, at least for Wednesday. If it fails, Sholly said, a reservation system of some sort will be devised, but for the first day back after flooding closed the park nine days ago, this approach worked.

"You go from zero visitors to trying to load the park in a couple hours in only three entrances, obviously, that's a recipe for a traffic jam," the superintendent said. "And so for the first couple hours we had substantial lines early on. But every, every every all three entrances were completely clear, or within very minimal backup of vehicles like 10 or 20 cars, by noon. Looking at the traffic counts, we cut them almost exactly in half, looking at normal. We had a less than a 1 percent non-compliance rate, where people had to be turned around. So that's 5,000 cars give or take that are in the park today on the south loop, I think 48 or 50 were turned around because of because they had the wrong plate."

And by and large the visitors were understanding of the situation, he said.

"I'm not saying everybody was completely happy. I mean, no one likes to stand in line that long, but a large number of people just happy to be back in the park, just thanked us for getting the park back open," Sholly said.

By and large those visitors who entered Yellowstone on Wednesday were happy/NPS

On Thursday the superintendent said staff would be ready to open the South, West, and East entrance gates earlier than Wednesday, when they opened at 8 a.m.

Meanwhile, recovery work continues to build steam in the northern half of Yellowstone, and it will take time for repairs. In the case of the north entrance road between Gardiner, Montana, and Mammoth Hot Springs, it could take three-five years, said Sholly. In the meantime, the old stagecoach road from Mammoth Hot Springs to Gardiner that dates to 1904 is being upgraded to temporarily handle traffic, he said.

"We've put over 5,000 tons of gravel on it in the last week. We diverted one of our main construction companies that was working on the project to redo the road between West Thumb and Old Faithful, the Federal Highways Administration redirected them on a different contract up here to help us improve the road," said Sholly. 

The work is to create a two-lane road that can handle traffic until a new north entrance road is built, the superintendent said. Damage assessments of the northeast entrance road from Tower Junction to Cooke City, Montana, also are underway, and the superintendent said engineers are optimistic they can come up with temporary solutions to allow for traffic to resume to some degree.

As far as lodging, the Mammoth Hotel complex and cabins will not reopen this year because the wastewater line that ran from Mammoth Hot Springs to Gardiner, under the Gardner River, was severed by the floods. A temporary solution is diverting the wastewater to protect the river, but it will be a while before that line can be replaced and the current diversion system can't handle more than day use, said Sholly. 

No decision has been made on whether the lodging at Tower will reopen this year. While the Canyon lodgings and campground, along with the Madison campground, were closed, Sholly said if the alternating license plate system continues to operate smoothly he'd look to reopen those facilities.

"I purposefully left Canyon lodges, Canyon campground, and Madison campground closed until we see how this system works, because not knowing exactly what day use was going to be, and I just didn't want to flood the south loop without taking a few precautions," he said. "So what we've decided is we're going to see how this first three or four days go and if we feel comfortable with the amount of traffic in this other loop and I'm gonna go ahead and let them open Canyon lodges, campground, and Madison."

Support from Washington has been great, said Sholly. The Interior Department and Federal Highways Administration have been providing as much aid as possible, he said. Fifteen engineers from FHA are working on the road problems, and Interior and the Transportation Department have helped package $50 million in emergency aid for the recovery work, said the superintendent.

"The [Interior] Secretary and then the [National Park Service] director was here this last weekend," Sholly pointed out. "And then the Federal Highways and DOT freed up a lot of money for us to kind of reconnect these communities as quickly as possible. It would not have happened without the support of the [Interior] department, the Park Service, and Federal Highways. The only reason on this northern end that we're accelerating as quickly as we are with these options is because of that support. I think it's really important to call that out because this has been a highly stressful period for a lot of people on multiple fronts and you know, it's just been absolute support all the way to the top and in both departments, so I really want to commend the leadership for that, I do."

That no one died or was injured during the flooding event is a testament to the professionalism of the rangers, the superintendent said.

"The teams have done a really great job. This is the longest nine days of my career. We've gone from last Monday, evacuating the entire park in mid-June in 24 hours, 36 hours, [it] was a major chore. Doing that without injuries or fatalities was incredible. The rangers in Yellowstone saved people's lives, I guarantee it, because we had no flood warning. And that Sunday night, they proactively, they saw some rock slides and the water levels, they proactively closed a bunch of sections of road that ended up collapsing," said Sholly. "And had they not done that, I guarantee you someone would have driven right off the edge of the river. And so I really applaud the proactive measures the law enforcement rangers took to go ahead and just shut down, in the middle of the night, shut down those sections of road they thought were dangerous. There were thousands of visitors in the park and thousands of visitors in Gardiner and I have no doubt someone would have been driving along in the rain in the dark and literally the road ends and it's 80 feet into the river."