That overflow ward opened during winter last year in a future-proofing exercise and closed at Christmas.
"But as the number of people coming to the hospital continues to rise we've now made a commitment to open that up and keep it open permanently."
Howard said the hospital was in the same situation as highlighted by Auckland health bosses last week when they told the health select committee population growth and underfunding had put the health system at breaking point.
Last month Waikato Hospital's emergency department had the second highest number of presentations in one day, with 296 presentations on February 12.
Patients presenting at the ED regularly range between 240 to 270 and sometimes up to 290.
"Over the Christmas period we've been unbelievably busy. The hospital's been running at near winter numbers.
"People are taking bets on when we're going to go over 300 people in one day [in ED]."
Howard said the opening of the two new wards was a "mid-term" solution to the problem and there were other wards the DHB could re-use.
"We've probably got another two full wards that we could bring back online if we had to.
"If we progressively use the areas that we've stood down, if we refurbish them and get them up and running we're probably okay."
He said the long-term plan was to demolish some of the old ward blocks and replace them with three state-of-the art ward buildings, but that was a five to 15 year process.
The last time Waikato Hospital had a large increase in bed numbers was when the Elizabeth Rothwell Building opened in 1980 with 240 beds, then mostly for women and children.
Though the hospital recently underwent a multi-million dollar campus upgrade, Howard said it didn't deliver a significant increase in bed capacity.
Board members agreed to fund the new Menzies Building ward, which would be used as an Acute Surgical Assessment Unit from July.