The west facing beach is a long stretch of sand and pebbles backed by sand dunes. It spans 7 kilometres of the coast line, from Tywyn town in the North, to the harbour at Aberdyfi in the south. Tywyn bathing water is located within the Lleyn Peninsula and the Sarnau Special Area of Conservation, with the Dyfi Site of Special Scientific Interest just to the south, confirming the high conservation status of the area. The water quality sample point is located a kilometre west of the car park.
Investigations will be undertaken where and when necessary e.g. where there are elevated bacterial results in the bathing water that cannot be simply explained due to weather conditions.
Natural Resources Wales has developed a good working relationship with Dŵr Cymru Welsh Water and liaison takes place regularly to identify problems that could affect bathing water quality.
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. There are no known misconnections in the Tywyn area.
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.
Streams are typically affected by human or industrial inputs from further up the catchment. A mile north of Tywyn is the River Dysynni, which runs into Cardigan Bay. This drains an agricultural catchment. This watercourse can be a source of reduced water quality after heavy rainfall. In an effort to reduce bacterial concentrations, bacterial samples were collected at a number of points on the streams and rivers draining to the beach during 2019.
The town of Tywyn is served by a conventional sewage treatment plant, but has ultra violet (UV) disinfection as an additional final stage of treatment. The UV process is designed to kill the majority of the bacteria and virus present in the effluent in order to protect the bathing water quality.
Natural Resources Wales samplers make visual observations of the beach at every visit. This includes assessments of sewage debris, animal faeces, litter and oil or tar. At Tywyn, data are available for the four year assessment period from 2020-2023. Sewage debris was not observed at this bathing water. Animal faeces was not noted at this site. Trace amounts of litter were observed at the bathing water between twenty and thirty percent of occasions. Oil and tarry residues were not noted at this site.
There are a number of caravan sites and small seasonal businesses located near to the beach. These are connected to the main sewer system. Natural Resources Wales continues to work with private owners to address potential pollution sources to the bathing water. This work involves where necessary, advisory mail drops, dye tracing, misconnection surveys and general 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 was 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 surrounding the bathing water is semi urban, dominated by the town of Tywyn. This contains a number of commercial premises including several caravan parks. To the north of the bathing water is the mouth of the Dysynni, with the farmland of Bro Dysynni to the north-east. Afon Dysynni drains the southern flanks of Cadair Idris, with Craig yr Aderyn / Birds Rock located several kilometres inland.
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 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.
It is 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. The following sections serve to highlight potential sources of pollution, conditions under which they may arise and measures being put in place to improve water quality.
