Surface water includes rivers, lakes, and reservoirs.
Large scale water supplies tend to rely on surface water, this includes slightly less than half the population. Chlorination also tends to increase the acidity of water, and acid waters are more capable of dissolving lead. The age of the house and type of plumbing determines the lead concentration in tap water. The source of lead in newer homes with copper pipes is the solder used to join the pipe, the lead eventually leaches away with age. A number of studies have shown that if food is cooked in contaminated water, the food will uptake lead from the water, however, tea and coffee binds the lead thus lowering the lead concentration in these beverages.