Ecological effects of sewage and silt in Christchurch's streams and rivers

Environment Canterbury has carried out a number of surveys and studies into the effects on streams and waterways of wastewater inflows and silt deposits, and have released reports on their findings.

ECan's media release on the effects of untreated sewage being discharged into the lower parts of the Avon and Heathcote rivers and the estuary is here. According to ECan's map (here), the lower Avon is the part of the river downstream from the Fitzgerald Avenue bridge.

Also available are the following reports:

• Ecological effects of the Christchurch February earthquake on our city rivers
• Ecological effects of the Christchurch February earthquake on our city estuary
• Effects of wastewater overflows on oxygen and ammonia in the Avon and Heathcote rivers
• Christchurch February Earthquake: Effect on aquatic invertebrates
• Christchurch February Earthquake: Effect on freshwater fish of the upper Avon River
• Christchurch February Earthquake: Effect on invertebrates of the lower rivers
• Effects of seismic activity on inaka spawning grounds on city rivers
• Mapping earthquake induced topographical change and liquefaction in the Avon-Heathcote Estuary
• Effects of the Canterbury earthquakes on Avon-Heathcote Estuary/Ihutai ecology

The reports and map are here.
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