Mount Pleasant Academy Principal Jane Davis has worked in the Charleston County School District since its inception 46 years ago, but she never had addressed the school board until this week.

Davis told the board Monday night that she wasn't speaking for herself, but for the district's other principals and assistant principals. She asked the board to support the recommendations of a new salary study, because she said principals are essential to schools' success.

"Good teachers will not work for bad principals," she said. "Without an excellent principal, you won't have an excellent school. To attract and retain the best, our salaries must be competitive, and they are not."

The school board seemed to agree with Davis when it signed off on roughly $8.5 million in pay increases for most district employees, starting in the 2014-15 school year. Principals and assistant principals will see the biggest jump in their salaries.

"It's really sending a message to our employees that they are valued," said Bill Briggman, the school district's executive director of human resources.

The pay hikes are a result of a salary study by a Minnesota-based compensation consulting firm, Fox Lawson & Associates. It reviewed the classification and compensation of the district's roughly 5,500 employees.

No employees' pay will be decreased, and the raises will bring workers' pay closer to the fair market value of their positions. The fair market value was based on a custom survey of comparable school districts, as well as the local public and private market.

Most teachers will receive a raise, but it won't be significant because the study found that their salaries already were highly competitive comparatively in the state.

The board will have to approve again the $8.5 million expenditure in the context of its full budget later this spring, but Chairwoman Cindy Bohn Coats doesn't expect that to be an issue. She said she couldn't imagine a more important program, concept or idea that would come forward that would trump the increases for district employees.

"I don't see that happening," Coats said. "If there's anything to be concerned about, it would be that because we are spending this money, there are an awful lot of things we cannot spend money on."

She doesn't think the board has backed itself into a tax increase. The board also will be asked to consider an additional $3.8 million to provide every employee a step raise, or money for an additional year of experience.

The amount of the pay increases will vary by employee, but the board agreed to pay half of the difference between employees' actual salaries and what was determined to be the fair market value of their positions. That means if an employee is making $40,000 and the study found that position should be paid $50,000, the employee will see a $5,000 raise.

That increase was particularly important for the district's principals and assistant principals, who didn't make what they were worth based on their experience, Briggman said.

Charleston has seen a 60 percent turnover in its principals' positions during the past three years, and one of every five principals who left went to another district, he said.

"I talk to principals when they're leaving, and they usually tell me it's for a higher salary or the potential to make more," he said.

That school-based administrator turnover also affects teacher recruitment, Briggman said.

"Any time that a building-level administrator decides to leave for another position, sometimes you see teachers leave because they're following the administrator or they're concerned about who will be the next leader," he said.

The current average salary for Charleston principals is $85,898, but that will go up to $93,055 starting July 1. The average Berkeley principal salary is roughly $95,000. Figures for Dorchester 2 principals were not available Wednesday.

Davis said the district's current salary system has meant that a principal with 14 years of experience makes $600 more annually than she does with 46 years of experience.

"There's no incentive to stay with Charleston County," she said. "As we all know, good principals are in demand. They're courted."

She said this new system will be a huge help in retaining quality leaders, as well as attracting more high-quality applicants.

"Principals and assistant principals stand to benefit the most, but I think this is going to be helpful to office staff, teaching assistants and other people at the school level," she said.

Reach Diette Courrégé Casey at @Diette on Twitter or (843) 937-5546.