News release
5 May 2008
Wet weather breaks drought for most
Above average rainfall this April has boosted river flows, aquifers and soil moisture levels, effectively breaking
summer’s drought in most parts of the region.
Greater Wellington's monthly hydrological summary for April shows that overall rainfall totals for the month in the west
of the region were 150% to double the long-term averages.
But the eastern Wairarapa hill country has remained drier than usual with our monitoring site ‘Tanawa Hut’ receiving
only half of its long term rainfall average for the year to date.
The main feature of the month was a northerly downpour early on the 30th that triggered flood warning alert systems in
the Hutt and Waikanae rivers.
The downpour boosted April rainfall totals to 143mm for Greater Wellington’s Karori monitoring site and 138.5mm for
Waikanae, both well above average for the month.
The Wairarapa plains also enjoyed significant rains during April and rainfall totals for the year to date are now 80% of
average, up from about 60% at the end of March.
Although the rains boosted river flows significantly, most rivers still had below-average flows for April due to the
long-lasting effects of the extended dry spell.
However, aquifers recovered significantly due to more rainfall, lower evaporation and less irrigation.
Soil moisture levels also recovered significantly increasing almost to the pre-summer levels at Greater Wellington
monitoring sites on the Wairarapa plains. But the drier eastern hills need more rain to eliminate the moisture shortfall
from the dry summer.
This summary is based on data from selected monitoring locations in the Wellington region. Greater Wellington monitors
rainfall, river flows, groundwater levels and soil moisture at many locations that may not be mentioned in this summary
report. Maps of site locations and up-to-date data can be found at www.gw.govt.nz/monitoring
ENDS