There is an emergency/storm overflow from the West Hoe Tanks that discharges to Plymouth
Sound approximately 420m southwest of Plymouth Hoe West bathing water.
There are emergency and storm overflows that discharge into Plymouth Sound from neighbouring
urban catchments. The operation of the overflows can lead to a temporary drop in water
quality in the Plymouth Sound and at Plymouth Hoe West bathing water.
South West Water, in close partnership with the Environment Agency and Plymouth City
Council, are continuing a programme of improvements to reduce the operation of overflows
and reduce surface water flood risk within Plymouth. Work includes reducing infiltration
and surface water run-off into the sewer network.
The sewage treatment scheme for Plymouth was completed by South West Water during
the 1998 bathing season. A large number of untreated sewage discharges to Plymouth
Sound and the Cattewater were removed and transferred to Plymouth sewage treatment
works (STW). Sewage is treated to a secondary standard with ultraviolet (UV) disinfection.
Improvements to several untreated discharges into the lower Tamar Estuary (Hamoaze),
were also completed at that time. Since completion of this scheme the bathing water
quality at Plymouth Hoe West has improved significantly.
Wastewater flows to Saltash STW were transferred to Ernesettle STW in 2000 and secondary
treatment was completed by April 2001. A total of 12 discharges to the River Tamar
were improved by the end of December 2002, and a further 16 discharges by the end
of March 2003.
Storm overflow event duration monitoring (EDM) was installed at eleven storm discharges
to the Plym and Plymouth Sound by April 2012 and a further five in March 2016. Storm
overflow event duration monitoring (EDM) was installed at 31 storm discharges to the
Plym and Plymouth Sound by March 2018. UV disinfection was installed at Plymouth Central
STW overflow by March 2018. Further improvements to the sewer network are due by March
2025.
The Environment Agency have carried out extensive additional catchment monitoring
in the Plymouth area alongside the Environment Agency routine bathing water monitoring.
The Environment Agency also used a DNA tracing technique to help us identify whether
sources of faecal pollution are human or animal. The aim was to pinpoint pollution
problems in the catchments flowing into Plymouth Sound and the local sewerage infrastructure
so that the Environment Agency can improve water quality at the bathing waters.
Investigations showed that the urban drainage problems were a source of pollution
to the bathing water. As a result, between 2012-2014, the Environment Agency, in partnership
with South West Water and Plymouth City Council, investigated the sewerage network
in Plymouth to identify and rectify issues. The project focused on misconnections
entering stormwater drains and polluting local watercourses. However other issues
were identified such as issues with South West Water assets, private treatment plants
and blockages due to fats and grease. More than 250 issues were identified and resolved.
South West Water continue to investigate a small number of polluted outfalls which
show signs of misconnections.
The urban area of Plymouth immediately behind the beach is served by a combined (surface
and sewer) system. The outfall from the Tinside Swimming Pool discharges to Plymouth
Sound 220m southeast of the Environment Agency monitoring point.
For the four year (2020-2023) assessment period where data is available, seaweed (macroalgae)
was assessed as being sufficient to be objectionable for 23% of visits, with 73% of
visits noting the presence of seaweed (macroalgae). The bathing water at Plymouth
Hoe West can become covered with large amounts of seaweed, depending on tides and
the weather. This bathing water has a history of large amounts of seaweed.
Wrongly connected domestic waste water pipes can affect the bathing water quality.
We have checked the local sewerage system for misconnections. We are working with
Plymouth City Council and South West Water to identify and rectify any problems when
they arise.
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 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.
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, tide and wind 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 4 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.
Streams and rivers are typically affected by human sewage, animal slurry and runoff
from roads. The Tamar and Plym rivers can affect bathing water quality at Plymouth
Hoe West during and after heavy rainfall.
The Plymouth STW outfall discharges to Plymouth Sound approximately 420m southwest
of Plymouth Hoe West bathing water. This discharge is disinfected and designed to
protect bathing water quality.
Environment Agency samplers make observations of litter present on the beach at every
visit, this includes assessments of sewage debris, litter and tar. At Plymouth Hoe
West for the four year (2020-2023) assessment period where data is available, sewage
debris was not noted at this site. Litter was assessed as being sufficient to be objectionable
for 5% of visits, with 75% of visits noting the presence of litter. Tarry residue
was not noted at this site.
Where the Environment Agency have found polluting discharges from private properties
close to the bathing water they have been connected to the sewerage system. If any
concerns arise, the Environment Agency will investigate and request immediate remedial
action from those responsible.
The catchment surrounding Plymouth Hoe West is approximately 171,000 hectares. It
includes the Tamar and the Plym Estuaries which enter the sea in Plymouth Sound.
The Tamar system includes the rivers Tamar, Tavy, Tiddy, and Lynher. The River Tamar
rises close to Bude on the north coast of Cornwall and flows south for 50 kilometres
(km) before becoming tidal approximately 30km inland at Gunnislake Weir. The Lyhner
rises on Bodmin Moor and flows for approximately 34km to the estuary at Plymouth.
The Tiddy joins the Lyhner in the upper estuary.
The River Tavy rises in Dartmoor National Park and falls steeply for 28km to the tidal
limit at Lopwell, before joining the Tamar Estuary 10km upstream from Plymouth Sound.
The River Plym rises on the open moorland of south Dartmoor and becomes tidal five
and a half kilometres before entering the sea at the eastern side of Plymouth Sound.
The major maritime and industrial city of Plymouth contrasts strongly with the rural
character of the upper catchments, which are populated by specialist dairy, beef and
sheep farms and some arable land producing potatoes and maize. Historic mining and
industrial activity has significantly affected land and water quality.
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.