Seafield WwTW Investment

Short Term Investment

Scottish Water, Stirling Water and Veolia are implementing recommendations from the 2018 independent Seafield Strategic Odour Review which was originally commissioned by Scottish Water and carried out by the Wood Group. One of the recommendations made by the Wood Group was to investigate options aimed at minimising sludge storage in the primary settlement tanks (PSTs). 

Since the stakeholder group last met in January, Scottish Water’s consultants (M2) have now completed their investigation of options, and, together with Scottish Water and Stirling Water, have identified a number of additional projects aimed at delivering improvements to primary tank sludge storage. Overall, these projects are designed to reduce the risk of sludge being held back in the primary settlement tanks (PSTs) by providing additional capacity. These improvements are:

• additional storage to deal with extra sludge from the PST’s during periods of “first flush” rainfall events, maintenance and unforeseen incidents/breakdowns
• additional sludge thickening and dewatering capacity to assist with managing peaks in sludge throughput from the PSTs and at the Sludge Treatment Centre (STC)

In addition, to improve sludge management and resilience in Edinburgh and the surrounding area, we are planning for the inclusion of a new sludge cake import facility at Seafield to provide improved operational flexibility and resilience to this operation.

Next Steps

As we said in January, Scottish Water is committed to delivering this investment in the next regulatory period which begins in April 2021. Therefore, to ensure that the project can be delivered early within this period, a start has been made to confirm the scope and progress it through our technical appraisal process.

In order to ensure value for money for our customers, Scottish Water operates a rigorous investment process. The planning phase is now complete with a preferred option identified (step 1 below). The next phase (step 2) is to complete the technical appraisal of the project which we anticipate will be in autumn this year. This will then enable us to develop outline design, obtain permissions and finalise contracts (step 3).

Long Term Investment

Based on current growth forecast, Seafield WWTW is expected to have sufficient capacity to serve the City of Edinburgh and the surrounding area until the 2030’s. As such, Scottish Water is at the very early stages of developing our thinking on what the long-term options may look like for Seafield beyond that date.

As outlined in January, Scottish Water is committed to developing these options with stakeholders from an early stage and we will aim to say more about this in the next stakeholder update.