Nov. 8--St. Joseph residents may need to brace for another double-digit increase in their water rates -- one that the water company says it needs desperately to upgrade its aging infrastructure.

The 28 percent increase would add $100 to the annual water cost of the average single-family homeowner in St. Joseph and give Missouri American Water's local operations millions more in revenue each year.

The utility cites roughly $2.6 million in improvement projects in the past year and scheduled for the next six months that it must recoup with its latest water hike:

-$296,000 to establish a lagoon discharge system to safely release water into area public streams.

-$375,000 to install a new 20-inch main under railroad tracks on Illinois Avenue in the South Side.

-$96,000 to cover remaining costs to install more than three miles of 12-inch main in southeast St. Joseph.

-$609,000 to replace old water meters.

-$343,000 to replace old water service lines from street mains to customers' homes.

-$166,000 to replace old fire hydrants.

-$720,000 to pay for smaller projects such as dehumidifiers and a distribution pump at the utility's treatment and distribution facility.

For the average single-family homeowner, a 28 percent increase would mean a new annual bill of roughly $455, compared with the current bill of about $355. The increase, if passed by state regulators, could take effect within a year.

Missouri American filed its rate request a week ago. The utility says costs for energy, insurance and water main repairs have outpaced the rate of inflation.

"If we did not make these improvements, the reliability factor would go down tremendously," said Mike Wood, operations manager in St. Joseph. "And the only way to recover those costs is through rate increases."

By making upgrades, Missouri American says it's being proactive and also complying with state mandates. By early spring, it plans to replace a pipline more than a century old on Illinois Avenue that, if it were to rupture, would wash out and stop all trains headed south, the utility says.

For public safety, Missouri American also replaces older fire hydrants and color-codes them so firefighters can easily tell the pressure range. The utility says there are nearly 3,100 hydrants in the St. Joseph area.

State regulations also require that utilities replace water meters every 10 years. Missouri American says it changes between 2,000 and 3,000 local meters each year.

The utility serves about 32,500 residential and business customers in the St.