Following his involvement in our Water Infrastructure and Capital Investment Conference we’ve been speaking exclusively to John Thompson – Executive Director of Engineering and Sustainable Delivery at Wessex Water…

Q. Wessex Water’s catchment area was recently added to the Environment Agency’s water stressed areas, what are your priorities for your water resources management plan?

We are currently reviewing and updating our Water Resources Management Plan, which was published in July 2019. This review will include updated modelling to take account of future water demand, climate change and environmental factors. We are working collaboratively with the new West Country Water Resources Group, including Bristol Water, South West Water and our regulators, to develop a longer-term water resources strategy. This plan will be available for consultation in August 2021.

These plans will cover several elements, including reviewing our own water resource availability under a range of climate change scenarios and future demand. Management options are likely to include assessing current abstraction levels, opportunities to develop new resources, water efficiency and demand measures, such as metering and further addressing leakage. We are undertaking several investigations in this investment period to better understand the environmental impacts of current abstraction levels to assess their long-term sustainability.

Q. How will your plans help to improve the ecology of local rivers within the South West?

Within this investment period we have a considerable phosphorus removal programme, including asset improvements and catchment measures to reduce discharge levels into watercourses. This includes removing more than 250 tonnes per annum (tpa) phosphorus from our discharges by 2025, over and above the 450tpa removed across our area since 2000.

Our performance commitment in the Hampshire Avon could deliver a further 12tpa phosphorus reduction, improving up to 76km of river in the catchment by 2025.

We are targeting removing 100tpa nitrogen through from the Poole Harbour catchment through a combination of catchment offsetting and the construction of a second nitrogen removal treatment plant (at Wareham). This will improve 26km of the river Frome and Poole Harbour.

Where we are reducing nutrient loads through catchment management, we are focusing on delivering wider environmental benefits, such as wetland creation, grassland reversion and woodland creation to provide further habitat and biodiversity improvements. These measures will not only provide nutrient reduction and habitat creation, but also reduce soil run-off, further improving the ecology of the rivers in our area.

Our water supply grid was recently completed in 2018, this delivered a 23.5Ml/d reduction to the volume of water abstracted from the Chalk aquifer supporting the Hampshire Avon. We are investigating the river improvements resulting from this scheme, including improvements to river flow, ecology and mesohabitats.

All our investment is preceded by intensive environmental investigations to provide sound science, data and evidence on the impacts resulting from our operations. This ensures that we invest where we are having an impact and that we can be confident that the interventions delivered will have a material environmental benefit.

Q. Improvements to waste water management and treatment have been a recent focus across the Water Industry, how is that reflected in your plans?

Water Industry National Environment and growth programme’s are over 60% of our overall capital investment.

Q. How will the expansion to capacity in your capital investment programme help to catalyse the development of new housing?

Our designs for expansion to capacity have a horizon of 2040, thus accommodating future growth for the next 20 years. In addition, we have specific investment for growth including the North Bristol tunnel, which provides increased capacity for the future development of North Bristol as well as expansion works at both Saltford and Avonmouth, specifically for future growth.

Q. You’ve recently installed new modular moving bed bioreactors at your Thornford water recycling centre. How will this technology help to improve your services and how are you embracing new technologies with your investment plans?

Modular moving bed bioreactors provide an alternate approach to biological treatment by way of its modular approach and smaller footprint when compared to traditional concrete structure. It also offers the added benefit to add/reduce capacity at a later date. We are also trialing new tertiary solids removal processes to meet the increasingly tighter consents required under the WINEP, which will reduce even further in the future. We have been continuing to work in collaboration with other water companies to constantly trial new technologies with challenging targets for zinc within the next 10 years.