Sussex's coastline has long been a favourite destination for locals, tourists and wildlife. However, the deterioration of sea water quality in the region has been a growing concern in recent years.

One significant factor impacting sea water quality is the operation of storm overflows from the region's sewage system. Storm overflows are designed to prevent flooding during periods of heavy rain by releasing excess water, which is typically diluted with rainwater and approved by the Environment Agency. However, there are instances when storm overflows operate even on dry days, known as 'dry spills.' These unconsented releases can occur due to various reasons, including groundwater infiltration, slow drainage or equipment failures.

Southern Water, like all water companies, holds permits issued by the Environment Agency that outline consented and unconsented release conditions. The company has to report every release to the Environment Agency. Pollutions from spills doubled in number from 2020 to 2021 and the company was fined £90 million after pleading guilty to 6,971 unpermitted sewage discharges. Subsequently, Southern Water has set up a Storm Overflow task force with a commitment to cutting storm overflows by 80% by 2030 and to zero by 2040. They have also set up a pollution reporting hotline (0330 303 0368) for those wanting to report a concern. These efforts are being monitored carefully by charities and citizen groups who remain alert to any 'greenwashing' or misrepresentation of data.

While storm overflows play a role in water quality, they are not the sole contributing factors. Other sources of pollution include sea birds, dog excrement, decaying seaweed, algae blooms, and surface water run-off from roads and agriculture. As we experience more extreme weather events in both summer and winter months, flooding and surface water can add significantly to poor river and marine water quality. Increased urbanisation with hard surfaces, like roads and paved gardens, hinder the absorption of rainwater into the environment.

The Environment Agency collect seawater samples weekly during the summer bathing season and classify the water quality as excellent, good, sufficient, or poor. This monitoring helps identify areas that need intervention and improvement. Aldwick, Bognor Regis, just outside the corridor route, is one of the Sussex beaches where the water quality has been classified as "Poor." Analysis indicates that high levels of bacteria are unlikely to be solely attributed to sewer overflows alone. Instead, "misconnections", where foul drainage is wrongly connected to surface water sewers by developers and plumbers, have been identified as another potential source of the problem.

In response to growing concerns about sewage pollution, activists from Surfers Against Sewage (SAS) organised protests in Sussex this spring. It brought together swimmers, fishing communities, paddle boarders and sailers calling for an end to sewage discharges into bathing waters and a substantial reduction in sewage pollution. There is fury at the slow pace of change and protesters have called out seemingly weak regulation and lack of engagement by government departments with water company taskforces.

There is a growing swell of support for nature-based solutions, including "bio-filtration" (using vegetation, wetlands and soils to filter poor quality water), present a promising and sustainable approach to tackling water quality issues. Constructed wetlands, rain gardens, permeable pavements, riparian buffers, and green roofs are just a few examples of these innovative methods. By harnessing the power of natural processes and ecosystems, these solutions effectively filter and treat polluted water, preventing harmful run-off from reaching water bodies. Whether it's using plants and microorganisms to cleanse water in constructed wetlands or creating green roofs to promote evapotranspiration and reduce run-off, each nature-based solution contributes to cleaner water and healthier environments. Embracing these approaches, along with reforestation and conservation agriculture, will undoubtedly lead to significant improvements in water quality, benefiting both humans and the natural world.

To this end, water companies are investing in "Integrated Constructed Wetlands" to manage waste water using natural methods. A new £2.1 million wetland is being developed alongside an East Sussex wastewater treatment near Haywards Heath in an attempt to protect the quality of water in the River Ouse. The new wetland has a lattice of native plants in shallow water, which naturally filter and clean all water passing through to remove nutrients and filter the output of storm overflows when sewer volumes peak after heavy rainfall. These wetlands, even those constructed, offer safe haven for biodiversity. If these trial sites go well, there are likely to be more of these wetlands along the corridor.

The Weald to Waves community is working hard to address the water quality challenges along the corridor. Collaboration among highways, local authorities, planning teams, agriculture, regulators, and the government is necessary to reduce the volume of water entering the sewer system. Across our farms, gardens and greenspaces, we can help to slow and stop the flow of surface water through rainwater harvesting, natural planting, increasing organic matter in our soils (for example, chopping and droppping garden cuttings), avoiding bare earth and closely cut, patchy lawns allowing it to be better absorbed before it hits the system.

Additionally, river recovery work planned across Sussex's major catchments by a strong network of partners and land managers will help in slowing, holding, and filtering water to prevent pollutants from reaching the sea.

While the primary responsibility lies with those with a mandate to manage our water, bathers can also play a small role in protecting water quality by taking responsibility for their waste, disposing of rubbish properly, and ensuring that dogs do not foul on beaches. The beach cleans across Sussex's shoreline each season are a brilliant example of citizen action.

Our marine and underwater worlds are the least visible to us and therefore we need to go the extra mile to document the harm done to them by human activity. Without an improvement in water quality, efforts to restore the kelp forests or oyster beds off the Sussex coast will be repeatedly hindered and potentially destroyed.

To find out more about this issue, visit these links:

Rivers Trust - Raw Sewage in Rivers

House of Lord's Library on Sewage in UK Waters

Surfers Against Sewage

More information on Southern Water's new constructed wetland on the Ouse