Honolulu District | Civil Works Projects | CNMI DRAFT Post Disaster Watershed Plan March 2022

CNMI DRAFT Post Disaster Watershed Plan March 2022

Study Location
The Commonwealth of the Northern Mariana Islands (CNMI) is a U.S. commonwealth within the Mariana Archipelago in the western Pacific Ocean (see Figure ES-0-1. Map of CNMI). CNMI is comprised of 14 islands with a total land area just under 184 square miles. The geographic scope for this WA includes the islands of Saipan, Tinian, and Rota, where the majority of CNMI’s 47,000 residents reside and most of the economic activity occurs.

CNMI has a warm and humid tropical climate with minimal temperature variation throughout the year. The dry season occurs between the months of December through June and a wet and humid season occurs between July and November. Most of CNMI’s heavy rainfall, high winds, storm surge, and coastal flooding are brought by tropical storms. The typhoon season occurs July through January.

Study Purpose
Funding for this WA was provided in response to Super Typhoon Yutu, equivalent to a Category 5 hurricane, which struck CNMI in October 2018 and caused widespread damage throughout the islands. The storm resulted in two fatalities and over 100 injuries. There were maximum sustained winds of approximately 180 miles per hour and torrential rain, which led to flooding, power outages, significant damage or destruction to critical infrastructure and buildings, and significant environmental degradation. Super Typhoon Yutu is the strongest recorded typhoon to impact CNMI and the second strongest to strike the United States or its territories.

The intent of this WA is to provide recommendations both within and outside of USACE authorities that will help to rehabilitate and improve the resiliency of damaged infrastructure and natural resources, reducing risks to human life and property from future natural hazards. This WA assessed the drivers of social, life loss, economic, and environmental risks through engagement with the public and other Federal and CNMI agencies, subject matter expert consultation, and research with the most recent reports available.

Contact Information

CNMI’s draft Watershed Management Plan is available for public and agency review from March 1 - April 15, 2022 (45-day comment period).

For questions about the project, or to submit comments, email