In our recent blog, we discussed how a degradation plan differs from business as usual planning, outlining some of the benefits of having this capability rather than planning for every eventuality.

Borrowing from the Scottish poet Robert Burns ‘the best laid plans of mice and men oft go awry’. Whether it’s due to appliances breaking down; issues with the availability or a number of factors, Fire and Rescue Services regularly find themselves having to adapt plans to suit the current circumstances.

Since the publication of the original blog, a number of people have asked if we can share some of the detail behind the analysis. As such, we have built an anonymized version of the Degradation Planning tool allowing a greater degree of user interaction.

This has been achieved using real geographies and road networks within England but with adapted station names so as to illustrate the process. The locations within the tool have been optimised to maximise performance to the greatest proportion of the population within 20-mins.

What demand has been applied?

Using the population of the area as a proxy for demand allows for the application of high-level assumptions. Ideally, we would look to use a mix of Incident Demand and inherent risk within the county but it would be up to each individual service to decide on their demand inputs.

Why have you used a 20-min target?

The findings from the recent HMICFRS inspections found a lack of consistency in the targets applied by Fire and Rescue Services across England. In this example, our approach replicates spate conditions setting a 20-min target. This is a parameter that can be tailored to specific Fire and Rescue services, either by setting a general target level or applying specific response standards based on the geography (i.e. different targets for Urban, Town & Fringe  and Rural areas).

What travel times have you used?

The travel times within the model use ‘HERE’ road network creating a matrix from each Station to each LSOA (Lowest Super Output Areas). These timings reflect the average road speeds at 11am, consistent with the methodology used in our other tools.

What does the tool show?

The view below shows the key outputs from the Degradation Plan tool. Clicking on any of the bars on the top left-hand chart will select the optimal scenario with the relevant number of bases. For example, clicking on the 1-base solution will automatically update all of the other views and shows:

  • 21.4% of incidents would occur within a 20-minute response time of the optimal 1 base
  • The map on the top right shows this location to be Palmerston North with
    • Average response time of 34.1mins
    • Maximum response time of 89.3mins (to the extreme North-West of the county)
    • Ability to see the areas in/out of the response target
    • Ability to colour the map either by performance or by Catchment area (something that becomes more important when multiple bases are selected)
    • Hovering over any particular area (LSOA) will give a summary of the outputs for that area
  • The bottom left view provides some high-level statistics on this solution accounting for
    • Annual demand within the catchment and proportion of total
    • The amount of demand within target as a number and a percentage (Performance)
    • An estimation of the appliance utilisation and average response time.
  • The second map down on the right provides 10-min drive rings from the optimal station
  • The line chart on the bottom right shows the cumulative proportion of demand that sits within each response time.

Changing the view

By clicking to select a different bar, this will update each of the views, providing the analysis for a different solution.

As the number of bases increase stations are added that provide more coverage with the second station being placed in the South at Charleston; the third in the west in Jefferson City; the fourth in the North at Denver and the fifth in South-Central areas of Bismark.

Interestingly moving from a 5 to 6 base solution removes Denver and replaces with Halifax and Carson City as these selections give a higher overall performance. 

Bespoke Tool

A bespoke tool, shown in the dashboard below, has been developed to allow users to select their own stations and response threshold and understand the impact that this would have on coverage. By filtering stations on and off, it is possible to quickly determine the change in performance that decisions would have, while also demonstrating the key areas of risk.

The default display shows a 2 station solution with Palmerston North and Nashville selected. Using these stations 25.8% of incident would be within a 20-min response standard. This observed level substantially lower performance than the 39.5% seen in the optimal solution where the bases chosen were Palmerston North and Charleston. This suggests that although there is benefit in putting the second station towards the South of the county, Nashville would be too far to the South and limits coverage.


The Covid-19 epidemic has brought a greater focus on Resilience Modelling within Fire and Rescue Services. There is a need to combine the professional judgement of Fire Officers with to flexible analytical tools enable evidence based decision making. We hope that this article has helped to provide greater clarity of the degradation list and how it can be used.

For further information on our degradation list tool, please email