Thursday, August 27, 2009

Choose - cows or rivers

Manawatu river

an interesting report on these waters

"If the Manawatu River were a person, it would be "morbidly obese".

Massey University ecologist and water quality campaigner Mike Joy made the comparison yesterday, after water-quality results from Horizons Regional Council showed the Manawatu River was the most polluted river in the region."

from the report



Generally Poor. There is little forested area in the headwaters to contribute to pristine water quality and water is significantly degraded as the river flows from the east to the west coast. When the river is at high flows, levels of E. coli, sediment and nutrients are elevated.


Good, significantly degrading to poor. The headwaters of the Mangatainoka River rise in the Tararua Forest Park, where the water quality is pristine. But as the river goes downstream, it worsens because of intensive land use. Downstream of Pahiatua, the river has an extremely high concentration of nitrogen, impacted on by the Pahiatua sewage discharge along with other smaller discharges. Blue-green algal blooms negatively affect recreational use, especially around the Mangatainoka township. It is generally safe for swimming at low flows when the algae is absent.


Very poor. A coastal dune freshwater lake with significant biodiversity values. Historically, it was affected by Levin's sewage discharge, which was halted in the 1980s. There are ongoing issues with the phosphorus that remains in the lake from this contamination. Although faecal contaminants are low, the lake's extremely high nutrient concentrations mean recreational use is often inhibited because of frequent toxic algal blooms.


Generally good. The river is pristine at its headwaters, but several tributaries have poor water quality as a result of town sewage discharges from Taihape, Hunterville, Marton, Halcombe and Sanson. The river is generally safe for swimming at low flows. But below the Bulls bridge, the water quality degrades to of industrial discharge and intensive land use. The river is subject to green slime throughout much of its main channel at times, but it does not suffer from blue/green algae.


Good, significantly degrading downstream. In its upper reaches, the river has very high water quality and is safe for swimming. Nutrients are not significantly elevated and there is not a lot of slime on the bottom of the river. But at high flows the river is affected by sediment, nutrients and faecal contaminants. Downstream of Feilding, the Oroua is impacted by the Feilding Sewage Discharge, which causes high nutrient concentrations and growths of slime on the bed of the river. The water degrades continually until reaching the Manawatu River.


Generally good. The river is very clean in its headwaters in the Tongariro National Park. Nutrient levels are low throughout the river. It is heavily impacted by sediment and has water clarity issues because of soil erosion problems throughout the catchment. It is generally safe for swimming, but blue/green algal blooms do occur in areas around Taumarunui."

Where would you and your whanau like to swim?

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