About a week after the city closed down bars and restaurant dining rooms, Nomadic Beerworks ran out of 32-ounce crowlers — oversized cans that can be filled quickly with beer behind the bar — even though the South Austin brewery had stocked up three times the usual amount in anticipation of the since-canceled South by Southwest.

Since then, the two co-founders — brothers who had turned a high-ceilinged warehouse into a homey taproom last year — have had to get creative sourcing the aluminum vessels that have become essential to their business. Another local brewpub owner lent his extras to Dan and Bryce Tyranski. Then they were able to ship gold-colored crowlers from Denver. They bought out SoCo Homebrew’s selection of growlers, or large glass jugs, just in case. And now they are using a mix of 19-ounce, 25.3-ounce and 32-ounce crowlers.

The equivalent of a 750-milliliter bottle, the stubby 25.3-ounce crowlers are an odd size as far as beer cans go, like the long 19-ounce alternatives, but they’re one of just a few options left. Able only to sell beer to go amid the coronavirus pandemic, craft brewers are relying on the cans for their survival, even as much bigger competitors, such as Miller-Coors, are scooping up the metal packaging in great quantities for themselves.

Canning companies such as American Canning — which on Friday supplied Nomadic with a rationed number of the new cans — have become the mostly out-of-sight saviors of an entire industry, at least as much as they can be when brewery revenue has shriveled to roughly a quarter of what it used to be. American Canning and Armadillo Mobile Canning, both Austin-based, have seen their businesses boom of late.

American Canning CEO David Racino said orders for cans and crowlers "doubled pretty much overnight" in late March. The company, which works with about 3,000 craft beverage producers in the U.S., added a little more than 270 clients at the end of last month and has urged many of them to turn to unconventional packaging sizes, such as those 19- and 25.3-ounce crowlers, as inventory continually depletes.

Though much smaller in scope, Armadillo Mobile Canning has also seen business double since bars and brewery taprooms were shut down. Co-founder Adam Doss and his handful of employees take their two canning lines to two brewery clients a day, six days a week, up from one client a weekday on each line. (Like American, Armadillo supplies stand-alone cans to clients, who might have had enough capital to buy their own canning lines.)

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Despite the revenue gains, Doss is taking it day by day. He knows the future of his company is tied to the survival of his clients, and he’s worried many breweries won’t be able to last long serving only beer to go.

"There's just no way they're going to generate the revenue selling cans to go versus having butts in seats" at their taprooms, he said. "You capture 100% of the margin pouring straight from the tap, versus a can, when you have to buy your cans, your labels, a guy like me coming out to package them. It's already a margins-slim proposition for some of my clients. I've had some of them over the years tell me they lose money from canning their beer, but they keep doing it for market exposure."

For now, these cans are all they’ve got. Beer makers that have a wide distribution footprint, such as Real Ale Brewing, Austin Beerworks and Live Oak Brewing, might better be able to weather the loss of draft sales at taprooms, bars and restaurants because their products are also available in stores.

Then there are breweries like Nomadic that have centered their business model on the taproom, with little to no distribution to the marketplace. Often, the only way beer leaves their doors, pre-pandemic and now, is via crowler. (A fairly recent invention, the crowler is essentially a cross between the can and growler — filling with beer straight from the tap.)

A little more than a month ago, throwing all their focus into a taproom seemed like a sure-fire way for these breweries to counter increasingly stiff competition on bar and retail shelves. Now it’s left them especially vulnerable.

"We're easily down 50 to 60 percent in terms of volume" of beer sold, Nomadic co-owner Dan Tyranski said. "It definitely hurts, no doubt about it, but we’re thankful we've been able to hold onto staff. We haven't let anyone go or reduced their hours. We’ve been able to break even through all of this. We know that is really the best-case scenario."

Nomadic is one of the lucky ones. Texas breweries saw their revenue plummet an average of 71% as a result of mass closures during the pandemic, according to the Texas Craft Brewers Guild. Additionally, 63% of Texas breweries have had to lay off or furlough their employees. The numbers are similarly dire on a national scale, according to data from the Brewers Association, with most U.S. breweries seeing drops in sales "in excess of 70%." Nationwide, 66% of brewery workers have been laid off.

And there’s been at least one local casualty: On Thursday, North by Northwest Restaurant & Brewery owner Davis Tucker announced his 20-year-old brewpub’s permanent closure, citing the pandemic as the cause.

In Austin, brewery employees who remain take turns staffing a table at the front of their taprooms, where they can hand off crowlers, six-packs of 12-ounce cans or four-packs of 16-ounce cans to curbside customers. (Growler fills have become popular anew, depending on the availability of those other options.) Doss — who also has a shortage of workers because of voluntary furlough — has had to help staff the canning lines again and sees many of these quick transactions while packaging his clients’ brews. These include Oddwood Ales and Jester King Brewery.

"I think curbside sales have exceeded my clients’ expectations, although they pale in comparison to what these breweries would make in their taprooms, especially on a slamming Friday or Saturday night," he said.

Racino works extra hours, too. Only eight employees are on the massive American Canning production floor on a daily basis, filling orders as quickly as they can. Racino said he would hire more folks to help them but doesn’t want to risk accidentally exposing them to the virus by introducing new people, so they all make do. They are careful with sanitation practices and social distancing measures there, as well as at the breweries, like the ABGB and St. Elmo, where they’ve set up mobile canning operations.

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American and Armadillo, founded in 2013 and 2014, respectively, act as the middlemen between the large corporations that make aluminum cans — namely, Ball and Crown — and the craft breweries too small to order directly from them. A minimum order requirement from Ball, for example, would be an 18-wheeler’s worth of cans. The craft canning companies take that truckload and divvy up the supply by the pallet, which can hold up to 60 cases of beer.

But even the middlemen might have trouble getting what their clients need in this time of unprecedented demand.

For one thing, the Ball Corp. has the exclusive rights to make crowlers and does so only about once a quarter. American was able to get another shipment in this month but doesn’t expect it to last, with shortages likely in May and June. Racino has told clients to buy conversion kits to run different sizes on their crowler machines, from 16-ounce tallboys to the stubby-looking 25.3-ounce cans. Orders for the tallboys have gone up 80%.

"We’ve heard from some of them that (using the alternative can sizes) has literally saved their business," he said.

Even these, however, might become scarce. The pandemic has created "a disturbance in the supply chain," and with large producers such as Miller-Coors and Anheuser-Busch over-ordering cans to make sure they don’t run out, Doss has begun having trouble sourcing 16-ounce sizes in particular, he said. He recently ordered from a supplier in New Jersey, swallowing the cost of freight; in normal times, he can get cans from Conroe, much closer to home.

Brewers tend to be crafty folks. The Nomadic team — which went from selling about 60 to 75 crowlers per week to closer to 600 — was able to find 16-ounce cans on its own. The Tyranskis plan soon to offer four-packs of Nomadic’s Peak Season Juicy Tropical IPA, easily the brewery’s most popular beer. It’ll be the first can release for the almost 1-year-old spot and might not be the last.

"We're prepared (to have a beer-to-go model) till July if we have to," Dan Tyranski said. "But even moving past that, we've had discussions that this could very well change overall public sentiment toward public gathering, and the to-go size of our business might become a larger piece of the puzzle than it used to be. That would be a huge bummer, because we want to be a community gathering place for people to share a pint together.

"Honestly, there's no rule book for how to handle any of this. But people have been hanging in there. We’re doing what we have to."