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Wessex Water

Wessex Water covers an area of around 10,000 square kilometres which includes Dorset, Somerset, Bristol, most of Wiltshire and parts of Gloucestershire and Hampshire.

Approximately 284 million litres of water is supplied to 1.3 million people every day from a network of 97 water sources, 110 water treatment works, 209 pumping stations (used to supply water to customers), 340 service reservoirs and water towers and 11,509 km of water mains. Wastewater services are provided for 2.7 million customers with 475 million litres of sewage being treated each day. The company’s sewerage system includes 405 sewage treatment works, 1,003 combined sewer overflows, 1,515 pumping stations and more than 30,000 km of sewers.

Groundwater Impacted Storm Overflows (2024)

Helping nature and society thrive through the design of innovative wetlands

Yeovil Pen Mill WRC (2024)

Reliable approach for phosphorus removal

Durleigh WTC (2023)

In 2019, Wessex Water launched a £51 million project to upgrade the Durleigh Water Treatment Centre (WTC) in Somerset, which had reached the end of its operational life. This project was crucial in maintaining the delivery of high-quality drinking water to a population of 44,500 and was part of the company’s long-term water supply strategy […]

Sherston S101a - First Time Sewerage Scheme (2023)

Section 101a of the Water Industry Act requires that sewerage providers deliver and fund first time sewerage (FTS) schemes where the current drainage for two or more properties is unsatisfactory and where a public solution is viable. Unsatisfactory drainage includes situations where environmental or amenity problems caused by uncontrolled discharges from septic tanks or cess […]

Chippenham Gateway Sewer (2022)

Wessex Water were served under S98 of the Water Industry Act to provide an offsite foul water connection for St Modwen’s new Chippenham Gateway development. This commercial development consists of one million square feet of commercial development and potentially a 150-room hotel. An initial modelling appraisal identified insufficient capacity in the local public sewerage network […]

Wessex Water Resilience Programme (2022)

Flood events in the United Kingdom during the summer of 2007 resulted in a loss of essential services and infrastructure not seen since World War II. Reportedly, over half a million people were left without water or electricity supply, with the estimated cost of the events exceeding £3.2 billion. The subsequent Pitt Review commissioned by […]

Durleigh WTC (2021)

Wessex Water’s £50m project to upgrade Durleigh Water Treatment Centre (WTC) in Somerset is progressing on programme and within budget, despite some particular challenges posed by the Covid-19 pandemic. Work at the site near Bridgwater started in 2019. It is the largest single-value scheme delivered by Wessex Water’s Engineering & Sustainable Delivery (ESD) department and […]

River Parrett Twin CIPP Pressure Lining Renovation (2021)

Large diameter rising main deterioration has become a big capital expenditure because of the risk of major infrastructure failure. The costs of repairing these assets in the event of failure are likely to be very high and characterise a large problem for water and sewerage companies in the UK. Wessex Water’s critical crossing review had […]

West Huntspill WRC Bathing Waters Improvements (2021)

West Huntspill Water Recycling Centre (WRC) is a Wessex Water facility situated south of Highbridge in West Somerset. This environmentally sensitive site is within a National Nature Reserve and adjacent to a Site of Special Scientific Interest and a Special Protection Area (Bridgewater Bay and the Severn Estuary). The facility serves a catchment of 62,000 […]

Durleigh WTC (2020)

Durleigh Water Treatment Centre is located approximately 2km west of Bridgwater, Somerset and is Wessex Water’s second largest surface water treatment works serving a population of 44,500. The site was originally designed to treat up to 28.5 Ml/d, with water drawn down from the 959,000m3 Durleigh Impounding Reservoir. Raw water quality has deteriorated in recent […]

Re–Rounder (2020)

After the implementation of the transfer of private drainage to Wessex Water in 2011, it became imperative that it was necessary to focus more attention on trenchless alternatives for repair of small diameter sewers. Wessex Water’s overall cumulative volume of public sewers doubled overnight from 17,000km to 34,000km, and the majority of that transferred stock […]

Water Supply GRID - Conclusion (2019)

