Southern Water commits to action and investment to improve our Harbours


A package of investment and an offer to host a summit of senior leaders aimed at helping to improve the water quality and important natural habitats of Chichester and Langstone Harbours is being announced by Ian McAulay, CEO of Southern Water today.

Part of the investment is a new £5m environmental improvement fund. Central to the company’s commitment to the harbours is an undertaking that a proportion of this £5m will be invested with partners on initiatives that deliver both nature-based solutions and environment net-gain for both harbours. 

This announcement follows a series of top level meetings with local campaigners and political leaders including Gillian Keegan MP for Chichester and Alan Mak MP for Havant.

Southern Water is investing £1.7 billion over the next four years across the south-east to improve the capacity and efficiency of the waste water network and reduce the number of releases from Combined Sewer Overflows (CSOs).

This includes £13 million to be invested to improve instrumentation and data capture that further reduces the risk to the environment from storm overflows, including at Budds Farm, which releases into Langstone Harbour.

A major £6.5 million scheme to reduce groundwater infiltration into the vast Chichester sewer network is also planned. Every drop of groundwater that can be kept out of the network reduces the need for storm overflows.

This investment builds on the £3.2 billion Southern Water has already spent since 2015 to improve and maintain its assets across the south-east. Action already taken to reduce the contribution that wastewater treatment works make to nutrient enrichment in the harbours includes:

• A 90 per cent reduction in the nitrates going from wastewater treatments works into the harbours. These works now contribute less than 10 per cent of the overall nitrate levels in the harbours and all operate within nitrate permit conditions.

• CSOs contribute just one per cent to the nitrates in the harbours and all works operate well within nitrate permit conditions.

• Creating one of the few CSOs in the UK with UV treatment to sterilise storm releases at Chichester.

• An online storm release notification system, Beachbuoy that helps our customers and partners by providing near real time information about CSO activity at designated bathing waters and recreational watercourses. Beachbuoy will cover all 83 designated bathing waters and Chichester Harbour and Langstone Harbour by the end of May.

• A roll out of Event Duration Monitoring (EDM) technology across 98 per cent of the network since 2017 to build a clearer and more detailed picture of the use of CSOs, that helps to target future investment and operational activity. Further investment to ensure 100 per cent coverage by 2025 is in place. Southern Water led the industry in the roll out of EDM technology.

• One of the first published Pollution Incident Reduction Plans (PIRP) which details a programme of activities to deliver a sustainable reduction in pollution incidents. It is published on our website:

Ian McAulay said: “Saving the internationally important and threatened habitats at Chichester and Langstone harbours is incredibly important to us, our customers and our stakeholders. We are absolutely committed to playing our part by reducing the harm to the harbours’ waters from Combined Sewer Overflows (CSOs).”

He added: “Our new £5m environmental improvement fund, as part of our overall spending plans for 2021/22 and beyond, clearly demonstrates Southern Water’s commitment to being an active and involved member of the newly formed Chichester Harbour Protection & Recovery of Nature group (CHaPRoN). This emerging group is a very welcome and positive step forward in forging a powerful partnership to save our harbours.

“Working together with a shared action plan we truly believe we can make significant strides to improve the water quality of our harbours, this will benefit the environment, water users and support the local economy.

“As part of our commitment to working within this partnership, we are offering to host a summit of senior leaders at which I hope we will agree a shared action plan.

“In one of the most water stressed regions in Europe we believe that more can be done to ensure housing and buildings are both water and nutrient efficient and that sustainable drainage solutions should be incorporated into all new developments. We also want to champion the importance of labelling appliances for their water efficiency.

“We advocate the importance of all farms in the catchments of the harbours following the code of good agricultural practise and a moratorium on emptying of bilges while in the harbour.
“Having a shared understanding of the sources and pathways of nutrients will enable all partners to target our efforts where they will have most effect.”

James Seymour, Natural England Area Manager (Sussex & Kent), said:
“Wildlife is declining affecting the people who use and live around the harbours, so immediate and urgent commitment is needed by all stakeholders to address the challenges we identified in our 2021 condition report. We welcome Southern Water’s announcement to support people working together in collaborative projects such as CHaPRoN to save the harbours and their wildlife for the enjoyment now and for future generations.”

Gillian Keegan, Member of Parliament for Chichester said:
“I welcome Southern Water’s investment plans, which are definitely a step in the right direction, and their efforts to improve community engagement. However, it is of course important that it leads to tangible results.

“I will continue to work closely with Southern Water, all the statutory agencies, my neighbouring MPs and Government Ministers to address the current declining state of the harbour. I’m looking forward to hearing more detail on the proposals to ensure we develop a solution-focused approach.”

