WIREDGOV

Lockdown during the Covid-19 pandemic has brought many changes and challenges to life in the UK. Government guidance aimed to contain and reduce virus transmission has reshaped our day-to-day lives, from how much electricity we use, to the way we consume water.

Over the last few months, teams at the Met Office have been working with water companies to help identify the changes and trends in water use brought about during lockdown.

Before and after lockdown

Our teams compared water use before lockdown (February to early March) and at the beginning of lockdown (late March to early April).  As can be seen in Figure 1 below, most water companies have seen an increase in average water consumption during lockdown, with companies covering predominantly suburban areas (G and H) seeing the most noticeable increase, whereas companies operating in city areas see a reduction in water use (A).  The data also showed differences between weekday and weekend water consumption largely disappeared.

Figure 1) Percentage change in daily average base water consumption for ten water companies in early lockdown (late March-early April) compared to before lockdown (February-early March)

Lockdown during March and May coincided with a prolonged spell of sunny, warm and very dry weather, which introduced a ‘fine spring weekend’ effect to every day.  The data suggests water use during this period is more sensitive to weather compared to pre-lockdown, with weather the main driver of day-to-day variations.  For example, an increase in temperature appears to cause a higher rise in water demand than it would pre-lockdown.  Figure 2 below shows an inexorable rise in water use to around 30% above base usage by late May, similar to the peak levels seen during the hot summer of July 2018.

Figure 2) Percentage change in daily water consumption from average during lockdown. 

“Lots of us are spending more time at home and along with warm weather we’ve seen customers using water differently”, said David Hinton, Chief Executive at South East Water.  “Increased demand for tap water in our area is more akin to patterns we see in an exceptionally hot summer.  More water is being used on DIY projects and gardening which is contributing to the additional 25% of water we’re treating and pumping through our water distribution system.”

Working together to help keep taps flowing

Water demand models do not currently take into account these new water use patterns observed during lockdown.   This has created new operational challenges for water companies, who despite having sufficient water supply in their reservoirs, are unable to treat and pump water fast enough to meet the unexpectedly high demand at peak times.

“By working together with water companies and sharing experiences, we can more accurately analyse the effect of lockdown on water use”, said Nick Law, Senior Account Manager at the Met Office.  “From this the Met Office has produced a ‘COVID’ sensitive model that our colleagues in the water companies involved in this research can use to adjust their demand planning and better anticipate water usage as this new way of life continues.”

What can be done to better prepare for the future?

This year’s summer months may bring particular challenges to water companies, as normal population movements during summer holidays are impacted by Covid-19 restrictions.  Water companies that normally experience a noticeable drop in water use during holidays could experience an increase in water demand, due to a combination of lockdown and spells of warm summer weather.

“The challenge now is to understand how peak Summer demand levels can be forecast and managed, to ensure supplies can be maintained” said Ian Savage, Strategic Control Manager at Thames Water. 

Based on modelling during lockdown so far, the Met Office can perform scenario planning for an extended period of lockdown for different weather types in July and August. This will allow the water industry to better anticipate water demand during periods of lockdown restrictions and plan for different weather scenarios, as this new way of life continues.

 Want to find out more? 

If you’re interested in learning more about how we’re helping the water industry forecast and manage water demand, check out our recent article published in Utility Week.