Wairarapa Water Use Project director Michael Bassett-Foss said the geotechnical information would help better define construction costs which would affect the cost of water and the viability of any scheme.
"Until this year site investigations have involved desktop research and visual inspections only. This was the first time we have conducted any physical work - digging test pits, taking soil samples and looking more closely at surface material and land features. The work was at a preliminary level, based on observations and engineering judgement, rather than full analysis," he said.
"There were no major surprises but we did learn more about several geological issues at the White Rock Road and Black Creek sites which we would like to look at further as soon as possible.
"The aim of this would be to establish whether these issues were sufficiently significant to discount either site."
An assessment of water distribution arrangements for each site is to be completed by October. "We expect to be in a position by December this year to start discounting the least viable storage sites, helping to give affected landowners certainty."
- For information and reports on Wairarapa Water Use Project: www.wairarapawater.org.nz