Tony Pait

2016

2017

Sedimentation has been identified as a high threat to coral reefs in the Manell-Geus Conservation Action Plan, and nutrients are highlighted in the Manell-Geus Habitat Blueprint. Jurisdictional managers have highlighted the area as being impacted by LBSP. In addition, the Achang Reef Flat Marine Preserve is part of the Guam Long-Term Coral Reef Monitoring Program, a CRCP-funded project. Working closely with local partners, we would assess turbidity, suspended sediment concentration, nutrient dynamics, flow, and chemical contaminants in two rivers in the Manell watershed that drain to the Achang Preserve in Cocos Lagoon, for one year. Candidate rivers in the Manell watershed include the Ajayan and the Liyog rivers. Turbidity loggers would be installed for unattended monitoring of turbidity, especially important when water flow in the rivers, for example after a storm, makes it too dangerous for personnel to be on or in the water. A hand-held turbidity meter would be used to check on the accuracy of the turbidity loggers, and to possibly assess turbidity in upstream areas. Water samples would be collected weekly or monthly by partners to assess suspended sediments (SSC) and nutrient inputs. Through this work estimates of sediment delivery from the rivers could be made. Partners would be fully involved in the design of the project, particularly in the identification of sampling sites, to ensure that the results would provide the critical information needed by managers. A former graduate student from the University of Guam would do the collection of water samples for turbidity, SSC, and the nutrient analysis, and also do a one-time collection of sediment samples for the analysis of chemical contaminants. There are great opportunities to link with other projects and activities in the area. As mentioned, a similar project has already been conducted in the Geus watershed by the University of Guam. Because the former graduate student who would do the work for the Manell project was also on the team that assessed the Geus watershed, the techniques used and the data collected from the Manell watershed would be directly comparable to the data from the Geus watershed. We are working closely with the NOAA CRCP Guam Coral Management Liaison and Coastal Specialist, and the NMFS Pacific Islands Regional Office Habitat Conservation Division scientist in the design of the project. Both are currently working on projects within the Manell watershed to plant vegetation to reduce erosion. The current project would serve not only as a baseline, but as restoration efforts progress in the Manell watershed, the data would be used to measure the effects of these restoration activities. For this project, we are also working with the Guam Environmental Protection Agency (GEPA) and the Guam Department of Agriculture, Division of Aquatic and Wildlife Resources (DAWR), in the design of the project, both are doing work in the Manell watershed, and also the University of Guam Marine Laboratory who is working on the Guam Long-Term Coral Reef Monitoring Program in the adjacent reef areas. The field scientist for this project would also have access to lab facilities at Guam EPA.

This project would supply information needed by resource managers and scientists on turbidity, SSC and sediment delivery, along with nutrient loading to the Achang Preserve, which are likely degrading water quality and impacting coral resources in the area. The monthly monitoring of both turbidity and nutrients would provide a baseline of conditions, and would also be used to assess how these stressors may vary during the course of the year, particularly during storms and even typhoons. In addition, the baseline information developed (e.g., turbidity and nutrients) would be used to assess the benefits of restoration activities in the watershed. Chemical contaminants would be analyzed one time in sediments from the rivers, providing information on whether the rivers which drain to Cocos Lagoon in the area of the Achang Preserve, may be sources of some of the chemical contaminants that have been observed in Cocos Lagoon.

• Guam

• Manell-Geus Watershed

Land-based Sources of Pollution (LBSP)

Closed

Funding Ended

https://www.coris.noaa.gov/search/rest/find/document?searchText=projectNumber%3A31084%20OR%20projectTitle%3A"Measurement%20of%20Turbidity%20and%20Nutrients%20in%20Two%20Rivers%20that%20Drain%20to%20the%20Achang%20Reef%20Flat%20from%20Manell%20Watershed%2C%20Guam"&start=1&max=10&f=searchPage