PHOTO
The Waipori township, west of Dunedin, was flooded in 1924, erasing a once-bustling gold-mining town.
Local amateur historian David Still said the lake was at its lowest since the 1970s - and in his living memory.
Items include glass bottles, crockery, bricks, horseshoes, pipes, machinery, farm equipment and a couple of unidentifiable objects.
Two sizeable items, which appear to be the remains of a gold-mining dredge and farming equipment, are now visible.
Mr Still had never seen either of the items until contacted by the Otago Daily Times and described it as "fantastic news".
"The lake [level] has always fluctuated up and down throughout the year because of electricity demand and if maintenance needs to be done.
"But I have not seen the lake this low since the 1970s."
The town was once home to more than 4000 people and was settled between 1861 and 1924. Those living there included Irish, English, Scots, German, Italian and Chinese miners.
Mr Still described it as an important part of the country's history and said it should be preserved.
Otago Southland Heritage New Zealand Area Manager Denise Anderson agreed.
While she was aware water levels were "significantly low", she was unaware items had been exposed, until contacted by the ODT.
She confirmed senior archaeologist Matt Schmidt would visit the site to update and record the finds.
He identified two of the bigger items as "wagon wheels and a plough".
Mrs Anderson said it was not possible to confirm the age of the items from photographs but guessed they could be pre-1900.
"The photographs of the items exposed on the shores of the lake above the Waipori No2 dam now the water level has been lowered are exciting and very interesting."
She warned would-be prospectors and reminded looters that it was "unlawful" to disturb an archaeological site as there could be "evidence relating to the history of New Zealand".
"Archaeological sites are irreplaceable parts of our heritage."
Mr Still, who has studied the site for 50-odd years and is part of a heritage group trying to protect the area, also planned to visit in the coming days.
"The lake will refill with water at some stage and it would be good if some of those larger relics could be removed.
"The preservation of its history is important and making that information available for the public.
"We already have a lot [of relics] in storage, including a photo collection of over 300 photos.
"It is very important because having these photographs from earlier days we can then go on to site, where these relics are, and photograph them 100 years later."
He gave an insight into the items.
The concrete structure visible was part of a water tower and was the killing shed/meat store.
He first visited the site 50-odd years ago and is something of an expert on local history.
"The fact that this [the lake] has gone down and exposed all these paths is unusual."
"The footpaths would take you around gardens and there may be the remains of a tennis court nearby."
The town shot up quickly when it was formed on December 17, 1861.
Records show some men heading overland from Dunedin to join the gold rush at Gabriels Gully, near Lawrence, found gold in Lammerlaw Creek.
In less than a week, about 400 gold miners were working the banks of the creek and its tributaries.
Mr Still hopes the history will be preserved and is part of a group setting up the Waipori Goldfields Charitable Trust.
He described it as timely - they plan to meet in the coming weeks to talk about fundraising.
The ultimate aim was to build a museum to house all the artefacts, including any new ones.
Trustpower did not respond to questions about how long the levels would remain low, or whether it was a permanent fixture.
Trustpower reduced the level by 2.1 metres following a safety review which found the dam walls could fail in an earthquake.
The lake feeds Waipori's four stations.