Our first post-pandemic forum with research updates Vitacress Conservation Trust 2022 Chalk Stream Headwaters Forum - 25 November The annual Vitacress Conservation Trust (VCT) Chalk Stream Headwaters Forum took place on 25 November at Sparsholt College, Winchester,...
Restoration work – 25 April 2022 as recorded by Martin Burton
The owner of the Itchen Stoke Mill at Ovington has kept his water meadows operating for the last 50 years. Water is taken from the River Itchen and spread across the meadows via a network of channels located on ridges in the meadow. Irrigating the water meadows in this way serves to increase the rate of growth of the grass, especially during the winter periods when the relatively warm river water (around 100C) keeps the grass growing. When used as a central part of riverside farming before WW2 the farmers could put cattle and sheep on the pasture four-six weeks earlier than on non-meadow pasture.
Itchen Stoke Mill
River Itchen at Ovington
Traditional gated intake from the river
The water enters the water meadows via a gated intake on the river (called a hatch in local terminology). This gate is opened and closed by inserting a steel rod into a metal plate on the gate and levering it up or down.
The water is carried to the meadows via open channels, some of which are in a reasonable condition and others which need repair. The main issues are damage to the channel banks by cattle and gradual erosion of the banks and filling of the channel, thus reducing the carrying capacity.
The bank repair material is either imported chalk which compacts down very well or material excavated from the bed of the channel.
Main channel from the intake, in good condition
Lower section of the main channel needing excavation and raising of the banks
Previously (before 1940) the meadows were operated and maintained by a full-time labourer (termed a ditcher).
Nowadays it is not economic to have someone working full-time on the meadows so the owner requests the assistance of the Hampshire Conservation Volunteers (HCV) who spend two-three weekends each year helping with maintenance. The HCV team usually comprises some 10-12 volunteers. The work involves digging out the channels, raising and repairing the channel banks, compacting the embankment fill, and repairing the gates and control structures.
In some cases, the channel has been badly damaged and has breached when filled with water. This takes a lot more effort to repair!
Chalk fill material for the channel banks
Chalk fill material placed on the main channel embankment ready for compaction
Breached main channel, on both sides, about halfway along its length
There are offtake points along the main channel where water is diverted to the meadows. Here the water runs along a ridge and flows either side down to the drains which carry the water back to the river. This can look a bit messy if the channel on the ridge has not been correctly formed to give an even flow either side of the channel.
Sometimes the drains become waterlogged which leads to the growth of water iris which impede the flow even more. Cutting a channel through the iris speeds up the flow and drains the waterlogged area.
Turnout from the main channel into a side channel – the wooden posts and planks are used to make a diversion structure
Flooding of a meadow with the water on the ridge flowing either side to irrigate the grass
Before – drain obstructed by water iris
After – cleared pathway through the water iris allowing water to flow freely
Restoration work - 25 April 2022 as recorded by Martin Burton The owner of the Itchen Stoke Mill at Ovington has kept his water meadows operating for the last 50 years. Water is taken from the River Itchen and spread across the meadows via a network of channels...
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