How water companies can optimise CAPEX without impacting performance
Water companies are under pressure to deliver better environmental and service outcomes while keeping capital investment under close control. Under AMP-8, this pressure is especially visible in wastewater planning, where companies need to reduce spills, manage growth, improve resilience and justify investment decisions with clear evidence.
For senior technical decision-makers, the challenge is practical. A scheme needs to solve the problem it was designed for, satisfy regulatory expectations and represent good value for customers. That means capital efficiency cannot be assessed through cost alone. A lower-cost option only has value if it maintains the required level of service and remains defensible when tested against future conditions.
Optimisation technology gives water companies a structured way to compare design alternatives, understand cost-performance trade-offs and select interventions with greater confidence.
Why CAPEX decisions become difficult in wastewater planning
Wastewater networks are interconnected systems. An intervention in one part of a catchment can affect performance elsewhere. A storage scheme may reduce spill frequency at one location while increasing downstream pressure. A pipe upgrade may improve conveyance locally while revealing another constraint further through the network.
This makes capital expenditure (CAPEX) planning difficult when options are assessed one at a time. Traditional modelling methods often produce a single candidate solution, which is then costed, reviewed and tested by wider project teams. If the cost is too high, the benefit is too limited or the scheme creates issues elsewhere, the option may be passed back for another round of modelling.
That design churn carries cost. It uses modeller time, delays decisions and creates uncertainty for capital planning teams. It also makes it harder to demonstrate that the selected scheme represents the best available use of investment.
Compare a range of costed options
A stronger approach is to compare many costed intervention combinations before committing to a preferred scheme. Optimisation technology allows modelling teams to define the problem, set objectives and constraints, and explore a large design space systematically. This can include options such as:
- Pipe upgrades
- Pump upgrades
- Storage
- Flow controls
- Real-time control strategies
- SuDS and surface water separation
- Strategic diversions or catchment-level interventions
The value comes from assessing how these options perform in combination. Some interventions may deliver strong benefits in isolation but add limited value when paired with other upgrades. Others may appear modest on their own but become important as part of a wider catchment strategy.
By testing combinations systematically, teams can identify which options deliver the strongest performance for the available budget.
Understand cost-performance trade-offs
Capital optimisation should give decision-makers a clear view of trade-offs. Instead of asking whether one scheme is acceptable, teams can compare a range of strong options at different investment levels. This helps answer important planning questions:
- What level of performance can be achieved for a given budget?
- Where does additional spend create meaningful improvement?
- Where do diminishing returns begin?
- Which interventions appear consistently in high-performing designs?
- Which options become less valuable once wider catchment effects are considered?
These questions matter because regulatory and internal governance processes increasingly require clear justification. A preferred scheme needs to be supported by evidence showing why it was selected and how it compares with realistic alternatives.
A cost-performance view also helps senior leaders make decisions that reflect both engineering and commercial priorities. The cheapest design may leave too much performance risk. The highest-performing design may exceed the level of investment needed to meet service and compliance requirements. The strongest option is often the one that gives the right balance of cost, performance, resilience and deliverability.
Maintain service and compliance standards
Optimising CAPEX should not weaken service outcomes. The process needs to include the constraints that matter to the organisation, the regulator and the community served by the network. These may include:
- Spill frequency or spill volume targets
- Flood risk reduction
- Level of service expectations
- Future growth allowances
- Climate change scenarios
- Asset constraints
- Buildability and operational limitations
By setting these constraints at the start, optimisation technology can focus on solutions that meet defined performance requirements. This helps avoid low-cost options that appear attractive commercially but fail to provide the required standard of service.
It also supports regulatory confidence. When a water company can show that a selected option was tested against defined objectives, constraints and future scenarios, the investment case becomes stronger.
Reduce unexplored value
One of the largest hidden costs in capital planning is uncertainty. Manual methods can produce workable designs, but they often leave teams unsure whether better cost-performance combinations remain unexplored.
Optimisation reduces this uncertainty by searching the design space more systematically. The aim is to give decision-makers confidence that the preferred option sits among the strongest available choices, rather than being the first workable design found within the available time.
This does not remove the need for engineering judgement. Senior modellers and technical leads remain essential in defining the problem, setting realistic boundaries, reviewing results and deciding which options should move forward. The technology expands the evidence base they use to make those decisions.
A clearer route to capital efficiency
For water companies, CAPEX efficiency depends on selecting interventions that deliver the required performance at a defensible cost. That requires a structured way to compare alternatives, understand trade-offs and demonstrate why chosen schemes represent good value.
HEEDS, implemented with STRIDE’s water-sector expertise and API integration, supports this process by enabling optimisation-led assessment of costed design alternatives. It helps teams explore intervention combinations systematically, identify high-performing options and produce structured outputs that support internal governance and regulatory review.
For senior technical decision-makers, the result is a clearer route to capital efficiency: stronger evidence, fewer unexplored options and greater confidence that investment decisions maintain service and compliance standards.