The Water Supply GRID is the largest scheme ever undertaken by Wessex Water and provides important new infrastructure for the south-west region with resilience connections to Bournemouth Water, Bristol Water and South West Water via Wimbleball Reservoir – it is effectively a south-west area regional grid (see Figure 1 below). It has improved interconnectivity within […]

Bournemouth CIS Tunnel Renovation (2018)

Bournemouth is served by a sewerage tunnel known as the Coastal Interceptor Sewer (CIS), an inverted ‘T’ configuration with two tunnels routed parallel to the coastline and a few hundred metres inland. The two tunnels are routed towards each other and form a confluence equidistant along the coast, turning north and heading inland towards the […]

Christchurch STW Inlet Rising Main Renovation (2018)

A burst occurred in a section of 400mm DI rising main within the curtilage of Wessex Water’s Christchurch sewage recovery works in Dorset. The works serve a population in the adjacent catchment of 59,000. The location of the burst was close to a bend in the main, beneath a large diameter primary sedimentation tank, and […]

Frome Valley Relief Sewer (2018)

The Frome Valley Relief Sewer scheme represents a £15m capital investment by Wessex Water to provide additional capacity for the continued development within the North Bristol area. It is the third phase out of a total of four phases which will see wastewater flows diverted from South Gloucestershire to Avonmouth Sewage Treatment Works in Bristol […]

Avonmouth Acid Phase Digestion Remedials (2017)

Wessex Water’s Bristol STW is the largest sewage treatment works within south west region, serving approximately a catchment of 1.1 million people. The works also accounts for more than 50% of region’s sludge treatment. It treats around 100 tonnes dry solid (TDS) per day of indigenous sludge as well as imported sludge to a compliant […]

Bristol Road Sewer Pumping Station (2017)

Burnham Jetty is the only ‘poor’ bathing water site in the Wessex Water region as categorised by the EU Revised Bathing Water Directive. Wessex Water has been working with the Environment Agency and committed £39 million to 12 schemes to improve this rating. Bristol Road Sewer Pumping Station (SPS) and Combined Sewer Overflow (CSO) rebuild […]

MAC Extensometer (2017)

The UK has a tremendous legacy of tunnel construction over the last 150 years, from Joseph Bazalgette’s brick sewers in London, through to reinforced concrete designs based upon early engineers such as François Hennebique. Wessex Water has a considerable cumulative metreage of tunnels constructed over the last 150 years, up to 5 metres in diameter, […]

Fisherman’s Walk Rising Main (2016)

Situated on the Boscombe promenade in Bournemouth on the south coast of England, one of Wessex Water’s sewage pumping station serves a small number of toilet blocks and cafés, connecting them to the main sewerage network. The pumping station is located at the bottom of a steep cliff, 35m high, with a 100mm cast iron […]

Highbridge SPS Stormwater UV Disinfection (2016)

Being classed as ‘poor’ quality, the bathing water at Burnham Jetty was predicted to fail under the revised Bathing Water Directive (rBWD). Investigations during AMP5 showed that improvements to sewage overflows at Highbridge and Bridgwater were necessary to improve compliance; with disinfection of the stormwater discharge at Highbridge Sewage Pumping Station (SPS) being identified for […]

Portbury Wharf STW (2016)

Situated 2 miles from the coastal town of Portishead on the Severn Estuary, Portbury Wharf STW was granted its first consent to operate in 1987. The site underwent a refurbishment in late 2015 and currently services Portishead and the surrounding area, equating to a population in the region of 32,000. Portbury Wharf is comfortably equipped […]

Portland Sewer Collapse (2016)

During extreme weather conditions experienced across the UK in 2014, coastal areas saw conditions that would cause major flooding for residents and major concerns for all utility companies that had infrastructure within the affected areas. Portland being one of the most exposed coastal locations in the South suffered more than other areas. At the height […]

Water Supply GRID - Optimiser System (2016)

Since the start of AMP5 in 2010, Wessex Water, in conjunction with Atkins Ltd and Servelec Technologies, has been developing its 74km Integrated Water Supply GRID to improve resilience, and ensure that a reliable supply of water can be maintained after the output from some sources has been reduced to alleviate low river flows. The […]

Abbotsbury Mains Replacement Scheme (2015)

A challenging water mains replacement project due to narrow streets with listed buildings close to the roadside

