Pompano Beach rests on a thin skin of sand over porous limestone, with fresh water moving just beneath its yards and the canals that thread toward the ocean. Hoover Pumping Systems works where that hidden water meets the lawn, with the pumping systems that lift it up and push it out through the lines. It is quiet, mechanical work: the low hum of a motor starting on schedule, pressure building, a whole yard of sprinklers rising at once as if on a single breath. When the pumping side runs right, nobody thinks about it at all; they simply notice a lawn still lush deep into the dry spring and beds that never go thirsty. On a still evening beside the Cypress Creek canal, that soft murmur is the sound of a landscape being looked after.