Phosphate removal initiatives make waves in Wales

The Welsh government’s river quality taskforce has urged water companies to review existing discharge consents and spending on removing phosphate from its sewage treatment works.

Ministers are anxious to make sure all possible measures are being taken to protect those rivers which have been designated as special areas of conservation (SACs) but which are failing to meet the ecological standards required by the environmental regulator, Natural Resource Wales.

Phosphate pressures come from multiple sources and includes wastewater infrastructure – storm overflows and consented activities such as sewage treatment works.

The issue is proving both an environmental issue and a problem for new developments, particularly housing. Schemes for hundreds of new homes across the country have stalled because allowing the projects would increase the phosphorus load in rivers which are also SACs.

One possibility under consideration is the introduction of so-called nutrient trading, a move which would see a system of pollution mitigation credits akin to carbon offsetting. Dwr Cymru Welsh Water is currently investigating the feasibility of such a trading scheme for the river Usk catchment.

The water company plans to invest an extra £100m before the end of 2025 to reduce phosphate discharges from its wastewater treatment works and to reduce the impact of combined storm overflows. This is in addition to the £836m already budgeted in its latest business plan. This should support improvements in the Usk, Wye, Cleddau and Teifi rivers.

Also under consideration is a move to system of catchment-wide consents rather than the current site-based permitting approach.

Welsh Water chief executive, Peter Perry, said: “We need to work together at a catchment level to ensure that the interventions, investments and permitting regime are delivering the required improvements efficiently and that inevitably limited funding has the greatest impact.”