Long recognized as a regionally important resource, Great Madow is a large open basin at the headwaters of the Melvin River that helps protect Melvin Bay and the upper part of Winnipesaukee Lake by intercepting floodwaters and capturing sediments and nutrients from upstream sources before reaching the lake. Located on a near-level bench between NH-171 and Sodom Road, Great Meadow was the subject of intensive water quality and biological sampling by the Tuftonboro Conservation Commission in 2001–2002. It proved to be comprised of excellent water quality and wildlife habitat and was found to be regionally significant in its contribution to open space and biodiversity. A permanent conservation easement assigned to a third party will help ensure these long-term benefits to the citizens of Tuftonboro.

• Largest wetland complex in Tuftonboro.
• High water quality as tested in 2001-2002.
• The site is above the largest drinking water supply in the region.
• Has regionally significant wildlife habitat for migratory waterfowl.
• Contains excellent hunting opportunities for deer, moose, and game birds.
• Provides excellent recharge for the area aquifers.
• Includes old-growth swamp forests in exemplary condition.
• 22 different natural communities, some rare in the state.
• The highest ranked wetland for ecological integrity in the region.