The occasion was the 75th anniversary of the official Waitaki dam opening, and owner Meridian Energy Ltd was overwhelmed when it opened it to the public yesterday.
More than 500 people toured the dam, including its impressive control room with switches and dials set in Italian black marble.
For safety requirements, people registered at Kurow and were taken by free buses to the dam for their tours then returned to Kurow.
The first bus at 9.10am was nearly full, with 33 people on board.
It never let up from then, with most of the 11 bus trips full and some missing out at the end of the day.
All who got to the dam had a tour lasting up to an hour, from the powerhouse, with its seven generators, to the large control room, which became redundant in 1998 when control was computerised and centralised at Twizel.
The tours were only part of a day's celebrations.
At 3.30pm 135 invited guests gathered in the powerhouse for a welcome by Meridian general manager of markets and production Neal Barclay.
He outlined the history of the Waitaki dam and the part it played in New Zealand's development, not just meeting a growing demand for electricity but also in its social structure.
It was historically important as the first of eight powerhouses to be built on the Waitaki River, and played an important role in New Zealand development.
Two Kurow men associated with the project - the Rev Arnold Nordmeyer and Dr David McMillan - went on to become members of Parliament in the Michael Savage government and schemes they developed to help dam workers formed the basis for New Zealand's social welfare system, he said.
A plaque to the memory of Dr McMillan was unveiled in the powerhouse by his grandson Malcolm McMillan.
Thomas Ewart (6), whose great-great-grandfather was blinded working on the dam, cut the anniversary cake.
The Pearson family has had a long association with Kurow, the buses used yesterday carrying the Pearson name.
Last night, a buffet meal and dance were held in the Kurow Hall for about 200 people.
