OMAHA, Neb. (AP) — The U.S. Army Corps of Engineers says it has almost completed work to close three of the most serious levee breaches on the Missouri River in southwest Iowa.

Matthew Krajewski is readiness branch chief for the Corps’ Omaha district. Krajewski says four of about 40 breaches needed urgent attention after the flooding in March and May , and three of those should be closed Monday.

The Omaha World-Herald reports that the levees needing urgent repair were designed to protect Council Bluffs, Bartlett, Percival and Hamburg. The closure of those four breaches is expected to cost more than $34 million.

The other breaches aren’t as large and don’t put as much infrastructure or people at risk. Some of the breaches are allowing water to flow back into the river from flooded fields.