Alan Mak, Member of Parliament for Havant said:
“I’ve campaigned for several years to improve water quality in Langstone and Chichester Harbours, and I look forward to continuing my work Southern Water, neighbouring MPs, community representatives and statutory agencies.

“Southern Water will play a key role in reducing discharges and ending storm overflows, and this investment is a good first step. I look forward to their detailed plan setting out how they will meet the new legal obligations set by the Government.”

Richard Craven, Director & Harbour Master for Chichester Harbour Conservancy, said: “This new investment by Southern Water is to be welcomed. However, we wait to see how much of the £5million environment investment fund will be directly invested in helping to save the habitats and wildlife of Chichester Harbour. We look forward to seeing the detail and attending a summit that can drive forward the action we all know is urgently needed.”

Chichester Harbour Protection & Recovery of Nature (CHaPRoN), an exciting, emerging partnership project looking for urgent action to restore habitat, improve water quality and reduce bird disturbance working with key stakeholders and local communities.

The issue of Combined Sewer Overflows (CSOs) and storm overflow releases into the environment have become a growing issue of concern as a result of greater transparency of Event Duration Monitoring (EDM) data. Southern Water has been at the forefront of this growing openness and transparency of information about releases from wastewater treatment sites since 2017.

Our online storm release notification system, Beachbuoy, helps our customers and partners by providing near real time information about CSO activity at designated bathing waters and recreational watercourses. Beachbuoy currently covers two harbours in our region (including Langstone Harbour) as well as a selection of bathing waters, and we plan to include all 83 designated bathing waters in our region before the start of this year’s bathing season..

In 2017-2018 of the 83 designated bathing waters in the region, each of them achieved the minimum standards required and in 2019 58 were rated as ‘excellent’ and 21 ‘Good’ compared to 1989 when 31% failed to meet the more basic standards that were required at the time. Southern Water has invested more than £32 million on improving bathing waters in the past five years including major programmes in Worthing, Sussex and Shanklin, Isle of Wight.

Bathing water at beaches across the South East have achieved their highest ever ratings in Defra’s Bathing Water sampling regime. We continue to expand our Bathing Water Enhancement Programme, with a new five year phase which aimed to bring a further seven bathing waters across the region to ‘excellent’ standard in 2020.

EDM data helps to build a clearer and more detailed picture of the use of CSOs, which in turn helps to target future investment to tackle sites where the risk of pollution are greatest. Our in-depth analysis is helping us to understand where and how our sites are most likely to impact the environment. Understanding what can go wrong and why allows us to focus our attention and investment on areas which will deliver the biggest reduction in pollution incidents.

We’ve developed an agile and detailed programme of activities to deliver a sustainable reduction in pollution incidents. Our Pollution Incident Reduction Plan is published on our website

CSOs are an integral part of the network managing the flow of wastewater across the UK. Wastewater comes from bathrooms, kitchens and appliances.

The network was largely built in the Victorian era and is vital to reducing the risk of internal flooding in homes, businesses, schools and hospitals.

During wet weather, rain run-off from buildings and roads, also enters CSOs, diluting the wastewater they are designed to carry away for treatment. Storm overflow tanks help to contain excess wastewater but once these are full, releases of diluted wastewater are permitted.

Chichester and Langstone Harbours are among the locations where these releases happen. They are strictly controlled through permits issued and monitored by the Environment Agency.

Climate change, leading to greater rainfall has put pressure on an infrastructure which has not kept pace with population growth.

Groundwater infiltration is a key challenge in reducing storm overflows. To reduce the incidence of spills we are embarking on a project to reduce infiltration into the sewer network. This will commence during 2021 and will involve the monitoring of flows in the sewer network relative to groundwater levels and rainfall. This will inform where to target concentrations of flow monitoring devices to home in on areas of particular concern. Once hotspots have been identified we will progress to the next stage of surveying individual sewer runs by scanning equipment which will check for leaking joints and pipe defects which are allowing flow into the system.

Once these weak points are identified we will use no-dig techniques which have been enhanced in recent years, to create a permanent seal to the pipes.

The Chichester sewerage system is vast. The total length of the public drainage system which conveys flow from properties to the recycling centre being around around 180 km, once the privately owned drains are added to this the overall length will be well in excess of 300 km. 

Nutrients also enter the harbours’ waters from sources other than CSOs. Environment Agency*

figures show that wastewater from our wastewater treatment works is a relatively small source of these nutrients.

In Langstone Harbour wastewater treatment works direct to the harbour account for four per cent of the nutrients.

Urban and agricultural sources such as animal manure and crop fertilisers account for 55 per cent of the nutrients and 40 per cent are coastal background, including decaying sea lifeFor Chichester Harbour the figures are 12 per cent from wastewater treatment works, 34 per cent from urban and agricultural sources and 54 per cent from coastal background.