The answers are; droughts and floods.
The state of North Dakota spent money creating barriers and diversion canals. North Dakota was preparing for floods. The state of Washington spent money building desalination plants. Washington was preparing for droughts.
A drought is a natural occurrence and a period of below average rainfall in a particular region which lead to severe and longer water supply shortages. Droughts can have a negative impact on the ecosystem, agriculture and the local economy.
Flood is an overflow of water from a lake or other water bodies as a result of excessive rainfall or other input of water. Floods can have a negative influence on the community and it frequently destroys homes and businesses.