Water pollution is the contamination of areas of water, such as rivers, lakes and groundwater. It affects plants and organisms that live in these areas and can be damaging to the health, and survival of them. Water pollution occurs when pollutants are directly or indirectly discharged into the water without being treated. The area of Rotorua – New Zealand contains 17 lakes, some of which experience, or have experienced varying levels of water pollution.
Lake Rotorua has had serious pollution problems, more than any other lake in New Zealand. In 1969 Rotorua had a population of over 50,000 people. They contaminated the lake with sewage for many years and it was described as an “un-flushed toilet.” Today most of the pollution is from fertilisers that runoff from farmland.
As the diagram shows Lake Rotorua and Lake Rotoiti are linked – by the Ohau Channel. So what happens in Lake Rotorua affects the water quality of Lake Rotoiti. However they face different issues that require different solutions. Lake Rotorua’s city has more than 55,000 people living on the shores, with smaller communities scattered around its edge. On average there is an extra 15,000 visitors a day as its tourism industry attracts people from all over the world.
Over the years Lake Rotorua’s water quality has decreased despite a lot of environmental work. Water quality improved after a high-tech sewerage system was installed for Rotorua city in the late 1980’s. It has since deteriorated again from an increase of nitrogen in the groundwater. With so many people living in the catchment nutrients from sewage are an ongoing issue. This is being undertaken by a range of actions from the Council. An $18.5 million reticulation scheme for eastern lakeside communities is in progress, and there has been a major upgrade of the Rotorua City sewage plant which has now been completed....