Water and soil monitoring trends causes concern
2
5 Quay Street, P O Box 364, Whakatane, New
Zealand
Telephone: 0800 ENV BOP (368
267) Facsimile: 0800 ENV FAX (368 329)
Email:
info@envbop.govt.nz Website:
www.envbop.govt.nz
Pollution Hotline: 0800 73 83
93 International: +64 7 9223390
MEDIA
RELEASE
Water and soil quality monitoring
trends cause for concern
For immediate release: 18
December 2009
Latest water and soil quality
monitoring trends are giving Environment Bay of Plenty
councillors and staff major cause for
concern.
Regulation Monitoring Operations Committee
Chairman Malcolm Whitaker is urging his fellow councillors
to consider the impacts of increased nutrient leaching from
soil and its impacts on water quality over time as they
develop the next Regional Policy Statement.
“The
nutrient levels in soils aren’t so high at the moment that
they’re causing major problems but the increasing trends
will be significant over time, and that is of concern and
something we need to be factoring into our planning for the
region,” Councillor Whitaker said.
“The impetus
is on us to ensure the quality of water is maintained and
not degraded over time through land use.”
Latest
monitoring of dairy pasture and maize cropping sites
throughout the region showed an increase in the levels of
anaerobically mineralisable nitrogen and phosphorus in dairy
sites, which could potentially lead to increased pollution
of our water bodies.
Environment Bay of Plenty
Group Manager Water Management Eddie Grogan said the factors
causing the increasing trends are inextricably
linked.
“What goes onto the land ends up in our
groundwater systems, the shallower or more porous the
aquifers are the more likely it is that the groundwater will
be high in nutrients, leading to contamination of our lakes,
rivers and streams,” Mr Grogan said.
“Excess
nutrients on the land end up in our groundwater systems, and
while the deeper aquifer systems where we get our drinking
water from are well within the Ministry of Health’s
acceptable limits for nitrate-nitrogen levels, we cannot be
complacent. Monitoring showed high levels of
nitrate-nitrogen in shallower bores and near surface bores,
which is a direct link to land use, in particular dairying,
horticulture, agriculture and pastoral use,” Mr Grogan
said.
He said shallower groundwater with high
nitrate-nitrogen levels was more likely to pollute nearby
waterways – something the region can ill
afford.
“Yet another disturbing trend from the
latest monitoring is that at the same time the water quality
of many of our rivers and streams is deteriorating. The main
indicators of this are increases in nitrogen, bacteria and
suspended solids/turbidity – once again, notably in
catchments dominated by pastoral agriculture and
horticulture,” Mr Grogan said.
Of the 40 rivers
and stream sites monitored, 12 sites showed significant
increases in nitrogen and 15 sites showed significant
increases for the indicator bacteria Escherichia coli
(E-coli), which indicates faecal contamination and an
increased risk to people using waterways for recreation or
water supply.
Increasing turbidity (water
cloudiness) was also found in a range of Bay of Plenty
rivers and
streams.
ENDS.