Shaquille Stewart as Ro, Jonathan Miot as Ricky, Ivana (Tai) Alexander as Regina and Eli El as Ray in Ally Theatre Company's "#poolparty.” (Teresa Castracane Photography)

When ace swimmer Roya takes to the water, she’s not just contending with fluid resistance. Speeding along in her lane, she is painfully conscious of how racism has shaped the history of American swimming. For instance, she thinks about black Americans who have drowned because they never learned to swim. Awareness of such tragedies so distresses Roya that she considers quitting her high school swim team. “I feel like I’m swimming for the dead. Or through them,” she says at one point. “Over them. I look down and I see them. On the bottom of the pool.”

Conjured by actress Lori Pitts, who plays Roya, the moment captures the anguish and urgency behind Jennifer Mendenhall’s thoughtful but strained play “#poolparty,” making its world premiere in a decently acted but stilted-looking Ally Theatre Company production. Performed at Joe’s Movement Emporium in Mount Rainier, the play is in part a response to the story of Raymond Bowlding Sr., a black Mount Rainier resident who took legal action against the all-white private pool that denied his children membership in 1974; his actions forced the pool to integrate. Beyond that particular case, “#poolparty” meditates more broadly on the overlap between race-related injustice and the annals of America’s swimming pools.

The first full-length play by area actress Mendenhall, “#poolparty” imagines a fictional version of the Bowlding family. After the death of Ray Waters Sr. (the appealing Keith Irby), his children Ray (Eli El), Ricky (Jonathan Miot), Regina (Ivana [Tai] Alexander) and Ro (Shaquille Stewart) attend a ceremony honoring him for having desegregated a local pool. Ray’s daughter Roya attends too, but with reluctance: Aware not only of racism-related drownings but of the incidents that gave rise to the Black Lives Matter movement, she feels that to celebrate the desegregation of a pool is to express undue optimism about America.

Roya’s speeches about swimming are interesting and poetic, and the play creates a touching portrait of the Waters family. But Mendenhall has jammed too much of her obviously extensive research into the script. At the ceremony, for instance, Regina plunges into a lecture on the history of American swimming pools. Such informational sequences, together with some bluntly interspersed family flashbacks, give the play an ungainly quality. The formality of the speeches-at-a-ceremony conceit doesn’t help.

The execution of the play also has its flaws. The actors’ vocal delivery and facial expressions are lively and convincing: Miot — who radiates Ricky’s jokester spirit — and El are particularly good. But director Angelisa Gillyard has not managed to make the scenes appear natural on the stage: The actors often stand stiffly, looking awkward, even if they do not sound it.

The design is apt enough. Most noticeably, Jimmy Stubbs devised the minimalist set, with its blue geometric shapes. Hope Villanueva masterminded the projections, which appear behind the performers. The projections often feature watery surfaces or tree branches — images that convey a naturalness this heartfelt, diligently researched play rarely achieves.

Lori Pitts as Roya Waters in Ally Theatre Company's "#poolparty.” (Teresa Castracane Photography)

#poolparty, by Jennifer Mendenhall. Directed by Angelisa Gillyard; costume design, Asia-Anansi McCallum; lighting, Alex Davis. 90 minutes. Tickets: $15-25. Through July 15 at Joe’s Movement Emporium, 3309 Bunker Hill Rd., Mount Rainier, Md.