Using an innovative Catchment Nutrient Balancing (CNB) approach to improve river water quality: A case study from a rural sub catchment in Cumbria, United Kingdom: PRESENTATION ONLY
Nalika Rajapaksha, Integrated Catchment Strategy Manager, United Utilities
(Free)
Nutrient pollution
• Water quality is a key concern, and many water quality problems arise from multiple sources of pollution.
• To achieve the regulatory P reduction objectives, WwTW permit limits are becoming increasingly stringent.
• Tighter permits in smaller WwTWs can make P removal practically difficult as well as expensive.
• The challenge of meeting the P objectives in rural catchment often goes beyond water company activities.
Challenges and opportunities
• The River Petteril is a tributary of the River Eden, Cumbria, UK and the catchment is mainly agricultural.
• Local ecology is impacted from significant nutrient inputs – Phosphorus from wastewater discharges and agriculture.
• To achieve good ecological status, action was required to reduce phosphorus load entering the river.
• In AMP6 and AMP7, four of UU’s WwTWs in the Petteril catchment had WFD regulatory drivers.
• From baseline data it was clear that the WwTW alone would not resolve the problem.
• We used our innovative CaST Strategy and initiated a Catchment Nutrient Balancing (CNB) approach.