Two phrases you don’t often find in the same sentence: “state park” and “sewer plant.”

So eyebrows are bound to arch a bit over plans to construct a wastewater treatment facility in Fay Bainbridge State Park at the island’s north end, one of some two dozen recreation areas in Washington earmarked for such a plant. The state has set aside $1.3 million to put a cutting-edge “membrane” treatment system at Fay Bainbridge to ease septic problems there; depending on interest, the Point Monroe and Lafayette Avenue neighborhoods also could tie in.

Count this newspaper as among the early skeptics – many things might inspire a frolick in the Fay Bainbridge surf, but a churning sewage clarifier tank isn’t among them. And should the precious ground of a public park really be devoted to wastewater treatment? Seems a bit of a stretch from the picnic shelter and horseshoe pit. Yet by all accounts, the treatment system as proposed can fit into a vault the size of the park’s lower restroom and would be neither visible or obtrusive. The filtering technology is said to have evolved to the point that the treated effluent would be clean enough to water the lawn.

Assuming all this to be true, worth asking now might be whether the park sewer plan really goes far enough.

Bainbridge Island’s Comprehensive Plan offers little guidance about sewer planning, beyond existing service areas in Winslow and south Bainbridge, and – someday, perhaps – the extension of lines to Rolling Bay and Island Center. But if you accept the idea that shoreline septic fields are a great source of pollution in Puget Sound – clearly, the state does – then it’s waterfront neighborhoods that should be getting future sewer service. The higher densities there would also provide economies of scale to make treatment more affordable.

Recent lessons at the south end are instructive. There, the independent sewer district serving Fort Ward built a small treatment plant under court order to clean up the waste produced by just 78 homes. Thanks to city fortitude, four outlying neighborhoods including Emerald Heights – long plagued by failed septic systems – and the shoreline areas of Pleasant Beach, Point White and Rockaway Beach are now tied in, keeping septic pollutants out of Puget Sound. The plant now serves more than 450 island residences and has a capacity of perhaps twice that.

Is it time to revisit the city’s Comprehensive Plan, with an eye toward more shoreline sewer service? It would seem so. New goals could include more “pocket plants” like the one proposed for Fay Bainbridge State Park – it will be an excellent pilot project for the community to evaluate. Or perhaps the city should consider a larger, more conventional plants to bring still more shoreline neighborhoods into the fold. Neither option would be cheap or quick, with land costs, permitting issues and the inevitable public outcry over “promoting growth” that would come with any such proposal.

But if Bainbridge Island is serious about the environment – and we sure talk a good game – sewer service for shoreline neighborhoods makes great sense.

A newly minted “Fay Bainbridge State Park and Wastewater Treatment Plant” may well set the best example.