Interception of channel seepage using groundwater
pumping is usually undertaken by pumping from shallow bores placed
near the channel. The water intercepted by the pump can either
be transported and stored off-site or returned directly into
the channel. Groundwater pumping to reduce channel seepage is
an extremely expensive option due to operation and maintenance
costs, and is therefore not commonly used a water-saving measure.
However, in cases when the channel seepage is causing accessions
to the and localised salinity problems, groundwater pumping can
become an economical alternative.
Interception of water seeping from the channel requires installation
of a pipe collection system, pumps and conveyance pipeline to
a suitable disposal site, or where quality is not an issue, back
into the channel. Investigations are required to establish the
details and costs of necessary work, which are specific for each
channel. Capital and operating costs for interception and disposal
works are relatively high compared to the various other means
of seepage control. Availability of a suitable disposal site
is also an important issue and this could be critical if the
channel seepage becomes mixed with saline groundwater (Sinclair
Knight Merz, 1998).
