On earlier visitor maps, ZEALANDIA's Lower Dam was referred to as The Lower Lake and the Upper Dam as the Upper Lake. Originally, however, The Lower Dam was named The Lower Reservoir, which was an earth dam completed in 1878. Due to the European settlers wanting farmland, large fires in 1850 and 1860 cleared that area of its broadleaf forest. Some of the valley was farmed uptil 1906, then any remaining catchment area was bought for waterworks.
In 1908, building of The Upper Reservoir as a concrete gravity arch dam was completed. Then all the valley became a protected water catchment for Wellington City Council (W.C.C.). This area was bounded by Wright`s Hill in Karori and Pohill`s Brooklyn Wind Turbine. Replanting, especially of podocarps, began. Native trees also regenerated, e.g., tawa, Northern rātā, rewarewa, kahikatea, totara, matai and rimu.
Due to several nearby earthquake faultlines and W.C.C. concerns about the dams cracking in a big earthquake, both reservoirs were decommissioned. Around 1991, The Upper Dam was decommissioned and The Lower Dam was decommissioned as in 1997. This allayed Civil Defence worries that the cracked dams` huge deluge of water would cut off Karori after a severe earthquake, i.e., ‘The Big One‘!
However, there reservoir catchments were identified as specially significant in the ‘Natural Wellington‘ Project. That was due to it being a self-contained, large habitat suitable for a Big variety of native animals and plants, e.g., mahoe and New Zealand Tree Fuchsia/Fuchsia excorticata.
W.C.C. and Wellington Regional Council carried out a feasibility study in 1993. Public consultation took place in 1994 and the idea of a sanctuary was approved. Mid-1995, The Karori Wildlife Sanctuary Trust was set up, so the proposed ‘mainland island‘ wildlife sanctuary could be implemented.
The two heritage dams are parts of many tracks, e.g. The Lake Road for The Lower Dam and Round The Lake for The Upper Dam. In The Lower Dam, there is a large colony of manu [birds]. You can easily see the nesting shags from The Pontoon or by using the binoculars on The Lake Road. You are more likely to spot Scaup [papango] and Brown Teal [pākete] in The Upper Dam.
There is a great deal of fascinating historical background and photos about these heritage dams in The Boatshed and the iconic Valve Tower. They are both in The Heritage Area near The Visitor Centre.
Recently, New Zealand celebrated National Volunteer Week. Due to a very knowledgeable Volunteer Walking Group Guide, Simon Nathan, I learned a lot about these two dams. For example, there are outlets for The Lower Dam on the extreme far right bottom corner of The Heritage Area.
Kia ora/Thank you Simon and all the many other ZEALANDIA volunteers – especially those who guide tours to these amazingly old heritage dams.