For years, city officials – including mayors Paul Helmke, Graham Richard and Tom Henry – have warned city residents that a mandatory and expensive project to reduce pollution into the three rivers was on the horizon.

While lots of numbers with lots of zeros behind them have been discussed over the years, a picture of just how much each household and business will pay emerged this week. Like the 1 billion gallons of raw sewage the city dumps into the rivers each year, the picture of impending sewer rate increases isn’t pretty.

Under the plan that Henry and his City Utilities staff unveiled Tuesday, sewer customers will pay 23 percent more beginning July 1, with a typical bill rising from $18.99 to $23.27 per month. Similar rate increases would take place over the following four years, resulting in sewer bills nearly doubling by 2013.

That may not be the end of the increases, because the project will continue through 2025. City officials are hoping that with more than 100 Indiana cities facing similar mandates to reduce water pollution, state government will offer money to Fort Wayne and other local governments. But given state officials’ reluctance to raise taxes, no one should count on state aid.

City officials have obtained $1.5 million in federal money and will continue to seek more. But again, there is no guarantee at the federal level, either.

Don’t blame Henry for the pending increases. For decades, Fort Wayne – and other cities in Indiana and nationwide – dumped untreated, raw sewage into rivers. During periods of heavy rain and quick snow melt, sewage treatment plants are unable to handle the volume of waste, so combined sanitary and storm sewers bypass directly into streams.

In the 1970s, the federal government began setting standards to reduce the amount of sewage being dumped into rivers, and negotiations between federal and city officials have been going on in earnest for at least seven years.

Ideally, the city would completely eliminate the combined sewer overflows, or CSOs, as government officials call them. In Fort Wayne’s case, complete elimination would be astronomically expensive, so much of the negotiations have centered on how much less than 100 percent is acceptable.

The two sides agreed to a $240 million plan to eliminate more than 90 percent of the untreated sewage going into rivers. The city will use three main approaches:

•Separating storm and sanitary sewers so stormwater goes straight to the river while sewage goes to the plant for treatment.

•Creating storage areas to hold waste from combined sewers until stormwater subsides, then gradually releasing it for treatment at the sewage plant.

•Expanding the sewage treatment plant’s capacity.

The city faces an unfunded federal mandate to improve its sewage system, but the city should be doing it anyway. Polluting the rivers does more than damage the environment – it creates health hazards, it hurts quality of life, and it hurts potential for economic development.

The city will enjoy several side benefits, including improved sewers that will last longer and work better, elimination of septic tanks in some areas and improvements to the sewage plant.

In coming weeks, City Council members will debate the proposed increases. As much as the rate hikes will hurt residents already hard-pressed to pay bills during this bleak economic period, failure to raise them will result in fines and additional costs, ultimately making the project even more expensive. And even with the increase, the city’s sewer rates will still be below those of most area cities.

The Henry administration has responsibly taken steps to spread the increase over several years rather than surprise residents with one huge jump in rates. The council has little choice but to approve the rate increases.