Problems at McCarren Pool Has a Neighborhood Worried A security guard watched swimmers in the McCarren Park pool on Tuesday. When McCarren Park Pool reopened in Brooklyn last week after 28 years, it was hailed as a grand civic achievement and, perhaps, a milestone for a new social dynamic in the city, one in which people of different racial, ethnic and class backgrounds could socialize - or at least pursue the same activity - together. A place where the children of hipster artists, attracted by the upscale restoration with its designer flourishes, would play Marco Polo with youngsters from public housing. As Jonathan Marvel, the project's architect, put it, "As architects, it is our goal to contribute spaces that inspire community involvement and face time with each other." But within days, that excitement has been replaced by apprehension. Two fights at the pool and a handful of arrests confirmed the fears of some residents that the giant pool, with a capacity of 1,500, might draw an unruly crowd to a neighborhood divided among older residents of Italian and Polish descent, gentrifying newcomers and Hispanic families. What should have been a simple kickoff to summer in New York City has turned fraught, with capacity crowds and racially charged debates and complaints that the city should have committed more resources to the opening, from sanitation to security. "I'm not happy and not because of the pool, but because of the fighting," said Tony Otero, 71, who has lived near the pool for 25 years. It's not good for the community, it's trouble. All kinds of kids are coming here. Hot weather and the pool's reopening generated so much interest that by Friday, a day after its opening, the place was reaching its capacity early in the day. With a line of hundreds snaking around the block on the weekend, the crowd outside grew restless. Nearby merchants complained that pool visitors tossed litter on the ground, tagged buildings with graffiti and relieved themselves in public. Inside the pool on Friday, teenagers scuffled with a lifeguard who had ordered them to stop doing back flips and the pool closed an hour early. On Monday, two police officers were injured by swimmers who also persisted in doing backflips. Three men were arrested and charged with assault in the second degree, inciting to riot, criminal nuisance and menacing. Meredith Chesney, owner of Mousey Brown beauty salon near the pool, said she came out Saturday morning to discover three new tags on her roll-down security gate. "I thought, "O.K., it's Brooklyn, it's not that surprising," " she said. But then, 30 minutes later, I went outside to water my plants and I found someone had defecated right in front of the salon. It's shocking. Still, Ms. Chesney did not fault the would-be pool users; she was holding city officials responsible for not thinking through the potential trouble. There are bathrooms inside McCarren Pool, on Lorimer Street, but she urged portable toilets for the line outside. "It's almost Machiavellian how our public administration thinks they can realize these grand ideals for giant public pools without real infrastructure, like bathrooms," she said. It's really setting the public up to fail. It's very disheartening. McCarren Pool, which holds a staggering 1,057,914 gallons of water, is one of the biggest in the city and has a complicated history. It opened along with 10 others in 1936 in the depths of the Depression with Works Progress Administration money, under the auspices of Mayor Fiorello H. La Guardia and the parks commissioner and master builder Robert Moses. After sliding into disrepair, McCarren was shuttered in 1984. While the other 1936 pools were all renovated, McCarren remained stubbornly closed, its reopening delayed not only by lack of money, but also by a debate over its future. Some preservationists lobbied for a full-scale restoration, while neighborhood activists demanded its demolition, in part to prevent outsiders from using it. Some of the blog posts and comments in recent days have echoed the racially tinged dialogue of the 1980s, with neighbors of the pool blaming teenagers from outside the community. In fact, two of the men arrested came from a public housing complex, the Marcy Houses, on the border of Williamsburg and Bedford-Stuyvesant. The other lives across the street from the pool. Additional reporting was contributed by Joseph Goldstein, Juliet Linderman and Eric Newcomer.