The approval of plans and projects - Transport Policy and Planning in Great Britain - page 379

Entry stage, is therefore the sum of the two and is known as the Approved Scheme
Cost (ASC).
If the estimated total cost of the scheme rises above the ASC the Department
may require a reappraisal to determine the value for money of the scheme, as
well as a consideration of lower cost alternatives. If the Department decides that
the scheme can proceed at a higher cost than the original ASC the Department
would, in all but exceptional circumstances, expect the local authority to fund
100% of the increase beyond that amount.
(ibid. para 2.7.19)
These provisions are illustrated in Figure 22.1. They represent a significant tightening
of previous arrangements and can place a local authority in an extremely difficult
position if unexpected cost increases (or a reduction or withdrawal of contributions
from other parties) occur at a late stage. It is then faced with either finding 100%
of the increase beyond the ASC (or making good shortfalls in other contributions)
or abandoning at the final hurdle a scheme which will have been planned for, and
resources committed to, over many years.