Maintaining clear water in the navigation requires the removal of silt build up on the bed of the canal, the removal of weeds from the water itself and the cutting back of reeds and other plants near the banks. The machinery to do so varies, depending on the job in hand.
Today, both spot dredging and dredging of longer stretches is done mainly from the bank with an excavator on the end of an articulated arm. When hauling out silt from the water, a bucket with drainage is used, while bank work uses an ordinary bucket. The matter is lifted out of the canal and loaded onto a truck, for safe disposal.
Removing weeds on a regular basis, from the channel requires either a weed cutter or a weed extractor. The former, currently used by Waterways Ireland, cuts the weed to a depth of a metre or so. The debris is then left on the bank for later collection.
Reeds, shrubs and trees are cut back in late autumn to early spring, being mindful of the young wildlife in the foliage from late spring onwards. Weed cutters are used to cut back the reeds, and hedge cutters attached to an articulated arm are used to keep the shrubs and trees trimmed.
Here are images of work in progress, the removal of silt and weed from the canals. Some are from times past, others more recent in 2012/13. Shown are excavators and small and large weed cutters in action, all from the Waterways Ireland fleet. Also shown are pictures from the Weeders Digest showing a weed harvester/puller in action.