Chapter 9: Road drainage and the water environment

6 Residual Risks
The level of flood risk to the M1 Junction 19 has been investigated at an
appropriate level of detail. Suitable mitigation measures have been identified for
these risks.
Consequently, the flood risk to the development, if the recommended mitigation
measures are followed, will be low.
However, there is always a residual risk that an event will occur that exceeds the
design criteria.
Table 11 identifies what are considered to be the residual risks to the site:
Risk Impacts Potential Further
Mitigation Measures
Extreme rainfall event
greater than drainage
system design event.
Failure of to maintain
artificial drainage
systems (i.e. highway
drainage, land drains).
Failure of 3 rd parties to
maintain essential
infrastructure (i.e.
reservoirs, water supply
network).
• Water build up on
highway
• Water built up on
highways
• Impounding of water
against highway
embankment
• Water flow along
highways
• Consider alternative
drainage routes
based on road
camber/topography
only
• Consider alternative
drainage routes
based on
road/camber
topography only
• Regular inspection of
culverts,
implementation of
trash screens
• Pursue Severn Trent
for more details of
their assets in the
area, including
Stamford reservoir
upstream of scheme
and potential water
supply pipes which
run through the site
Table 11: Potential residual risks to site
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