Water - Investment Planning and Prioritisation Group (IPPG) report: quarter 2 2022 to 2023

This report sets out how Scottish Water is progressing in developing interventions to address the needs on the ‘Development List’ up to the end of December 2022 (quarter 2 2022 to 2023).


4. Progress of the development of interventions with Level 1 and 2 appraisals

The purpose of this section is to provide:

  • An overview of the progress of interventions in Q2 that are subject to Level 1 and 2 appraisals
  • Highlights from significant Level 1 or 2 project investment appraisals completed in the last quarter
  • A review of lessons learnt from the delivery of PIA forecast in the last quarter and a look ahead to the next quarter.
  • The full list of interventions with Level 1 and 2 appraisals, with an indication of the anticipated timing, is shown in Appendix C, which is an additional document to this paper.

Quarterly review of progress of appraisals

Good progress has been made in project level decision making within Q2:

  • 16 project investment appraisals stages were completed within the quarter. This includes the additions to the forecast in the quarter (15% of the initial demand).
  • 15 of the 16 projects progressed through first time at the Investment Group/Investment Approval Group. These projects had a value of c.£190m.
  • A session with the Independent Customer Group (ICG) was held on 29th September. The feedback at the session was positive on the progress made to date in the development of the PIA, and the joint approach to the session by the PIA team and Corporate Affairs.
  • A positive session with Consumer Scotland held with the purpose of providing an update on the progress of PIA development within FY22/23 and to seek to understand any further expectations.
  • Project investment appraisal documents continue to be shared with stakeholders at Stage 3a (preferred option) and Stage 4 (Commitment).

Highlights from project investment appraisals completed within the quarter are shown below.

Project Investment Appraisal Highlights

Dunside reservoir Stage 3a Aug-22

Project on a non-operational reservoir that has investment needs for matters in the interests of safety.

The appraisal considered the resilience requirements due to the impact of climate change and assessed the community use of the asset. We plan to breach the reservoir and planting trees in the land space available. This removes an asset which would have ongoing liabilities and maintenance requirements, and turns it into a carbon sequestration opportunity, returning the land to a natural state and contributing to our net zero target. The PIA has been shared.

Erskine WwTW Stage 3a Sept-22

There were 21 strategic needs previously identified in the Erskine catchment. A system strategy is being developed to ensure these long-term needs are addressed optimally. Whilst this system strategy is developed, a tactical solution is required for Erskine WwTW to enable short-term growth and maintain compliance with the Controlled Activities Regulations (CAR) licence requirements. This appraisal considers the tactical needs only to a nominal horizon of 2026 to enable forecast short-term growth which exceeds the design capacity of the WwTW by c.70%.

The recommended intervention for Erskine WwTW will restore the health and safety risk for operating the site to an acceptable level, restore operation of failed assets, can be constructed offline from the existing process reducing complexity, brings the WwTW into compliance with technical standards for primary treatment, meets the requirement for short term growth as well as recovers primary sludge for future digestion. The option is a least regrets approach. The PIA has been shared.

Udny Green WwTW Stage 4 Sept-22

The WwTW has had a number of consent failures. To reduce the risk of compliance failure, a temporary chemical dosing system has been in use since 2018. There is no capacity to treat any additional load and flow due to growth. The Stage 4 PIA confirmed that constructing a new WwTW on the adjacent land is the best intervention option to be implemented. The PIA has been shared.

A review of lessons learnt from the delivery of PIA forecast in the last quarter

An overview of the appraisals at Stage 2/3/4 that were forecast to be delivered during Q2 2022/23 and the appraisals delivered is shown in Table 1.

The purpose of Table 1 is to provide internal visibility to enable forward planning for Level 1 and 2 interventions and to ensure enough work is being appraised to support the investment programme. It is not intended to be a fixed set of dates and the dates presented are the earliest that those will be achieved. A target of c.50% of milestones to be achieved is targeted due to the dynamic nature of the programme. 16 PIA Stages or 41% of the initial forecast were completed up from 36% in the previous quarter.

For example:

  • The projects are subject to reprioritisation in a dynamic programme
  • Dates have been reforecast to take into account lessons learnt from previous project investment appraisals, recosting of scopes and alternative options
  • The dates are set to align with our challenge of achieving 50% less time to start on site, which results in ambitious milestone forecasts
  • Some PIAs will require iterating after senior review at the Investment Group, which can have knock-on impacts on the rest of the programme.

There are three main themes driving the missed forecasts:

  • Repriorisation due to workload. This affected 23% (9) of the projects which had forecasts adjusted to the following quarters in line with the dynamic programme. Projects which were prioritised include Daer WTW and Bradan WTW.
  • Confirmation of scope & costing. This affected 18% (7) of the forecast projects.
  • o In a demonstration of the PIA approach driving the best value decision, cost escalations for the preferred option have driven costing of alternative options (Eela Water WTW Stage 3b) or rescoping options (Kirk Yetholm WwTW Stage 3a).
  • Further investigation required. This affected 10% (4) of the initial projects.
Table 1: Appraisal at Stage 3a/b and 4 anticipated for Q2 compared to actuals
Appraisal Portfolio
Stage Water Wastewater Other
  Jun-22 forecast Oct-22 actual Jun-22 forecast Oct-22 actual Jun-22 forecast Oct-22 actual
Stage 2: Strategic Optioneering Review (G40) 6 2 3 1 0 0
Stage 3a: Outline Investment Appraisal (G50) 6 2 10 3 0 0
Stage 3b: Outline Project Appraisal (G70) 6 2 3 3 0 0
Stage 4: Project Appraisal for Commitment (G80/90) 0 0 3 1 2 2

Projects reforecast by 12 months

In line with the dynamic programme a small number of projects have been reforecast by >12 months since the baseline forecast in April 2022. These are listed in Table 2 with the known consequences explained.

Table 2: Projects reforecast by >12 months
Project Name PIA Stage G40 Original forecast dates (Apr 22) G40 Current dates (Nov 22) Reason for the movement
5032240000 Philipshill WwTW Stage 2 Nov-22 Oct-23 One Planet Choices consideration and future licence requirements
Consequence
Risk to completion on site to meet developer build out rate. Temporary treatment may be required if the developer build out rate exceeds the site's capacity and the trade effluent consent is fully utilised.
Project Name PIA Stage G40 Original forecast dates (Apr 22) G40 Current dates (Nov 22) Reason for the movement
5037590000 Liberton Trunk Mains Stage 2 G40 (stage 2) was initially forecasted in SR15, before commencement of IAs Mar-23 Delay to non-destructive testing (NDT) surveys results
Consequence
The results from the NDT surveys will inform the extent of the Need. There is a chance that there is no Need (if NDTs show asset does not qualify for promotion under the MA025). Initial need was raised as between 2012 and 2016 there were over 60 bursts in the Liberton Trunk Mains (TMs) and associated distribution mains attributed to the Alnwickhill PRVs. Since the PRV replacement in 2017 there have been no bursts. There are 4 mains downstream of the PRVs that are cross connected and run as one network. Although all the bursts can be attributed to the performance of the PRVs, work is being carried out by Scottish Water to understand if the mains present a security of supply risk.

Forecast for remainder of 22/23

The forecast for 22/23 is shown below (Table 3) and the details are provided here

Table 3: Forecast of project appraisals at each gateway to be delivered during the following quarters of 22/23

Contact

Email: waterindustry@gov.scot

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