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Payments for Ecosystem Services (PES) – PES pilot research projects - Bristol Avon Rivers Trust - NE0139

Project overview:
Bristol Avon Rivers Trust (BART) and Wessex Water (WW) have identified a novel Payment for Ecosystem Services (PES) approach to mitigate Water Framework Directive (WFD) phosphate (P) failures from treated sewage effluent, which will lead to multiple ecosystem service benefits, potential multiple market development and wide transferability.
To date, typical water company solutions to reducing P concentration in effluent discharge have been to install P stripping, by chemical dosing, typically with iron chloride or sulphate. This expensive, energy, transport and resource-intensive process increases solid waste output from the sewage treatment process and is ultimately unsustainable.
This project will evaluate the technical and economic options available, challenges to adoption, and the success criteria necessary, to develop a robust, transferable, multi-PES benefit approach to the issue. A collaborative stakeholder-led approach will inform and evaluate each step in the PES cycle. This will build capacity for key stakeholders to develop the PES process and transfer knowledge to wider beneficiaries.
An intermediary (BART) will bring together a principal seller (The Tortworth Estate, the landowner) and principal buyer (WW) to broker a win-win arrangement, whereby the seller will own and manage a multi-benefit, wetland based ecosystem. This option has been derived from earlier appraisals by the buyer, seller and intermediary. The major requirement of the system will be to strip P from the WW-owned Cromhall sewage treatment works (STW), which could then be available for re-cycling.
Cromhall STW discharges into the Tortworth Brook, which then flows through a commercial stillwater fishery on the Tortworth Estate. The Tortworth Brook is a tributary of the Little Avon in South Gloucestershire, which is failing WFD for P and is targeted for “Good Ecological Status” by 2027.
In addition to the buyer, seller and intermediary, the project will benefit from an experienced team drawn from private and research sectors. Engain is a multi-national and independent environmental consultancy that will guide on options and economic evaluation process, stakeholder engagement design and facilitation, ecosystems and human adaptation to climate change, and ecological and hydrological assessment. Bath Spa University’s Science department will provide technical and research expertise in evaluating baseline ecosystem functioning, impacts, mitigation and services. The team will be supported by the unmatched constructed wetland technical expertise of Robert McInnes (RM Wetlands and Environment).
Wessex water have pledged to contribute £25,000 towards the project costs and to provide water sampling and laboratory services and technical expertise.
The preferred option has the potential to provide additional ecosystem services such as:
• Climate change mitigation from;
o avoidance of energy consumption in traditional P stripping process
o biomass fuel production for use on the Tortworth Estate
o potential displacement of inorganic fertiliser by the periodic spreading of P rich material accumulated within the wetland and;
o sequestration of carbon within the wetland
• Local habitat and biodiversity improvements, which could have quantifiable value to the RSPB, Gloucestershire Wildlife Trust and the Tortworth Estate, via increased visitor interest
• Increased value of the commercial fishery, by reduced stocking mortality from poor water quality

This project represents the first example of a multi-benefit PES approach to mitigating the impacts of sewage. The findings will help deliver the Natural Environment White Paper, contribute to WFD compliance and lead the way for a new, multi-benefit approach to P removal from municipal wastewater.
2.2 Objectives

To develop a robust and transferable approach to identifying and establishing a multi-benefit PES market, specifically related to sustainably reducing P discharges from sewage treatment works.
The objectives of the project are set against those of DEFRA and the PES scheme in the attached table
1. To develop a workable basis for a PES scheme and a preferred way forward, with buy-in from beneficiaries & suppliers.
2. To provide a collaborative learning approach and capacity building for the stake/shareholders and wider interested community
3. To identify and evaluate the PES opportunities, risks, values, challenges particularly for potential markets.
4. To produce a preferred option, based on sustainability criteria, for a solution to a known water quality issue within the Little Avon catchment.
5. To evaluate the key criteria required to make the concept transferable and the barriers to be overcome, and report how the findings/approach can be applied elsewhere, i.e. transferability after project life.

Project Documents
• FRP - Final Report : Final Report - Tortworth Brook Project   (15305k)
Time-Scale and Cost
From: 2012

To: 2013

Cost: £44,432
Contractor / Funded Organisations
Bath Spa University, Engain: Environmental Gain Ltd, Bristol Avon Rivers Trust
Economic Research              
Ecosystem Service