2014 Bathing Water Profile for Aberdyfi
-
Located on the coast of Gwynedd in the Snowdonia National Park, the beach faces south west towards Cardigan Bay, at the mouth of the River Dyfi. The beach is steep and shelving with strong currents from the Dyfi estuary. A harbour can be found to the east of the beach, with dunes to the north west. The coastal waters and surrounding area are listed as a Ramsar site, and also include the Dyfi Estuary Special Protection Area, the Lleyn Peninsula and Sarnau Special Area of Conservation and the Dyfi Site of Special Scientific Interest, confirming the high conservation status of the area. The water quality sample point is located a kilometre west of the car park.
-
Gwynedd
-
Pre-season (before the 1st of May) and mid season (during the bathing water season) inspections are carried out by Natural Resources Wales in partnership with the local authority and the water company. Natural Resources Wales is currently working with Gwynedd Council and Dŵr Cymru Welsh Water to establish sources of pollution in and around the Dyfi estuary. Dwr Cymru Welsh Water has made the required improvements to Machynlleth sewage treatment works and storm discharge. Further checks are to be made in 2013. Awaiting modelling of the bacterial loadings in the catchment.
-
There is a combined storm overflow in the centre of the town, with an emergency overflow into the Dyfi Estuary, close to the jetty. This is not exposed at low tide.
-
Natural Resources Wales has developed a good working relationship with Dŵr Cymru Welsh Water and liaises regularly to identify problems that could affect bathing water quality. Dŵr Cymru Welsh Water are automatically notified of all bathing water quality sample failures. This information is reviewed and reported to Natural Resources Wales and any possible problems with Dŵr Cymru Welsh Water assets are highlighted. These assets include sewage treatment works, pumping stations, storm overflows, storage tanks and general pipe work. Bathing water quality failures are investigated by Natural Resources Wales and cross-referenced with this information to ensure all Dŵr Cymru Welsh Water facilities have been operating as designed during periods of reduced water quality.
-
Natural Resources Wales works with Gwynedd Council and Dŵr Cymru Welsh Water to establish sources of pollution around Aberdyfi bathing water.
-
This bathing water does not have a history of large amounts of seaweed (macroalgae).
-
During investigations in 2009, high levels of faecal contamination were discovered in the harbour area. Further investigation with Gwynedd Council revealed the source of this bacterial input to be a property in the town. Sewage drainage from the property had been connected to the surface water drain, rather than the foul water drain. The property owners were notified and this issue was resolved within days of the investigation. No further issues have been reported. Modern sewerage systems have two separate systems, one takes foul sewage to sewage treatment, the other takes rainwater runoff through surface water drains to rivers, lakes and the sea. Misconnections occur when waste water pipes are plumbed into surface water drains instead of the foul water sewerage system. This can give rise to pollution when the waste water is discharged directly to the environment through the surface water drain. For example, a washing machine or toilet may be incorrectly plumbed so that it discharges to the surface drain rather than the foul sewage drain.
-
Phytoplankton (microscopic algae) naturally increase in number at certain times of the year. This process is known as a phytoplankton bloom. Algal Blooms can occur at any beach during the bathing season and are usually noticeable by a surface scum. This beach has no history of such blooms.
-
2014 Bathing Water Profile for Aberdyfi
-
Streams are typically affected by sewage or industrial run off from further up the catchment. High bacterial counts have been found in the River Leri. Catchment investigations into the source of the bacteria were carried out in 2011/12. The Dyfi is a large watercourse, with a catchment that extends into the upland areas of mid Wales. Both the Dyfi and the Leri are sources of reduced water quality after heavy rainfall.
-
Natural Resources Wales has worked with farmers over recent years to reduce the impact of the agricultural industry on the water environment. Agricultural run-off continues to impact on water quality here. This also affects bathing water quality, particularly during periods of heavy rainfall. Further investigations and farm visits are planned to take place to advise on land management and share best practice techniques.
-
Natural Resources Wales continues to work with private owners regarding potential pollution sources to the bathing water. This work involves where necessary, advisory mail drops, dye tracing, misconnection surveys and face to face meetings. Poorly maintained private sewage treatment facilities could be a source of pollution, therefore the registration of all private sewage systems in Wales was required by 30 June 2012. The primary aim of this exercise is to provide increased protection for the environment and sensitive features such as bathing water beaches. Where properties are identified in the catchment that are not on mains sewerage, Natural Resources Wales will endeavour to ensure registration has been made.
-
The natural drainage (hydrological) catchment is largely rural, dominated by agriculture.
-
2014 39050:1
-
Seaweed (macroalgae) and phytoplankton (microscopic algae) are a natural part of the marine and freshwater environment. Below we note whether these have been recorded in quantities sufficient to be a nuisance.
-
The majority of sewers in England and Wales are “combined sewers” and carry both sewage and surface water from roofs and drains. A storm overflow operates during heavy rainfall when the sewerage system becomes overwhelmed by the amount of surface water. The overflow prevents sewage from backing up pipes and flooding properties and gardens. An emergency overflow will only operate infrequently, for example due to pump failure or blockage in the sewerage system.
-
Heavy rain falling on pavements and roads often flows into surface water drains or highway drains, ending up in local rivers and, ultimately, the sea. The quality of bathing water may be adversely affected as a result of such events.
-
Swimming not advised at or around low tide due to risk of reduced water quality. It is the Environment Agency and Natural Resources Wales role to drive improvement of water quality at bathing waters that are at risk of failing European standards. It is natural for water to run off the land to the sea. Water quality at a bathing water is dependent upon the type and area of land (the catchment) draining to the water and the activities undertaken in that catchment.
-
Discharges from sewage treatment works have improved substantially in England and Wales since the 1980s.
-
