LAWPRO
June 2020
Pressures indicated for Tyshe are agriculture and domestic wastewater
The elevated ammonia concentrations could also indicate the presence of farmyard point sources.
Six domestic wastewater systems with high – very high P impact potential along the north and south tributaries of the Tyshe
Agriculture and urban wastewater are listed as the significant pressures
New WWTP for Ardfert was installed in 2017
Dewatering at the Section 4 quarry
The quarry has a section 4 license and is being dewatered – approximately 2500 m3/d on average
Drinking water abstraction at Ardfert South comes under strain in dry summer
Nitrate concentrations are consistently high
Chloride concentrations are consistently high
Elevated nutrients, including orthophosphate, ammonium and nitrate, as well as sediment, are the
significant issues
Hydromorphology
The Tyshe River, falls within the Banna Drainage District. Kerry County Council has a statutory duty to maintain this Drainage District. The River Tyshe flows to the sea at Blackrock. The outfall at Blackrock is vulnerable to blockage from build-up of sand (Flood Risk Management Plan for the Tralee Bay-Feale River Basin, 2018). Sand and seaweed are excavated out of the channel opening. These works currently take place at least every two weeks, but this can be daily in the winter months. The annual cost of these works is estimated at approximately €150,000. The drainage systems back up when this outfall at Blackrock is not clear. Maintenance work is also carried out to keep tidal flaps, approx. 600m upstream of the outfall, functioning. Sluice gates are manually operated to close on high tides to prevent tide backing up on Tyshe River, once every few weeks (Flood Risk Management Plan for the Tralee Bay-Feale River Basin, 2018). As part of a national Preliminary Flood Risk Assessment, discontinuing the existing regime of removing silt and debris from the outfall at Blackrock is being explored