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Tullich WTW, Scotland

The £29 million Oban Tullich Water Treatment Works is one of Scottish Water’s biggest ever investments in Argyll and Bute. The population in Oban and the surrounding area of 12,000, more than doubles during the summer months to 40,000, due to the number of visiting tourists. The new water treatment works is providing cleaner, fresher, quality drinking water and will future proof supplies for more properties and development in the area for more than 20 years ahead.


Tullich WTW supplies drinking water to Oban in Argyll, Scotland. The works takes raw water from Loch Gleann A’Bhearraidh Reservoir and currently processes 7.2 million litres of water a day through its filtration system – the equivalent of around 7,200 baths. Working at full capacity, it has the ability to process 11.8 million litres a day.

Construction began on the site in Spring 2016 and the site has been operational since December 2018. It was delivered by Scottish Water’s delivery partner ESD (Efficient Service Delivery). ESD is a fully integrated joint venture between Black & Veatch, Galliford Try and MWH Treatment.

“This is a major investment in our water infrastructure in the Oban area which will safeguard a robust and resilient water supply for many years to come”

Jim Tudhope, Scottish Water’s Project Manager

Innovative approaches

Project Drivers

  • Aging asset built 1970 – aging technology
  • Changing raw water quality
  • THM failures
  • Vulnerability to cryptosporidium
  • Need for greater supply resilience
  • Negating use of ozone


Outline Solution

  • New inlet pumping station
  • Dissolved air flotation (DAF) plant
  • Primary and secondary rapid gravity filters
  • New MCC’s
  • Chemical dosing
  • Sludge treatment plant
  • New administration building and workshop

ESD Approach

ESD is a fully integrated joint venture between Black & Veatch, Galliford Try and MWH Treatment. Tullich was identified as a Conversion Project which we would use to accelerate the application of digital tools beyond digital engineering into the digital delivery space.


Optimised use of the digital tool-box

Our digital delivery platform brought a different way of thinking about project delivery by creating open dialogue between all the parties and a joined up approach to getting the best out of construction activities.


Visual Project Initiation

This gave the whole team an instant visual representation of what had to be built.


BIM 360 Glue

BIM360 Glue, a cloud based tool to share 3D models, allowed our supply chain to interface with the model and add their equipment. It was used for visualisation with Scottish Water making for optimised design development meetings as the 3D images mean you don’t need to be able to read complex 2D drawings to contribute.


BIM 360 Field

At Tullich, it has helped coordinate multiple contractors working on a relatively confined site and therefore minimised disruption. The collaborative approach ensures buy-in from all stakeholders, including the supply chain.

Synchro – 4D

This allowed the team to visually create the timed sequence for building the project. The visual planning tools help focus on challenges and create solutions in an easier format than traditional planning methods.


Collaborative Planning

With the digital optimisation of the project, the team were also able to engage in much more detailed collaborative planning.This allowed the constant contribution of client’s operators, designer, construction and the supply chain. In turn, this provided a more integrated design, build and operation solution.



An early efficiency driver was to maximise the DfMA (design for manufacture and assembly) element of the project scope. It was applied to over 80% of the MEICA scope including:

  • DAFs,
  • Primary Filters,
  • Secondary Filters,
  • Chemical Dosing,
  • Associated pipework, access platforms & steelwork and distribution channels.


“In the very beginning, to get buy in from my operators, ESD could show them how to run it, how to maintain it in the virtual world which was fantastic. It meant they could visualise things before it was even built.”

Ross Barclay, Argyll Mainland team leader with Scottish Water