Structures or Craft Impeding Navigation11 August 2017
A new topic has been added to the series of IWA briefing notes which outlines IWA’s views on structures or craft impeding navigation. It is an IWA principle that no navigations should be obstructed by structures either floating or fixed on the bed of the navigation, which reduce the original design width. This is seen as tantamount to filling in part of the navigation and building on it.
IWA recognises that exceptions to this principle may be appropriate in certain situations but each one must be considered on its own merit and if accepted must not be seen as setting a precedent for future development. Structures taking up part of the navigation may impact on the passage and/or mooring of boats, either now or in the future and may restrict other one off uses such as the organisation of local event.
Where such structures have been introduced in the past, design has generally been poor, based on prefabricated units located on floating pontoons. Such structures tend to degrade faster than their equivalent on land and maintenance is more difficult resulting in a progressive deterioration of the visual aspect. Servicing, access and refuse disposal are further problems, which are not easy to resolve for floating structures. Even when such structures are designated with a limited life, in practice this is not always adhered to as removal or replacement is problematic.
An example of this is in Paddington Basin in London where the water area has been reduced and landscaping introduced despite the local IWA Branch submitting an objection. It is a particular concern in this location where maximising moorings is essential to mitigate against the general loss elsewhere in London.
Read the full briefing note on structures impeding navigation.
Photo: Floating gardens at Paddington Basin - a good use of water space? Photo by Roger Wilkinson