Scottish Water has set out a final business plan for 2027–2033 (SR27) that proposes £13.4bn of funding over the next six years, with a strong emphasis on asset maintenance and resilience in the face of climate change, ageing infrastructure and shifting population patterns.

The publicly owned company says the package will be used to “protect and improve” water and wastewater services across Scotland. The plan now goes to the Water Industry Commission for Scotland (WICS) for scrutiny and public consultation before final decisions are made on investment levels and customer charges.

What the plan contains

Of the proposed £13.4bn, Scottish Water allocates about £8.1bn to capital expenditure on pipes, treatment works and related infrastructure, with the remaining £5.3bn earmarked for operating and essential service costs. The utility says the capital figure is £400M lower than the draft plan published last year, reflecting customer feedback seeking to keep bills as affordable as possible.

A central theme of the plan is asset management. Scottish Water says it manages an asset base that would cost nearly £122bn to replace in full, ranging from century-old pipelines and large treatment works to digital monitoring equipment. Many assets date from major infrastructure programmes of the mid-20th century and the 1990s, while more recent, more complex installations often have shorter lifespans and need more frequent replacement.

The company proposes to increase asset maintenance spending by about 24% compared with the 2021–27 period (SR21). Its asset repair, refurbishment and replacement policy (AR3) will prioritise repairing and refurbishing existing assets before replacing them, with the stated aim of extending useful asset life and achieving value for money.

Detailed allocations include:

Scottish Water highlights particular asset risks and projects. For example, it intends to invest in the Invercannie Aqueduct, a 28km structure built in 1924 that supplies around 130,000 properties; groundwater ingress into the aqueduct has raised water-quality concerns. The plan also commits to replacing ageing asbestos cement pipes, addressing reservoir safety issues flagged by engineers, and expanding monitoring of intermittent discharges from networks and treatment works.

Climate, nature-based solutions and land management

Climate change underpins much of the company’s rationale for the plan. Scottish Water says customers explicitly prioritised investment to protect infrastructure from extreme weather and to adopt innovative, long-term adaptation approaches. The plan includes continued investment in peatland restoration, woodland creation and catchment management intended to reduce runoff and protect water quality; the Loch Katrine land‑management programme is cited as a significant ongoing example, with more than 50ha of peatland already restored since January 2025.

Developers, housing growth and capacity

The plan sets out how Scottish Water intends to fund capacity for new homes and commercial connections. It proposes £551M to provide water and wastewater capacity to facilitate roughly 20,000 new homes and business connections a year, funded in part through infrastructure charges levied on developers. The company says it will incentivise water-efficient and sustainable drainage designs (SuDS and blue‑green infrastructure) to reduce the need for upstream asset enhancements.

Workforce and operational resilience

To deliver the programme, Scottish Water plans investments in skills and training, including proposals for a new training centre and a strategic workforce plan to ensure it has the right mix of staff. The business plan also signals a review of operational working patterns and resilience arrangements, including considerations around 24/7 service provision and greater use of digital asset management.

Regulatory process and next steps

The Water Industry Commission for Scotland will review the plan and consult on the proposed package, including the impact on customer bills. Final charges and confirmed funding levels will be set following that process. Scottish Water’s focus on AR3 maintenance and targeted enhancements will be considered alongside regulators’ priorities on water quality and environmental performance.

The plan arrives against a backdrop of mounting cost pressures across the utilities sector and increasing regulatory and environmental expectations. Scottish Water’s approach – prioritising maintenance and selective enhancement while tempering capital spending from earlier proposals – reflects the tension between minimising bill rises and addressing long‑standing infrastructure deficits and climate risks.

WICS will publish its Draft Determination in June and its Final Determination in October 2026, confirming investment levels and customer charges for 2027–2033. Ahead of the new period, Scottish Water will publish a detailed Delivery Plan setting out what customers can expect.

Alex Plant, chief executive of Scottish Water, said: “This plan sets out how we can continue to provide high quality, reliable water and wastewater services for Scotland, while keeping customer bills as low as possible.

“More than 25,000 people helped shape this plan, and their message was clear – protect essential services, invest for the future, but do so in a way that is fair and affordable.

“Scottish Water’s charges are among the lowest of any water utility in the UK and, as a publicly owned business, every penny we receive is re‑invested in services for our customers.

“These have been tough choices, but we are confident the plan strikes the right balance for customers, communities and the environment.”

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