The traveling restrictions during the Covid-19 pandemic in 2020 and 2021 created a unique possibilityto measure water quality parameters along the coasts of the Dutch Caribbean Islands with minimisedanthropogenic pressure resulting from tourism. Such a baseline dataset could serve as a reference forfuture measurements of the monitoring parameters during periods without traveling restrictions,allowing the determination of the impact of the presence of tourists on the local water quality.Rijkswaterstaat contracted STINAPA Bonaire and the Caribbean Netherlands Science Institute (CNSI)to collect water samples along the coasts of Bonaire (STINAPA), and Saba and St. Eustatius (CNSI) inthe period October – December 2020. The samples were stored frozen until transport to theNetherlands where they were analysed by the NIOZ for nitrogen, phosphorous, and total organiccarbon. Wageningen Marine Research combined the results in the current report and formulatedrecommendations for future monitoring of coastal water quality at the Dutch Caribbean Islands.Although a wide range of samples was collected, especially in Bonaire and St. Eustatius, the number ofsamples per site was too low to obtain statistical power in the observations.Nonetheless, the first insights were achieved as follows:- The Bonaire locations generally showed lower nitrogen and phosphate concentrations in 2020than during a sampling campaign in 2012/13.- In water samples collected at St Eustatius the inorganic nutrient concentrations ranged fromlow impacted at positions more remote from the shore to high affected at specific shallowpositions.- At Saba no evident indications were found for negatively affected water quality. However, thedataset was minimal and covered only a small part of the coastline.- The available dataset suggests that the NH4-DIN ratio could be a good indicator of a disturbednutrient balance in the coastal water.And following future directions are recommended:- Extending the dataset in the future with more time points and additional analyses ...