Your two kidneys are bean-shaped organs in your upper abdomen. They regulate your bodily fluids and clean blood to remove toxins and wastes. Nearly 2,000 liters of blood passes though the kidneys each day. Each kidney has some one-million tiny filtration units, called nephrons. Nephrons have blood-filtering capillaries called glomerulus and renal tubules where urine is formed. This excess water and waste passes into the kidneys’ collecting ducts and then flows into the bladder.