HALIFAX -- Nova Scotia's Liberal government is counting on cash from marijuana sales to help it deliver a third consecutive balanced budget, which includes modest spending increases for a heavily stressed health system.

Overall, the province is projecting a $29.4-million surplus on a $10.8-billion budget, as it continues to make progress on debt control.

A fair slice of the estimated surplus -- roughly $20.8 million in fresh taxes and duties from projected sales of about 12 million grams of recreational cannabis -- depends on Ottawa getting the legalized marijuana system underway across the country.

Finance Minister Karen Casey said there are "still a lot of unknowns" on cannabis sales, and cautioned "we are not looking to make money" from them.

But she said years of fiscal restraint are starting to pay dividends, as the second-term Liberals are starting to sprinkle some spending into a health system plagued by doctor shortages and lineups of ambulances outside crowded ERs.

"It gives us the ability to make further investments in healthcare and education, while we continue to live within our means," she said in her speech.

Provincially owned cannabis stores are expected to begin sales in Nova Scotia once recreational marijuana sales are legalized, now expected in August or early September.

Premier Stephen McNeil said the weed revenue had to be budgeted or there would have been questions as to why not.

"We have to budget for what is the best assumptions that we have. All of those numbers we believe are doable if and when it comes forward."

McNeil said there are also implementation costs that are built into the budget across a number of departments, including justice.

Chris Enns, the 33-year-old owner of Farm Assists Medical Cannabis Resource Centre in Halifax, said in an interview that the government's estimates translate into roughly an ounce of marijuana annually per Nova Scotian over 19 years of age.

It's an overly optimistic plan, he said.

"Realistically what is going to happen is most Nova Scotians are going to go into the liquor corporation stores once or twice," said Enns. "Then they're going to appreciate the distributors they've been working with for decades will offer a marijuana product that's lower in price and superior in quality."

The biggest ticket items on Casey's spending list are in healthcare, which is seeing an additional $103 million over the previous budget -- though that's a small hike in the context of a $4.4 billion health tab that currently eats up close to four of 10 dollars spent.

That includes $19.6 million as part of a multi-year plan to recruit and retain more doctors, already announced by McNeil on Monday.

The opposition parties have repeatedly said that's overdue, given the province's pay rates for its doctors have fallen behind other provinces and tens of thousands of Nova Scotians can't find primary care.

There will also be money for 350 more people to get hip and knee surgeries in the year ahead, at a cost of $8 million. It comes as national statistics have consistently shown the province having some of the longest wait times in the country.

Meanwhile, there is $2.9 million more to be spent on mental health services, targeted at areas of the province "without quick access to out-patient clinics."

Advocacy groups have called for a major infusion of resources to the mental health system, saying the suicides of people with mental illnesses are directly linked to lack of quick access in crisis situations.

Karla MacFarlane, the interim Progressive Conservative leader, said she is disappointed there wasn't significantly more for mental health.

"We know that this province is in desperate need of psychiatrists," she said. "There is no real money there, there is no real plan there to increase mental health services and we have people struggling right across this province."

NDP Leader Gary Burrill brushed aside questions about the government's surplus, saying his concern is the "surplus" of people clogging up acute care beds when there is no significant funding for long term care. He said the saddest part of the budget is that there isn't funding for a single long-term care bed anywhere in the province.

Burrill said the sprinkling of funding for a variety of areas amounted to "salt and pepper with no meat, no vegetables and no potatoes."

Education funding received an overall increase of about $80 million over the previous budget.

That includes $15 million for inclusive education programs for children with special needs, and adds another $10 million to implement recommendations from the Council to Improve Classroom Conditions.

Casey is also promising to release a plan for new school projects by June 1, based on a list created by school boards that are about to dissolved under new legislation.

The education measures have been promised by the Liberals as part of the benefits of restraints on wage and benefits for 9,600 unionized teachers.

As a human rights case launched by two people with intellectual disabilities continues, the Liberals have produced a pledge for $16.2 million to help people move out of institutions, and $2.1 million to create eight small options homes, which could provide housing in the community for those people with some of the most complex needs.

Joey Delaney and Beth MacLean have recently argued before a human rights inquiry that the province has violated their rights by not providing them supported care in the community.

The province also unveiled its capital budget, large portions of which have already been announced, including $60 million for a total of $285 million for spending on highways, bridges and roads. The gravel road improvement program has been increased by $10 million to $20 million.

The budget projects a $15.1-billion debt, about $15,851 per resident of the province. However, that represents a steady decline in the debt relative to gross domestic product.