"Okay," I said, through the door. "Listen to me. Wrap up in your robe. Get decent and unlock the door and get on your knees next to the tub with your head over it, like you're washing your hair in the sink at Grandma's. I'm getting water. I'll be back in thirty seconds. Don't touch it with your hands. Keep your eyes shut tight."
"There's no water."
"There's always water," I said, and ran.
There is always water in a house, even when there isn't. There's the tank on the back of every toilet, two or three gallons apiece, clean, straight from the line, nothing in it but a flapper and a float. There's the water heater, forty or fifty gallons sitting in a steel tank with a brass drain valve at the bottom, the one every homeowner is supposed to flush once a year and almost nobody does. There's whatever's in the refrigerator. I knew all of it the way you know your own phone number, because I spent nineteen years estimating commercial roofs and the first thing every building engineer ever taught me was where the water was hiding.
I grabbed the stockpot off the rack in the kitchen, the big one we used for corn, and the plastic pitcher, and I went down the basement stairs two at a time to the mechanical room. The water heater was a fifty-gallon gas unit, maybe six years old. I didn't have a hose for the drain valve and I didn't have time to find one. I set the stockpot on the floor under the valve, turned the little brass handle with a screwdriver, and nothing happened, and then I remembered that a tank with no pressure behind it holds its water like a thumb over a straw, so I ran up to the half bath, opened the hot tap on the sink to let the air in, ran back down, and the drain valve coughed and gave me a thick, rusty spurt and then a steady stream, warm, nearly hot. While the pot filled I noticed, without really noticing, the red-painted riser on the wall beside the heater, the one the inspector had pointed out to us at the walkthrough, with its round gauge and its little brass tag. The needle on the gauge sat on zero. I filed that away for later, the way you file things away in an emergency, without opening the drawer.
I came back up the stairs with the pot sloshing against my legs, filled the pitcher halfway from it, and topped the pitcher off with cold from the toilet tank in the hall bath, because the water out of the heater was too hot for a scalp that was already burning. I tested it on the inside of my wrist the way Esme and I used to test bottles when Pia was a baby. Lukewarm. Not hot. Not cold enough to shock her.
The bathroom door was unlocked now. Pia was on her knees in her old blue terrycloth robe, the one with the hood she never used, bent over the side of the tub with her forehead nearly touching the far edge, her hands balled into fists in front of her face. Her hair was a gluey, pale yellow mass at the back of her head, the color of a manila envelope, with streaks of her own dark brown still showing where she'd started rinsing. Even from the doorway I could smell it, that sharp, sweetish ammonia smell, like a swimming pool and a chemistry lab had gotten married.