Medina Estuary Surveys

We are involved with monitoring studies in the valley, including the recording of changes in the estuary.  We collect water samples on a regular basis and measure the salinity, temperature and use a Secchi disc to measure the turbidity.

Estuaries are very dynamic ecosystems and the Medina estuary exhibits both temporal and spatial changes. Depending on the conditions, stratification is sometimes exhibited.

The estuary is a Site of Special Scientific Interest (SSSI), and has International and European designations to protect the birds, especially during the Winter months.

Estuary Monitoring

The source of the River Medina is at Chale, in the south of the Island, and flows north to Newport, where it becomes tidal. The Medina Valley Centre is situated on the west bank of the estuary, 2 km from Newport. We have been monitoring the estuary since 1993, taking water samples and keeping records of the temperature, salinity and turbidity. Water samples and measurements are taken at or near to high tide from the end of the pontoon, where there is a tide gauge levelled to Chart Datum. Samples from the bottom of the estuary are obtained using a Cassella bottle and turbidity determined with a Secchi Disc. Water temperature is measured using a thermometer and salinity determined using a hydrometer and standard conversion tables.


For more information, including graphs representing the data we have collected, see our resource section on the Medina Estuary.