Taking advantage of downtown waterline replacement to encourage businesses to install fire sprinklers is a good idea that should have been considered before now.

Discussions are under way between downtown property owners and the city’s utilities department on a proposal to reduce the cost of tapping into the new waterlines being laid in the 700 and 800 blocks of Massachusetts Street. It normally costs $6,000 for a business to tap into a water main to supply a fire sprinkler system, but the city is considering cutting that fee in half; $3,000 would cover the cost of materials but the labor would be free. A plan also is being considered to allow businesses to pay the fee in installments.

It makes perfect sense to do this work now when the lines are being excavated and replaced. It’s hard to understand why similar plans weren’t pursued last year when water lines were replaced in the 600 block of Massachusetts.

It’s also easy to justify the city offering a financial incentive to increase the number of downtown buildings protected by fire sprinklers. The public has a special interest in reducing the possibility that a large portion of the city’s downtown could be decimated by a fire that starts in one building and spreads quickly to others. Such a fire devastated the historic downtown in Fort Scott last year.

Local firefighters long have been concerned about a significant downtown fire that would be dangerous to fight and difficult to control. A catastrophic downtown fire was narrowly avoided in 1997 when a blaze gutted the Sunflower Outdoor and Bike Shop, 802 Mass., and threatened to engulf neighboring structures.

All it would take is an unattended candle on a second-floor downtown apartment to set off a destructive chain of events, firefighters have warned.

Some businesses already have installed sprinkler systems and the city should take reasonable action to encourage as many others as possible to do the same. Cutting the cost of tapping into the new waterlines during construction is a good way to encourage property owners along Massachusetts to protect not only their own investment but downtown’s history and the atmosphere that is so important to Lawrence residents.