Chef Sam Hayward has won a James Beard award for his work at Fore Street, one of the best-known restaurants in Portland. But even he had the jitters Saturday during the opening night of Scales, the new restaurant on the refurbished Maine Wharf, located a stone’s throw across the water from the Casco Bay Lines ferry terminal.

It was, perhaps, the most anticipated – and secretive – local restaurant opening in years, and the largest project ever tackled in Portland by Hayward and his business partners, Dana Street and Victor Leon. Street and Leon also own Street & Co., a seafood restaurant on Wharf Street, and helped launch Standard Baking Co.

“I know from experience that a lot can go wrong in the initial stages, so we’re approaching it with a certain humility,” Hayward said as he relaxed for a moment Saturday night at a table for two by the bar, where a staff member was opening oysters from Pemaquid, Newcastle and New Brunswick.

Scales illustrates the difficulty of opening a restaurant in the age of social media. Restaurateurs typically walk a fine line between worry that no one will show up on opening night and anxiety about too many eager diners lining up at the door and overwhelming a staff that’s still trying to work out the kinks in the operation. Scales had three “soft” friends-and-family openings last week that were by invitation only, but the people who attended let the cat out of the bag, posting about their experiences immediately on Facebook and Twitter.

But even after those soft-opening “rehearsals” became public knowledge, Street said he would never tell anyone in the media when the restaurant was officially opening because he didn’t want too many customers too soon. Even the chef, Street proclaimed, wouldn’t know when the restaurant was opening “until I say so.”

Scales did have a few labor pains. The soft opening on Sunday of last week was “rough,” Hayward said, but Tuesday night things improved, and Thursday was even better.

So on Saturday, around 5:30 p.m., Hayward announced the opening night on his personal Facebook page. In less than an hour, the announcement had been “liked” more than 150 times, and by Sunday morning congratulatory comments were more than double that. “Congratulations! Break a sauce!” wrote award-winning Chicago chef Jason Vincent, who once worked in the open kitchen at Fore Street.

So much for a quiet opening.

As for the restaurant? The staff is young. The kitchen is big. The food is quintessential New England.

Hayward said he wanted a broad menu featuring familiar, traditional-but-elevated Maine coastal food, such as the cod filet seared in hazelnut brown butter that sends out an intoxicating aroma, and the seared scallops served with charred endive, celery root and blood sausage.

He also wants to keep plates simple, so that “when you order a plate of cod, you’re really experiencing the quality of the fish,” he said. “And that means that it’s not gussied up in some way that’s not intrinsically New England that covers up the flavor and the experience of the cod.”

Three kinds of seafood chowder are on the menu, along with hot and cold seafood appetizers, and a raw bar serving both fish and shellfish. The Jonah crab claws sold out opening night.

Even the cocktail menu features a whiff of the sea. The Maine Wharf is made with a local sake and gin infused with Maine sugar kelp and celery. It’s served straight up, with a piece of seaweed floating in it. The Loretta, a vodka-and-grapefruit concoction, is named, according to a server, after a harbor seal that hangs out by the pier.

Michael Burke, formerly in wine sales and co-owner of the (now closed) Una Kitchen Bar in Portland, created the wine list and serves as the general manager. Longtime Portlanders will recognize cook/restaurateur Johnny Robinson, the original owner of Hugo’s, working behind the bar.

Then there’s the huge open kitchen, a corps of line cooks and assistants led by chef Mike Smith and three sous chefs, a pastry chef and a pastry sous chef.

“We’re learning how to play a very big instrument,” Hayward said. “It’s a big kitchen with a lot of stations and a lot of people working at those stations. So the orchestration of the kitchen is a challenge. We’re slowly getting it down, but it’s a 140-seat restaurant and it’s probably going to be even bigger in the summertime when we get outdoor space, if the city will allow us to develop that space.”

The staff is making the restaurant’s own butter to serve with the Parker House rolls baked on site. A large investment in equipment means that bread can be baked fresh several times during a dinner service.

When he interviewed for the chef’s job, Smith reminded Hayward of himself when he was 32 years old and hungry. Hayward and Street had already sketched out a rough menu, but Hayward decided to step back and let Smith fill in the blanks – to give him the same opportunities he had asked for at the same age. One of Smith’s contributions is a light-as-air whipped beef butter appetizer, made with roasted, seasoned bone marrow and served with warm toast and radishes.

For now, Scales is open only for dinner, at 5:30 p.m. daily. Sometime later in the spring, lunch service will be added.

On Saturday night, John and Jolene Talty of Cape Elizabeth walked out of the restaurant just as a horn sounded and the final call for an evening ferry boomed from the next pier over. Jolene Talty carried the remains of her short ribs in a box. She said she loved the wood flooring and clean lines of the restaurant space. Her husband said he’d ordered the scallops and pronounced them “phenomenal.”

“They didn’t rush to open the place,” he said. “They’re not trying to pressure themselves too much. But they did a great job. Dana Street definitely pulled out all the stops for this particular restaurant.”