Water: Marine Debris
National Marine Debris Monitoring Program
The National Marine Debris Monitoring Program (NMDMP), conducted by Ocean Conservancy and funded by EPA, was designed to standardize marine debris data collection in the United States using a scientifically valid protocol to determine marine debris status and trends. The study analyzed marine debris from three specific sources: land-based, ocean-based, and general (marine debris that cannot be distinguished as a land-based or ocean-based source). The study was conducted over a five-year period between September 2001 and September 2006.During the five-year period, approximately 600 volunteers conducted the NMDMP surveys across the country. The surveys were conducted on 28-day intervals and covered a 500-meter stretch of beach at each study site. The volunteers collected and recorded the various marine debris items found on NMDMP data cards. Data cards were collected and processed by Ocean Conservancy and entered into the NMDMP database.
The results of the study indicated that there was no significant change in the total amount of marine debris monitored along the coasts of the United States over the five-year period. However, when the data were analyzed specifically by source, the study did show an increase in general source items. General source items included plastic bags, straps, and plastic bottles. The study indicated that land-based sources of marine debris accounted for 49% of the debris surveyed nationally, in comparison to 18% from ocean-based sources and 33% from general sources. The study also found plastic straws, plastic bottles, plastic bags, metal beverage cans, and balloons to be the most abundant types of marine debris littering our coasts.
EPA believes that monitoring is an important tool to address this pervasive pollution problem. NMDMP represents the first significant assessment of marine debris in the United States. NMDMP provides a scientific basis for developing future marine debris prevention efforts, including directly addressing sources of the debris.
For more information on the NMDMP please see the Final Program Report: Data Analysis and Summary (PDF) (74 pp, 5.9MB, About PDF).
Following the completion of the NMDMP, EPA developed a National Marine Debris Monitoring Program – Lessons Learned White Paper (PDF) (28 pp, 1008K, About PDF). The white paper identifies the strengths and weaknesses of the monitoring protocol, explains the best practices and lessons learned, and provides specific recommendations for developing future marine debris monitoring protocols.