Water Supply GRID - Alton Pancras WTW (2015)

Wessex Water are providing additional security of supply and additional strategic storage within the water distribution network in West Dorset

Avonmouth Biomethane Project (2015)

GENeco gas to grid scheme at Bristol STW

Berry Hill STC & Taunton STW (2015)

£16m of improvements to sludge digestion facilities

Charlton Hayes Interceptor Sewer (2015)

Providing a sewer connection to a 2,200 property development via a 30m deep shaft in a dense residential area

Christchurch STW (2015)

Growth scheme - additional treatment capacity for existing sewage treatment works

Water Supply GRID - Sturminster Marshall to Snowsdown Pipeline (2015)

Wessex Water's 9km twin main is the first section of the trunk main to be installed in its flagship project

Water Supply GRID - Allington Reservoir (2014)

Wessex Watre's upgrade capacity by 5Ml to ensure security of supply and meet future area demands

Bristol (Avonmouth) STW - Additional Screening (2014)

£2.5m upgrade of major sewage treatment works requiring additional screening

Electro Scan (2014)

A quantum leap in the identification of sewers subject to groundwater infiltration

Keynsham Requisition Sewer (2014)

A £1.7m requisitioned sewer project serving a 560-property development

Taunton Operation Clean and Clear (2014)

Modernising ageing water mains in Taunton and surrounding areas

Taunton STW (2014)

Major upgrade to largest sewage treatment works in Somerset as part of a staged set of improvements

Water Supply GRID - Update (2014)

Wessex Water’s 8-year programme to resolve resilience issues within the water supply network

Wimbleball Dam Grouting Project (2014)

A new grout curtain constructed beneath Wimbleball Dam has reduced leakage to the lowest recorded rate since construction

Chilthorne Domer STW (2013)

Construction of package sewage treatment works to eliminate unconsented discharge to highway watercourse

Water Supply GRID - Corfe Mullen to Salisbury Transfer Main (2013)

Carefully routed transfer scheme to maximise the use of existing Wessex Water assets

Water Supply GRID - Eliminination of Standalone Sources (2013)

Wessex Water's elimination of standalone sources

Hawkridge Dam (2013)

Concrete repairs to improve the life of the structure

Holdenhurst STW - Inlet Works (2013)

Inlet screens and screenings handling plant replacement

Knightcott to Banwell (M5) Sewer Repair (2013)

Collaboration between agencies to renovate strategic sewer under the M5 motorway in Somerset

Poole STW - Inlet Works (2013)

New inlet works to prevent compliance problems

Shepton Mallet STW (2013)

Phosphorus removal under the Urban Waste Water Treatment Directive and major capital maintenance investment

Trowbridge STW - Acid Phase Digestion Plant (2013)

Acid phase digestion generating green energy with advanced digestion

Columbia Road FAS (2012)

Surface water flood alleviation project in Bournemouth

Shaftesbury Distribution Project (2012)

Strong partnering ensures efficient delivery of a water supply scheme to satisfy the future growth of Shaftesbury

Tarrant Crawford STW (2012)

Growth scheme – additional capacity for existing STW near Blandford Forum in Dorset

Tucking Mill WTW (2012)

A complete redesign and rebuild in the confines of surrounding woodlands and narrow access roads

Weston-super-Mare STW (2012)

£25m upgrade of major sewage treatment works at coastal town

Ashton Avenue Pumping Station (2011)

Refurbishment & upgrade of a critical pumping station

Water Supply GRID - Chirton Phase 2 Pipeline (2011)

Wessex Water's elimination of standalone source

Danesborough Water Supply Zone 21 (2011)

£11.5m scheme to rehabiliate 30km of water mains in the Bridgwater area

Poole STW - Control Equipment (2011)

Wessex Water’s £730,000 project to replace ageing control and monitoring system

Upton Scudamore WTW (2011)

A £1.4m cryptosporidium treatment scheme to safeguard drinking water quality

Evershot STW (2010)

£2.2m dry weather flow exceedence scheme

Salisbury STW (2010)

Significant modifications and additions to the existing works needed

Aqualiner (2009)

A new process for the lining of water and sewer pipes

Bristol City Flood Alleviation (2009)

