A splash dam was a temporary wooden dam used to raise the water level in streams to float logs downstream to sawmills. By impounding water and allowing it to be released on the log drive's schedule, these dams allowed many more logs to be brought to market than the natural flow of the stream allowed. Water releases from multiple splash dams on tributaries were also often combined to maximize the number of logs floated throughout a given watershed.

A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aquaculture, and navigability. Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions.