The water in the bathroom is brown. I'd like to change rooms.
The water that came out of the tap in the bathroom was dirty. I'd like another room if I could.
この場合、次のような言い方ができますよ。
ーThe water in the bathroom is brown. I'd like to change rooms.
「お風呂場の水が茶色いので、部屋を替えたいです」
water in the bathroom「風呂場の水」
to change rooms「部屋を替える」
ーThe water that came out of the tap in the bathroom was dirty. I'd like another room if I could.
「お風呂場の蛇口から出てくる水が汚いので、できれば他の部屋がいいです」
to come out「出てくる」
tap「蛇口」
dirty「汚い」
ご参考まで！
カナダ 
