Durdle Door West is on the Dorset coast, and is part of the Purbeck Heritage Coast.
It is a fairly remote beach of sand and shingle, approximately 750 metres wide, and
backed by high cliffs.
For the three year (2021-2023) assessment period where data is available, seaweed
(macroalgae) was assessed as being sufficient to be objectionable for 4% of visits,
with 80% of visits noting the presence of seaweed (macroalgae). This bathing water
does not have a history of large amounts of seaweed (macro algae).
For the three year (2021-2023) assessment period where data is available, phytoplankton
(microscopic algae) was not noted at this site. Phytoplankton (microscopic algae)
naturally increase in number at certain times of the year. This process is known as
a phytoplankton bloom. This bathing water does not have a history of phytoplankton
blooms.
The risks to human health from contact, ingestion or inhalation with marine algae
that currently occur in UK coastal waters are considered to be low. However, some
individuals may be more sensitive and display some reactions.
A common marine algae found in UK coastal waters is Phaeocystis, which is often mistaken
for sewage as it forms foam and a brown scum, but it is non-toxic.
There are no active pollution risk forecasts made at this bathing water. However any
bathing water has the potential to be affected by a pollution incident and if this
occurs a pollution risk warning with associated advice against bathing will be issued
on this website.
Environment Agency samplers make observations of litter present on the beach at every
visit, this includes assessments of sewage debris, litter and tar. At Durdle Door
West for the three year (2021-2023) assessment period where data is available, sewage
debris was not noted at this site. Litter was assessed as being sufficient to be objectionable
for 4% of visits, with 96% of visits noting the presence of litter. Tarry residue
was not assessed as being sufficient to be objectionable, but was observed as being
present on 4% of visits.
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 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 the Environment Agency role to drive improvement of water quality at bathing
waters that are at risk of failing higher 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.