Dorchester District 2 is facing a $1 million shortfall in 2013-14, unless County Council agrees to a tax hike to make up the difference.

The proposal would cost an additional $10 per year on a $25,000 vehicle or $40 annually on a business but does not affect the taxes on owner-occupied residences. It would be the first increase since 2009.

District Chief Financial Officer Allyson Duke presented the budget Monday to council. The final reading is scheduled for June 3.

The district’s proposed $157.8 million budget includes $1.38 million for 23 additional teachers to handle an expected 500-student increase, $2.25 million for salary increases (mostly state-mandated), and up to $100,000 more for the district’s contract with Durham School Services. All other expenses stay the same.

Asked afterward if he supports the district’s request, Councilman Jay Byars, a former District 2 teacher, said, “I’m not saying yes or no, but I will make some phone calls so that I understand what they are asking for. We’ve got to make sure our schools are adequately funded, and they can show the numbers. They aren’t being unreasonable. ”

The operating budget is separate from the $179 million building program approved by voters in November, which is expected to increase taxes on a $150,000 home by $102 annually, possibly starting with the 2014 tax bill.