Coots, cormorants, kingfishers and swans are thriving
Just over two years after the London Olympics, the wetland planting along the rivers running through the Olympic Park looks as if it has always been there. While there are in fact some 30 species growing, the predominant impression from the waterside is of reeds. These form a happy habitat for a variety of birds – on a short morning cruise, a group of visitors saw ducks, coots, swans, cormorants and kingfishers.
A survey to be undertaken shortly will measure the presence of invertebrates and, while the longed-for otters have not yet arrived, there is an air of hope that they will make it there one day.
Bioengineering company Salix, which supplied the 400,000 plants used to line 6km of riverbank, normally sees its primary role as soil stabilisation. 'In this case biodiversity came first, followed by soil stabilisation,' said technical director David Holland.
As with the planting on dry land, a considerable amount of experimentation was needed. Although all the soils had been treated and cleaned, high tides could deposit a considerable amount of silt. As a result, both the direct planting of plug plants and the use of seed proved unsuccessful. Salix came up with a solution of growing plants to a degree of maturity in coir mats and then installing those. Only four of the 11,000 mats that it used have failed.
The coir, a byproduct of cocounut, was made compressed in a village in Sri Lanka that had previously been decimated by the tsunami of 2004. It was then made into planting pallets and rolls in the UK. Coir is an ideal planting material as it is pH neutral and biodegradable, disappearing in five to 10 years.
Boat company Lee and Stort is running trips until Christmas, providing an opportunity to see this Olympic achievement from a different angle.