National Party MPs for Tukituki and Wairarapa respectively, Craig Foss and Alastair Scott, said they were "rapt" with the water uptake.
"This is fantastic news for all of Hawke's Bay," Mr Foss said.
"The project continues to gain momentum as barriers and hurdles are beaten and confidence rises, creating so many new job opportunities for our families."
The Government has given a total of $6.88 million to the Ruataniwha project through the Ministry for Primary Industries' Irrigation Acceleration Fund.
Industry lobby group Irrigation New Zealand chief executive officer Andrew Curtis said it was good news for Central Hawke's Bay as it would re-invigorate the shrinking communities of Waipukurau and Waipawa.
Forest & Bird's campaigns and advocacy manager Kevin Hackwell said there was still a legal hurdle on the horizon, with an appeal sitting in front of the courts concerning the legality of the proposed land swap under the Conservation Act.
He said it was an important issue for Forest and Bird as it puts in question the protection of nearly a third of the public conservation estate.