The damage to the quality of water in Lake Auburn — and its cost if Auburn’s mayor and council make the changes they have planned — could require between an estimated $30 to $40 million for a filtration system.

Water rates would at least double in Auburn, Lewiston and Poland.

This is absolutely unnecessary.

While few lakes in the United States have been able to avoid this cost, several Maine lakes have done so. China Lake avoided it until recently, but then decided to develop around China Lake and the result was a new, costly filtration unit for their water users.

Sebago Lake is much larger and deeper, and still clean. We must keep Lake Auburn clean.

Lars Gundersen is a recent Bates grad who studied the lake with Holly Ewing as his Bates instructor and guide. His analysis is powerful. Holly Ewing is outstanding and a good potential information source for all Auburn decision makers, and has been very concerned about keeping Lake Auburn clean and drinkable.

Lars’ senior thesis was a study of Lake Auburn and, in 198 pages, contains a solid plan to allow Lake Auburn to continue to be pleasant and safe for all.

Keeping Lake Auburn clean involves making sure that the two major pollutants — phosphorus and nitrogen — are monitored aggressively and that their entry into the lake is strongly limited.

Seventy-eight percent of the land around Lake Auburn was forested before the deforestation of the former dump began, and a healthy forest surrounding a lake is the most effective way to keep a lake clean.

Phosphorus comes from lawns, driveways, road systems and road construction, septic systems, fertilizers and farmland, and farm animals. Neglecting these threats would make it impossible to maintain our systems and avoid the potential $40 million cost of filtration. This will become more difficult as the earth warms, and rain becomes more intense, washing more material into the lake.

To protect the lake, we must do more to have forests grow and do their job. Roads around a lake must be checked to be sure that all sites that phosphorus could find an entrance to slide into the lake are monitored and improved.

Most of the water coming in from Turner is manageable. Human bowel waste will go into septic tanks. Ideally — and ultimately, perhaps necessarily — that do not go into such lake-safety systems will not be allowed.

As we set the area up for more agriculture, animal waste raises the same issues as human waste. Perhaps animals could be restricted to areas that are behind a small hill, blocking that waste from going into the lake.

A major concern is development in the area of the old dump. The plan for its development currently calls for 984 apartments, 120 town homes, a pool, a restaurant, a small shopping area, as well as four pickleball courts.

This is an area that, despite its history as a dump, never brought much phosphorus into the lake. The fact is that it was hilly and many hills sheltered the lake. Now most trees have been cut down, the hills modified and it appears that the development will border the lake, or at least be very close.

It is critical that the developer makes all information on planned lake protection public. This report should then be carefully studied by a very knowledgeable and committed organization with a reputation for flawless integrity, and only then approved by the Auburn Planning Board and — probably — the next council, due to time constraints.

An issue for this development is the elimination of recycling by the city. With some 2,000 people living in the area, and many more visiting, pollution of Lake Auburn with plastic is not a happy thought.

The last question which arises concerns our road system, the likely dramatic increase in traffic on all roads in this new development area. These are suddenly becoming very crowded before the new development and population surge.

What sort of traffic will 2,000-plus new people bring?

How many people will be working at the new restaurant or stores?

Roads cost money. We need to update and improve many, but planning for new population needs to be understood and begun before road traffic changes dramatically.

Auburn is a physically large city, and people are moving to Maine. It makes no sense to plan development around a fragile lake, and we need to choose areas that do not impact our water supply.

Let’s grow, but keep the lake free from harm. That focus will keep Lake Auburn clean, and water prices in line.

Let each councilor look at his or her neighborhood and find areas that could grow nicely. Their constituents would probably like that, especially with clean, affordable water.

Jim Wellehan was born in Lewiston and has lived and worked in the Lewiston-Auburn community his entire life. Former president of Lamey-Wellehan, which was awarded the Lifetime Achievement Award by the Natural Resources Council for the company’s work to reduce its carbon footprint, he served on the the board of NRCM and the Finance Authority of Maine, among many other community boards.