DCC published its 3rd Local Aggregate Assessment shortly before Christmas. This is an annual document required by the NPPF "to provide a rolling evidence base to inform the approach to be taken in the Local Plans of the individual Mineral Planning Authorities to the supply of aggregates".
This LAA puts Devon's permitted reserves of land-won sand and gravel at the end of 2013 at 8.53 million tonnes, adjusted upwards from 8.14 million tonnes (to include a small reserve located in Somerset) giving a landbank of 13.8 years - using the ten year average sales of 0.62 million tonnes per year.
Changes are made to the LAA each year, changes that are not helpfully highlighted or contained in a table of modifications at the start of the document, changes that are not merely of a factual nature, changes that are not debated or ratified by councillors. One such change this year is how that figure of 13.8 years is calculated, more specifically how the ten year average of 0.62 million tonnes is calculated. The draft for the first LAA was put out for consultation beyond the mineral industry and other mineral planning authorities; subsequent LAAs were not. The consultation for the first LAA asked:
Do you support the use of weighted 10 year averages as a more responsive indicator than a simple 10 year average of sales data?
We answered "Yes" - the use of a weighted average was, after all, our suggestion.
A weighted average produces a more relevant, more responsive landbank figure by giving less weighting to out of date figures, more weighting to recent figures; for the last 5 years, sand and gravel usage has been less than half a million tonnes per annum, 10 years ago it was almost double that. Of course, the minerals industry, in the form of Devon Stone Federation et al., disliked the move to a more meaningful number, and said "No". To its credit, DCC stuck with the new calculation in its first and second LAA.
However, DCC has now reverted back to the simple average following discussions with the South West Aggregates Working Party, a group of minerals industry and planning representatives, but without any wider consultation; the Devon Stone Federation for one "is very pleased to see that the weighted average has been dropped". "Pleased"? Because the weighted average would indicate a landbank of sand and gravel in Devon of 15.8 years; the NPPF looks for at least seven years.
But the Devon Stone Federation and others may be less pleased in the future if sand and gravel sales take off, and the landbank remains stubbornly high by relying on the unweighted inclusion of low and outdated data; a weighted average would have highlighted resource shortages sooner.