£9m project to give the city centre area a 1 in 50 year storm protection

Holt & Gaunts Common Sewerage Schemes (2009)

First time sewerage for 300 properties in Dorset

The Limes Flood Prevention Scheme (2009)

Side entry manholes and stop end bends

Bristol (Avonmouth) STW - Advanced Sludge Treatment (2008)

£35m scheme increases electrical self generation at sludge centre

Bristol City Flood Alleviation (2008)

Flood alleviation tunnel

Plimsoll CSO (2008)

Much more than just treading water

Poole STW - Upgrade (2008)

£11m upgrade of major sewage treatment plant at coastal town

Ratfyn STW (2008)

Upgrade of the STW which serves village & nearby communities

Sutton Bingham Dam (2008)

Sutton Bingham Dam remedial work

Corfe Mullen STW (2007)

Replacement screens and screenings handling

Kilve STW (2007)

A high impact yet low profile solution

Malmesbury STW (2007)

New parallel process stream increases treatment capacity

Maundown WTW (2007)

£25m works rebuild by Wessex Water

Yeovil Storm Sewer Renovation (2007)

Customer care & environment concerns key to success

Chew Stoke STW (2006)

Extensions required to meet growing demands

Clarendon WTW (2006)

High tech in the countryside

Monkton Combe Emergency Water Supply (2006)

Safeguarding city of Bath water supply during future droughts

Paulton STW (2006)

£3.1 million project delivered one year ahead of Ofwat deadline

Bath CSOs (2005)

£28.5m scheme to solve uCSO problems in sensitive area

Bridgewater UIDs (2005)

£5 million project cures overflows from six pumping stations

Charmouth STW (2005)

£4.5 million upgrade at Wessex Water’s south coast plant

Dorchester Water Supply (2005)

Resolving existing operational water supply problems

Emergency Water Treatment Works (2005)

6.6Ml/d WTP can be deployed in four shipping containers

Gillingham (Dorset) STW (2005)

Meeting high rate of housing development

Nitrate and Pesticide Reduction Programme (2005)

Wessex Water Services AMP 4 programme

Ringstead Sewerage Scheme (2005)

First time system for outstanding natural beauty area

Shaftesbury STW (2005)

Major upgrade & new ASP meets increasing demand

Thornbury-Aust Pipeline & Outfall (2005)

£3.5m treated sewage outfall into Severn Estuary

Wool STW (2005)

£9m investment improves bathing water quality at resort

Bristol Redland CSO (2004)

Part of Wessex Water’s programme to address 526 UIDs

Kinson, Palmersford & Wimbourne STWs - UV Disinfection (2004)

Installing tertiary ultraviolet (UV) disinfection

Nether Stowey STW (2004)

Improvements & meeting tighter consent

Radipole Sewage Pumping Station (2004)

Major improvements in restricted site & timescale

Taunton (Ham) STW (2004)

A challenge to meet tighter ammonia standards

Bath CSOs (2003)

£28m scheme to remove flooding & pollution risks

Black Lane (Blandford) WTW (2003)

High recovery ion exchange process for nitrate removal

Bristol (Avonmouth) STW - CHP (2003)

New £4m CHP plant saves cash & the environment

Bristol (Avonmouth) STW - Storm Tanks (2003)

Precast concrete panels for storm tanks saved time and cost

Crewkerne East STW (2003)

Upgrading to meet tighter standards & added storm capacity

Friar Waddon WTW (2003)

Cryptosporidium protection for strategic water supply

Lytchett Minster STW (2003)

New storm treatment & UV disinfection

Poole STW - UV Disinfection & Storm Tanks (2003)

£4m project improves discharges quality in Poole harbour

Urchfont STW (2003)

Tertiary BAFF plant for small Wilts village

Avonmouth WwTW (2002)

Sludge digestion enhancement using ultrasound technology

Bristol WwTW (2002)

Secondary treatment upgrade & storm tank storage

Corfe Mullen WTW (2002)

Cryptosporidium protection scheme

Poundbury STW (2002)

Upgraded STW for prestigious scheme

Washpool WTW (2002)

Cryptosporidium protection scheme

Westbury STW (2002)

Plant extensions to meet increased demand