The state Department of Transportation has won the go-ahead to close a portion of Moanalua Stream as part of its effort to clear the homeless from the Nimitz H-1 viaduct area.

The Board of Land and Natural Resources voted unanimously Friday to grant the DOT’s request.

Transportation officials said cleanup of the area under and near the viaduct will take place between Oct. 23 and Nov. 17, the same time frame as the stream closure. The office of state homeless coordinator Scott Morishige, the Department of Public Safety and contracted service organizations will begin notifying the roughly 180 people camped in the area and provide them outreach beginning Monday, DOT officials said.

The area to be cleared runs from Moanalua Bridge to the viaduct offramp and Kamehameha Highway-­Nimitz Highway. No lane closures are planned, transportation officials said.

Under the plan, people will not be allowed on the water to re-enter the viaduct area during cleanup operations. Signs will be posted.

The growing encampment is posing health and safety risks to the campers themselves as well as the surrounding community, a Department of Land and Natural Resources staff report said.

Among the lingering problems have been the theft of copper and electric wires in the area, which has darkened the streetlamps along that section of the H-1 freeway; repeated fires that have the potential to burn out of control; and complaints of thefts and break-ins by surrounding businesses, the staff report said.

Closing the stream and adjoining waterways will help deter people from camping along or near them, the DLNR report said. During heavy rain that caused flooding last year, debris from area homeless camps floated out onto both Moanalua and Kalihi streams. The debris included a houseboat and mounds of trash. Bacterial levels at Keehi Lagoon were elevated, a situation that forced health officials to close the lagoon.

“All of the people in the viaduct area will be encouraged to seek shelter and services, although past experience indicates that many will seek alternative campsites or try to return to the viaduct,” the report said.

The cleanup effort along the viaduct area actually began in July. Through regular outreach and trespassing enforcement since then, 62 individuals have been placed in supportive housing, DOT officials said.

The state is also hoping the cleanup will help ensure safety in the new Kahauiki Village on the makai side of Nimitz Highway.

DOT officials said that the area under the viaduct, when cleaned, will be fenced off and then used for storage by contractors constructing the city’s 20-mile rail line, which will be running past the area. A 24-hour security monitoring system will be installed.

Funding for cleanup operations includes $2 million from the state Legislature and $2 million in matching funds from the DOT.

HTM Contractors has the contract to clear the area and to sort, haul and store items that are left behind by campers, transportation officials said.

Property that’s not authorized to be left unattended for 24 hours or more will be considered abandoned. Those items will be retrieved and stored for a minimum of 30 days.