River Medina and Merstone Stream

Medina

The name Medina is derived from the Saxon name Medene meaning Middle River. The Medina rises as chalk springs from St Catherine’s Down on the south side of the Island. It is 17km long with a catchment area of 71 sq km, and flows due north.It flows through Cridmore Bog SSSI which comprises of extensive areas of marshy grassland interspersed with areas of species rich flush, valley bog and drainage ditches, on deep acid peat on the flat valley bottom. Collectively, these represent one of the largest remaining areas of wet acid peatland habitat on the IOW and contain a number of plant species now rare on the island.

It collects the Merstone Stream at Blackwater. The Merstone Stream flows from south of Rookley.

At Newport it has been heavily modified for flood defence purposes and also for historic industrial uses such as milling.

It has a linear estuary enclosed by a low valley with plenty of development and little marginal vegetation. It is tidal as far as Newport. Alverstone Stream and Dodnor Creek join the Medina in the estuary.

There are two partnerships that seek to enhance the Medina. Newport Rivers Group focuses on the watercourse as it flows through the Medina, whilst the Isle of Wight Estuaries Project have developed management plans and projects for the estuary. Projects include Medina Restoration Project, Medina Houseboats, Birchmore Pond, Riverfest and Pan Mill Meadows. In addition, Medina River and Merstone Stream are visited by our Himalayan Balsam Pulling volunteers.

The technical bits

The Catchment Data Explorer is an Environment Agency tool which helps you explore and download information about the water environment. It supports and builds upon the data in their river basin management plans. Read about the Medina and Merstone Stream here.

The Medina is currently classed as ‘Moderate’ quality within the Water Framework Directive. This means it is failing, and the aim is to improve. The objective set are ‘Moderate’ by 2021, and ‘Good’ by 2027. It is a heavily modified waterbody (HMWB) and has naturally occurring iron, which doesn’t help. Invasive non-native species and siltation also contribute to its challenges. Click for a fuller explanation.

The Medina Estuary is also classed as ‘Moderate’. There are a myriad of reasons for this. Click for a full explanation. However the objective is for ‘Good’ status by 2027. The Catchment Data Explorer gives full technical details for the estuary here.