Water rates in Philadelphia will rise by nearly 10 percent over the next two years, the Water, Sewer and Stormwater Rate Board announced Wednesday.

The increase will be phased in starting in July, when the average residential bill will go up by $3.44 per month. Another increase, averaging $3.18 a month, is to begin July 1, 2017. In total, the average monthly residential bill is slated to go from $67.43 to $74.05 over the two years, a 9.8 percent increase.

The Water Department had sought a rate increase of about 12 percent over the two years.

Officials have said the increase is necessary to repair and replace infrastructure and comply with regulations.

Public hearings on the proposed rate increase were held this year.

The last rate increase was in 2013. The current increase was the first set by the Water, Sewer and Stormwater Rate Board, a commission that reviews and approves the Water Department's requests. Previously, the department's commissioner approved rate-increase requests.

The board said it was also taking steps to implement a new "Income-based Water Rate Assistance Program," which would let some low-income customers pay reduced rates. That program is to begin taking applications in the spring, officials said, though details were still being worked out.

ebabay@philly.com @emilybabay 215-854-2153