All have been linked to health problems in people. The origins of sediment contamination can be divided into point and nonpoint sources of pollution. Point source pollution comes from a specific, identifiable source such as a pipe. Nonpoint source pollution cannot be traced to a specific spot. Point sources include municipal sewage treatment plants, overflows from combined sanitary and storm sewers, stormwater discharges from municipal and industrial facilities, and waste discharges from industry.
Atmospheric deposition is another source of nonpoint pollution.