Upper Saco River

Both its biological resources and economic uses make the Saco watershed a conservation priority.

The Saco River Floodplain is the largest intact floodplain in New England. Spring rains bring the river water over its banks, where it scours the landscape, making room for rare plants and animals.

The water then percolates slowly through the fine glacial soils of the floodplain and returns to streams and springs naturally filtered and purified — giving the Saco some of the cleanest water in Maine.

The Saco watershed is not wilderness: the river valley has been inhabited for thousands of years. In its bottomlands, farmers benefit from fertile floodplain soils. Its uplands include woodlots that have been managed for generations and pastures that have only recently reverted to forest.

The groundwater of the floodplain provides drinking water to over 100,000 people. Tens of thousands of visitors flock to the river each year for canoeing, camping, swimming, hunting, and fishing.

The combination of biological resources and economic and recreational uses in the Saco watershed make it a high priority for conservation. At stake are not only the rare plants and animals that call the river home but also the livelihoods, water supplies, and recreational opportunities of thousands of people.


High property values in Southern and Western Maine area are spurring unsustainable residential and commercial development. Every slab of concrete or foot of asphalt laid on the floodplain hampers the natural water-purification process and brings unfiltered runoff to the river.

The heavy flow of visitors flocking to the river to paddle, raft, and swim also takes a toll. Most visitors respect the river, but some trample fragile riverbank habitat or leave behind garbage that pollutes the river and its banks. Invasive species are also a potential threat to native plants and animals along the Saco.


The Upper Saco River Watershed supports populations of rare dragonflies and turtles. The floodplain includes some of the world's only remaining river-wash barren ecosystems — open sandy or rocky habitats that are home to rare plants such as false-heather. The upland forests of the watershed contain wide-ranging mammals such as fisher and bobcat.

What the Conservancy is Doing

Our approach in the Upper Saco River Watershed emphasizes connections: between the river and the land, between people and nature, and between the different communities along the Saco. To keep making these connections, the Conservancy is seeking public and private funding, as well as land donations.


The Nature Conservancy is collaborating with towns, counties, and organizations throughout the Upper Saco Watershed from New Hampshire to Hiram, Maine. We are also working with with regional organizations such as the Appalachian Mountain Club, Saco River Corridor Commission, Saco River Recreational Council, and Upper Saco Valley Land Trust. Our approach integrates education, research, and land preservation.

Education and Research

The Conservancy’s Saco River staff maintains a prominent presence on the river, educating visitors about the importance of clean water, protecting river habitats, and the "leave no trace" philosophy. We have identified fourteen key habitat types along the river that require special protection. We are also evaluating the impact of invasive plants and animals in the floodplain.

Land Conservation

We are working with private and public landowners to protect working forests and working farmlands along the river. In collaboration with local land trusts and with businesses like Hancock Land Company, we are protecting lands that are important to the integrity of the landscape and to maintaining water quality. This involves buying or securing donations of land or easements, and helping local governments and organizations make good decisions about land use. Our agreement with Hancock will allow us to leverage our resources in the face of high property values and will allow the company to foster sustainable forestry practices in the region.