Press Release – Greater Wellington Regional Council
With the turn of a tap, water has begun to fill the Regional Council’s newly-strengthened and enlarged water storage lake at Te Marua.
The earthquake-strengthened lake is the second of the region’s two lakes to be upgraded and will take about two months to fill to its 1660 million-litre (ML) capacity, depending on river conditions.
When full, the combined storage of the two lakes will be 3730 ML, which is about four times the volume of Wellington’s Westpac Stadium.
The completion of upgrading work on the two storage lakes at Te Marua brings them up to current dam safety guidelines and delivers increased water storage capacity for the region. The lakes provide a backup water source for Upper Hutt, Lower Hutt, Porirua and Wellington.
“The capacity increase of the two lakes combined will give us an extra 430 million litres of stored water – this amount could be enough to maintain water supply for up to two weeks longer in conditions similar to last summer’s drought,” says acting water supply general manager, Noel Roberts.
Initially scheduled to take place last week, the filling had to be postponed due to heavy rain over the weekend.
“It’s important that the water that is used to fill the lake is reasonably clean, to minimise sediment content and the risk from contaminants. Putting only clean river water into the lakes means it’s easier and less costly to treat before it’s supplied to our customers,” says Noel.
Lake filling began with a modest 400 litres (about three baths’ full) per second, but will increase to as much as 1000 litres per second once the water levels are high enough to stop incoming water disturbing the lake’s bed.
The strengthening project has been completed on schedule and within budget, costing a total of $12.4 million.