Now 55 years later and the dam, about 60 kilometres north of Inverell, is marking a major milestone.

WaterNSW has discovered a trove of historical photographs from 1969, when the dam was completed.

Officials also tracked down former workers from the site and recalled their memories.

Pindari was the first dam built in the north of NSW. It has a capacity of 312 gigalitres of water, sourced from the Border Rivers system and used for irrigation and town water for Ashford, Yetman, Boggabilla, Boomi and Mungindi.

Building the dam took two years and was a major feat of its day. For the first time construction of the infrastructure was outsourced, to French civil engineering firm Citra.

Dudley Tickle, 86 and who now lives in Tamworth, was one of about six contractor inspectors on the site.

He moved his wife Yvonne and toddler son Gary to Pindari in 1967, spending the next two years working there.

"We lived on site in weatherboard homes, transported from Wyangala dam," Mr Tickle said.

"We worked six days a week, sometimes 12 hours a day.

"As inspectors we supervised the actual work by the Citra workforce, to ensure it was done to the specifications set down in the contract.

"One of our tasks was to check the concrete leaving the batch plant. We took test results, and had to keep control of the water-cement ratio."

Sunday, the workers' one day of leisure, was usually spent in Inverell, either at the bowling club or in the summers, at the swimming pool.

Occasionally some workers would fossick for sapphires in the region, while others would hit a round of golf at Ashford.

Mr Tickle's most vivid memory from his days at Pindari was the violent, vertical lightning strikes.

"I have never seen storms like it before or since," Ms Tickle said.

"It was chain lightning that travelled vertically from the sky. I don't know why the area attracted such lightning strikes, maybe the granite rocks, but that lightning was something I will never forget."

Inspectors, engineers, tradies and ancillary workers all helped build Pindari, one of the state's 20 major dams.

The work could be gruelling, especially in summer, when the mercury was known to hit 40 degrees.

But there was camaraderie among the workers, which included Ashford born and bred Ken Walsh.

He was a 15-year-old lad at the time.

"It was my first job and I was involved in the ground works," Mr Walsh, who now lives in Tamworth and is aged 73, said.

"My job was to help install the sewer mains and stormwater drains in the village there, I worked with about six or 10 men often working 10 and 12 hours shifts. It was tough work."

About 560 officials guests and residents attended Pindari dam's official opening on March 21, 1969.

According to a report in The Inverell Times, it was a warm day with thunderclouds gathering.

Mr Askin released the first regulated water into the Severn River, after which Ashford Shire president Cr J.R Black extolled "the virtues of the first dam in the north".

Mr Tickle and his family stayed behind at Pindari after the official opening to tidy up and complete last-minute jobs at the site.

He has a lasting memory of his last day at Pindari; May 28, 1969.

"It was the day my daughter was born," Mr Tickle said.