Water in Whisky Making: Does the Source Matter?

In August 2021, Pulteney in Wick paused production because prolonged dry weather had left Loch Hempriggs, the source feeding its lade, extremely low. The subsequent report quoted the company describing a voluntary pause to protect the loch.[6] For a distillery, water is more than a picturesque spring on a label. An unreliable supply can interrupt whisky making.

Its influence on character is a more intricate story. The Scotch Whisky Technical File places water alongside fermentation and distillation, while bourbon producers show how both a distillery’s own lake and treated municipal water can serve the work.[1][5]

Where water enters whisky making

Water works throughout a distillery: moistening grain, extracting its contents, cooling spirit vapour back into liquid, cleaning equipment and adjusting alcoholic strength.[1][2][3] Only some of that water becomes part of the spirit.

The distinction is essential. Water mixed with grain is production material; water cooling a condenser has a separate job. A claim about a distillery’s source becomes much more revealing when it tells you where that water is used.

A distillery’s total water use therefore tells a different story from the amount entering its spirit. The Scotch Whisky Association, an industry body, says water use varies with distillery capacity and location.[3]

For the wider ingredients picture, start with the three ingredients of Scotch malt whisky. Water belongs there, but it also runs through the less visible business of keeping equipment working and production supplied.

What the source can tell you

Water carries the influence of the ground it crosses. The Scotch Technical File connects differences between distillery waters with their rocks and countryside: peaty water from moorland, soft water associated with granite and hard water associated with sandstone all feature in its account of Scotch production.[1]

There is no single winning description here. The Technical File recognises different sources rather than prescribing one desirable water character for every distillery. Nor should peaty water be confused with the source of smoky malt: peat smoke reaches malt during kilning.[1]

Dependability has helped shape the distillery map. The same document says Scotch distilleries have historically been built where a reliable supply of water of a particular quality was available. Distilleries frequently own their sources to secure continuity of supply.[1]

A spring’s name is therefore the beginning of the story. Its characteristics matter, as does the ability to keep drawing suitable water from it. The source supplies an ingredient and sustains the practical demands of production.

Does good whisky need soft water?

Soft water is not the only kind recognised in Scotch production. A 1995 Scotch Whisky Association text said that good, soft water was essential to a distillery; the later Scotch Technical File includes hard, soft and peaty waters in its account of mashing and fermentation water.[1] Those accounts disagree, without establishing that one source makes better whisky.

Glenmorangie offers a striking producer example. The distillery describes Tarlogie Springs as unusually rich in minerals and says it owns and protects the surrounding forest.[4] Its account shows how one producer characterises and safeguards its source, rather than providing an independent comparison of Scottish waters.

“Mineral-rich” is a description claimed for the water, not a ranking of the whisky. The quality claim would need evidence connecting that characteristic to a better result than another source could produce.

Water also shares the work of creating character. The Technical File places its contribution alongside fermentation, stills and the selection of spirit during distillation.[1] For another part of that chain, explore yeast and its effect on flavour.

What Kentucky accounts actually establish

A lake on distillery property and a municipal supply can both have a place in bourbon production. A 2013 Louisville Public Media report found Maker’s Mark drawing from its own lake without treating the raw water, while Old Forester used Louisville Water Company water, with reverse osmosis treatment before bottling.[5]

The distillers differed on the importance of limestone water. Maker’s Mark’s Greg Davis called it “a key ingredient”; Brown-Forman’s Chris Morris said it was “not essential”.[5] These are distinct, attributed production perspectives, rather than equivalent scientific findings.

The revealing question is what each producer needs its water to do, and how it prepares it for that purpose. The report records different approaches, not a single indispensable type of supply.

The claim that Kentucky’s iron-free limestone water is the secret of bourbon belongs to legend. The report cites no study for its limestone chemistry claims, and geologist Alan Fryar said limestone water was what was available locally, rather than an indispensable ingredient.[5]

Keep the source separate from the explanation attached to it. A lake or municipal supplier can be documented directly; establishing exactly what its water contributes to the spirit calls for different evidence.

Water before the cask and before bottling

Water used to adjust Scotch whisky’s strength need not arrive unchanged from the source. The Technical File describes potable water that may be purified, including by distillation, demineralisation or reverse osmosis.[1]

It also describes new make spirit, the spirit before maturation, as normally diluted to somewhere between 60% and 70% ABV before entering cask.[1] That range records normal practice, rather than a single filling strength shared by every distillery.

