The volunteers of PB: Zegerplas are going to measure, over a period of at least one year, the visibility (horizontal), temperature at various depths and vertical visibility every other week. Near the location where these measurements are being collected, we will observe the biological status of species encountered on dives. Using standard forms from other Project Baseline groups in the Netherlands will use SETL plates to measure growth of mussels/sponges and other species at regular intervals through the year. Our team is honored to work under the guidance of w well established team called PB: Haarlemmermeerse bosplas. The teams will work together to take measurements that align with “best practices” for data collection. A process developed and adopted by many Project Baseline teams in the Netherlands. As the project matures, the Zegerplas team will seek training by biologists to perform biological data collection with consistency and regularity.