I ventured to McCarren Park Pool on a Monday afternoon expecting to see a snaking 45-minute line and to prove to a dubious security guard that I was indeed wearing a bathing suit underneath my clothes. I had expected to be drenched in sweat by the time I reached the entrance, to be drained of energy and patience, and to finally behold the newly renovated Brooklyn bathhouse and one million gallons of cool, clear water, only to find myself incapable of enjoying any of it. Instead, I had one of the loveliest Monday afternoons I’ve had in a while.

It almost wasn't so. I had just missed a complete evacuation of the 37,950-foot pool, the result of an early afternoon "diaper accident." In one of the more benign episodes that have occurred since the grand reopening on June 28, the pool was vacated for 20 minutes for a quick cleaning. By the time I had arrived and breezed through security, McCarren Park Pool was a blissful, picture-perfect image of summer in New York City: parents teaching children how to swim; 20-somethings lounging on the stepped seating area; swimmers peacefully doing laps in a wing of the U-shaped basin; sprinklers misting onto the center stretch of pavement.

This might have been the image Rogers Marvel Architects had in mind when the firm clinched the commission – part of Mayor Bloomberg's PlaNYC initiative – and began ruminating on McCarren's glorious resurrection. In its heyday, the pool was an even bigger summertime attraction, with the capacity to hold 6,000 people at any given time (the new McCarren can only hold 1,500). It opened in the summer of 1936 in the sticky heat of Depression-era New York, as part of then-Parks Commissioner Robert Moses's plan to provide recreation and job relief to the browbeaten masses. At the height of activity, McCarren drew in as many as 50,000 New Yorkers a day.

But north Brooklyn changed over the decades. An increasing number of non-whites were moving into what was at one point a relatively homogenous neighborhood of white immigrant families. Tensions surfaced in the summer heat. Pillaged locker rooms and frequent brawls moved some community members to condemn McCarren as an unwelcome attraction for rowdy Brooklynites from the poorer "south side." The pool fell into disrepair. Finally, in the 1980s, New York City proposed the renovation of McCarren and the 10 other Robert Moses-era pools. A new debate came to light, as a proposal to shrink the pool and install year-round facilities met resistance from locals arguing for the preservation of the original structure. In 1984, McCarren closed its gates, and its renovation was put on hold indefinitely.

The closed pool sat like a ruin on the Greenpoint-Williamsburg border until the summer of 2007, when the site became the venue for a series of free concerts. That was the McCarren Park Pool I had first come to know, the romantic backdrop for weekly waterless “pool parties.” The site was fenced in with razor wire, the brick bathhouse was overgrown with weeds, and the hollow basin was coated in graffiti. I remember standing in the empty, dry crater, gawking at the monumental relics of a seemingly distant past. Little did I know that same year, the city had awarded Rogers Marvel Architects with the commission to restore McCarren into a fully functioning public pool.

When I returned to McCarren this week to assess its urban renaissance, I reveled in the newness of the architecture. It was a completely different place. The original bathhouse – which was at one point threatened with demolition – was gracefully restored to its classical form. Unhurried by staff and security, I walked calmly and deliberately through the arched entryway, taking in the new brickwork and the expanse of blue sky framed in the open-air atrium.

Just beyond the entrance, the circulation splits symmetrically into two standalone locker rooms, and I was kindly directed toward the women’s facilities to the right. Here, classicism immediately gives way to a lush, modern aesthetic: wood-slatted and slate brick partitions demarcate a thin, L-shaped space with walls of new locker units, minimalist wood benches, and parallel rows of showers. A hovering white roof lets in natural light through large, gill-like openings, adding a very deliberate sculptural flair to the design.

The pool area is fittingly simple. The available seating on the periphery was more than enough for the weekday afternoon crowd, and the pool itself seemed surprisingly expansive. From the water, the surrounding brick structures and gates appear so modest and unpronounced that they almost dissolve into the landscaping. Rising condos and other landmarks of the neighborhood become immediately visible, reminding swimmers that this summer oasis is indeed in the middle of bustling New York City.

When I asked a lifeguard if the scene changes over the weekends, he chuckled and told me, "This is nothing." It was admittedly difficult to imagine McCarren functioning smoothly at full capacity, a challenge that reared its ugly head over the past two weekends. The steady stream of news since the pool's reopening – grievances over winding lines and acts of violence and vandalism – point to the same fears that shuttered McCarren almost three decades ago, the affirmation that such a diverse cross-section of New Yorkers could never peacefully enjoy public space. Some people blame gentrification, and others blame poverty. Some criticize aspects of the design, citing the thoughtless lack of amenities for crowds waiting in line. Rumors of an entrance fee to the pool began circulating.

Throughout my visit, I too had my doubts about McCarren. The small locker rooms seemed a bit precious at times. The scant number of water fountains – and what pool is complete without water fountains ­– felt like a design afterthought. I could easily foresee overcrowded bathrooms and uncomfortably packed seating areas. However, what came through loud and clear in the design, but even more so in the staff present that day, was a genuine desire to make it all work. I went to McCarren expecting to confront overbearing security guards. I expected the lifeguards and staff to assume the worst in people by default. But everyone was there, rather, to assume the best. I could still hear a trace of excitement when an attendant answered my questions and pointed me in the right direction. I could feel the city wanting the pool to be a success, to be a source of pride. If McCarren is going to work, I thought, this is why.

An earlier version of this article did not include information on the restoration debate that led to the pool's closing in 1984. This has been corrected.