This is another substantial role for water beyond the mash tun. A story confined to springs and grain misses the water added later to adjust strength, and any treatment used to prepare it for that task.

“Uses treated water” is consequently an incomplete criticism. Ask which water is treated, how it is treated and where it enters production. Suitability for the job matters more than whether the method sounds traditional.

When supply matters more than reputation

A production interruption is not a permanent change in a distillery’s status. What it reveals is the immediate constraint of supply: however suitable a source may usually be for whisky making, its reputation cannot make up for a shortage.

Research with The Glenlivet tackled that problem through the surrounding land. University of Aberdeen and James Hutton Institute researchers tested small dams designed to retain water during wet periods for use during dry ones. The university’s August 2022 account reported a “small but positive impact”.[7]

The same account noted that groundwater is typically colder than surface water in summer. It also recorded that the dry summer of 2018 depleted groundwater until the following spring.[7] Resilience depends on more than whether rain has fallen recently: the effects of a dry season can endure.

Scarcity can also reach beyond a single distillery’s source. A September 2025 press report recorded the Lower Spey and Berwickshire reaching SEPA’s highest scarcity alert, Significant Scarcity, triggering restrictions on water diverted from natural sources.[8]

What water stewardship measures

Water is a shared resource as well as a distillery input. The SWA’s Water Stewardship Framework, published on 10 July 2023, organised its approach around responsible use, engagement and collaboration, and advocacy.[3]

The announcement reported a 22% improvement in water efficiency since 2012. It also set out the industry’s 2025 target: 12.5 to 25 litres of water per litre of alcohol produced, depending on distillery size and output.[3]

The improvement records a reported change from a baseline; the target describes an intended level of use, not an achievement by every distillery. Neither figure measures the source water contained in a bottle.

How to assess a water claim

When a producer puts its source at the heart of the story, ask three questions:

1. The job: is the water used for mashing, cooling or strength adjustment?
2. The evidence: is this a producer’s account, a reported comment or a documented comparison?
3. The scope: does the evidence identify the source, or also demonstrate its effect on the spirit?

These questions leave plenty of room to appreciate a protected spring without making it explain an entire whisky. They also give treated municipal water a fair hearing. The meaningful comparison is about suitability, preparation and dependable supply, not which source makes the prettiest picture.

Where to go next

• The Three Ingredients of Scotch Malt Whisky: put water alongside the other raw materials.
• Barley Varieties and Why They Matter: examine another ingredient claim.
• Yeast and Its Effect on Flavour: follow fermentation’s part in the story.

Sources

[1] UK Government, Defra. Technical File for Scotch Whisky, June 2019. https://assets.publishing.service.gov.uk/media/5fd36667e90e07662ed92c85/Scotch_Whisky_Technical_File_-_June_2019.pdf

[2] The Maltsters’ Association of Great Britain. How Malt is Made, undated web edition. https://www.ukmalt.com/uk-malting-industry/how-malt-is-made/

[3] Scotch Whisky Association. Whisky industry launches water stewardship framework, 10 July 2023. https://scotch-whisky.org.uk/newsroom/whisky-industry-launches-water-stewardship-framework/

[4] Glenmorangie. Members, “Our protected water source”, undated web edition, producer’s account. https://www.glenmorangie.com/en-us/pages/members

[5] Louisville Public Media, Erica Peterson. Is Kentucky Limestone Water Indispensible for Bourbon?, 27 November 2013. https://lpm.org/news/2013-11-27/is-kentucky-limestone-water-indispensible-for-bourbon

[6] John O’Groat Journal. Pause to production will have negligible impact on future, 10 September 2021. https://www.johnogroat-journal.co.uk/news/pause-to-production-will-have-negligible-impact-on-future-250648

[7] University of Aberdeen. A dam fine dram: researchers team up with The Glenlivet to protect whisky production, 1 August 2022. https://www.abdn.ac.uk/geosciences/news/16226/

[8] Scottish Business News. Water restrictions expanded to distillery heartlands as Scottish rivers reach crisis point, 2 September 2025. https://scottishbusinessnews.net/water-restrictions-expanded-to-distillery-heartlands-as-scottish-rivers-reach-crisis-point/

This desk-researched article uses the supplied verified fact sheet, distinguishing technical documentation, producer accounts, institutional research summaries and press reporting.

Last checked: November 2026