Rafiyqa Muhammad opened the gate to a garden in the Summit Terrace neighborhood of Harrisburg on a warm morning in July. It had finally stopped raining, and the trees hummed with the chatter of birds and bugs.

“We need the rain, but of course as the rain hits our streets and our pavements and all, it turns into something totally different,” Muhammad said. “I’m going to use the word toxic.”

Rain gardens like this one, a flower-lined plot about the size of four rowhomes on the corner of Bailey and Summit streets, help keep that water from surging directly into storm drains.