A TEAM of experts from the U.S. Army Corps of Engineers will arrive next week to present at least five options for the CNMI government to consider to restore Saipan’s lagoon which has been “degrading” in recent years.
The area under consideration covers a 1.5-mile stretch of shoreline in western Saipan, from the Garapan fishing base to the Quartermaster Road intersection.
“Controlling and treating stormwater will help improve lagoon water quality and the overall aquatic ecosystem function by limiting contaminant and sediment flow into the lagoon,” the Army Corps said in a report to be presented to CNMI officials on June 27.
The Army Corps, however, said using a combination of retention basins and constructed wetlands will provide the “most comprehensive solution and allow for the most efficient use of available property.”
“This would be the first major restoration of its kind if the CNMI has the funding. There’s a possibility that it would cost more than a million,” according to Benny Pangelinan, coastal programs coordinator of the Coastal Resources Management.
Milton Yoshimoto, project manager of the Army Corps Honolulu district’s civil works branch, will head the visiting team.
It would be up to CRM to decide which among the proposed alternatives it would endorse to Gov. Juan N. Babauta for approval.
“CRM will recommend to the governor the most feasible and acceptable solution or alternative to restore our lagoon,” Pangelinan said in an interview.
While the study on the Saipan lagoon restoration was fully funded by the Army Corps, the implementation of the workplan is expected to be shouldered by the CNMI government.
The Army Corps said future urbanization of project watershed will increase stormwater runoff to the lagoon.
It added that the lack of comprehensive stormwater drainage system creates significant flooding during rainfall events.
‘Alternatives’
The Aquatic Ecosystem Restoration alternatives offered by the Army Corps are as follows: No action; collecting and conveying stormwater offshore; construction of retention/detention basins; make constructed wetlands; and the combined construction of retention/detention basins and wetlands.
Pangelinan said the collection and conveying of stormwater runoff may involve having a big and long pipe that will drain all runoff water from Saipan outside the reef.
The Army Corps’ power point presentation paper, a copy of which was obtained yesterday by Variety, ranked the last alternative for its “very high” positive effects to the lagoon environment, particularly on the lagoon water quality and flood control.
A preliminary study conducted by the Army Corps showed that Saipan lagoon waters that used to be clear in all but heaviest rainfalls are now typically discolored brown after every rainfall.
The study said that the previously white sand beach along Garapan is now tinged with the browns and grays of terrestrial sediments, thus needing cost-effective means of restoration.
