Seaham Beach is a gently sloping resort beach with the designated area measuring approximately
800 metres in length. The beach is mainly sand above the high water mark and a mixture
of sand and rock in the inter tidal area. The designated area is at the southern end
of a two kilometres long bay and it is backed by a promenade. Until 2013, it was
officially called Seaham Hall Beach but the name has been changed to reflect local
custom.
There are no outfalls discharging directly onto the bathing beach but a number of
outfalls discharge to local streams and can temporarily affect bathing water quality
after heavy rainfall. The Environment Agency worked with the water company to investigate
the performance of their sewage network in the area. This investigation reported in
2012 and an improvement scheme was implemented in 2015 to construct storage tanks
at Dalton Park and increase capacity in the sewer network. This reduced the occurrence
of spills, which minimised pollution entering the Dalton Dene and reaching the bathing
water.
Crude sewage discharges in the Seaham area were intercepted and connected to a long
sea outfall to the south of the town in the early 1990's. Improvements were also made
to the inland sewerage network to improve combined sewer overflows (CSO) discharging
to streams that may have been impacting on the beach. A sewage treatment works was
built in 2000 to comply with the Urban Waste Water Treatment Directive.
For the four year (2020-2023) assessment period where data is available, seaweed (macroalgae)
was not assessed as being sufficient to be objectionable, but was observed as being
present on 67% of visits. Environment Agency research suggests this bathing water
does not have a history of large amounts of seaweed (macro algae).
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.
For the four year (2020-2023) assessment period where data is available, phytoplankton
(microscopic algae) was not assessed as being sufficient to be objectionable, but
was observed as being present on 2% of visits. Environment Agency research suggests
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.
This bathing water is subject to short term pollution procedures. The Environment
Agency makes a daily pollution risk forecast at this site based on the effects of
rain, wind and sunlight on bathing water quality. These factors affect the levels
of bacteria that get washed into the sea from livestock, sewage and urban drainage
via rivers and streams and how they disperse.
When these factors combine to make short term pollution likely we issue a pollution
risk warning on this website and the beach manager will display a sign advising against
bathing at the bathing water. After a short term pollution event, levels of bacteria
typically return to normal after a day or so but it’s possible to have several warning
days in a row. Details of the work to reduce the sources of bacteria at this bathing
water are detailed in this profile.
In 2023 9 pollution risk warnings were issued for this bathing water.
All bathing waters have the potential to be affected by a pollution incident and if
this occurs a pollution risk warning will be issued with associated advice against
bathing on this website.
Investigations into the impacts of local streams suggest that occasional high bacterial
counts at this bathing water arise mainly from Dalton Beck, to the south, and are
attributable to intermittent discharges from the sewerage system.
Environment Agency samplers make observations of litter present on the beach at every
visit, this includes assessments of sewage debris, litter and tar. At Seaham Beach
for the four year (2020-2023) assessment period where data is available, sewage debris
was not noted at this site. Litter was not assessed as being sufficient to be objectionable,
but was observed as being present on 39% of visits. Tarry residue was not noted at
this site.
The natural drainage (hydrological) catchment surrounding the bathing water is approximately
6.3 square kilometres, which is a mixture of arable and grassland in the upper catchment
and urban in the lower.
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.