ABSTRACT
In 1971 domestic insurance cover in England was extended to include damage to household dwellings from subsidence (DoE, 1991). A few years later, England experienced its worst drought on record with the hot, dry summers of 1975 and 1976, separated by an unusually dry winter (Doornkamp et al., 1980; Doornkamp, 1993; an overview of summer drought from 1961 to 1990 is presented by Brignall et al., 1996a). Soil moisture loss and consequent shrinkage and subsidence in clay-rich soils resulted in numerous insurance claims: one subsidence claim was lodged per 1,000 dwellings in England and Wales for this 18-month period at a cost of £100 million to the insurance industry (Doornkamp, 1993). By 1979, subsidence claims comprised 10 per cent of the cost of all household insurance claims. Such claims have continued to mount in recent years, with 133 per cent more claims being submitted in the first quarter of 1996 than for the same period the previous year (Property Weekly, 1996). Figure 3.1 illustrates the dramatic increase in the cost of domestic subsidence claims in England. Subsidence now follows windstorms as the second most expensive ‘natural hazard’ affecting the insurance industry in the UK (Chartered Insurance Institute Society of Fellows Study Group, 1994).
