Tahoe Keys: The Marsh That Isn't There Anymore

Before nineteen fifty-nine, at the south end of this lake, there was a marsh. It was the largest freshwater marsh in California. The Upper Truckee River ran into it before entering the lake. For thousands of years, that marsh filtered the water. Sediments settled out. Nutrients were absorbed. The lake received relatively clean water at its largest tributary inlet. That is what a marsh does.

Between nineteen fifty-nine and nineteen sixty-three, the marsh was dredged and filled. A developer built a residential canal subdivision called Tahoe Keys on roughly seven hundred forty acres, destroying about half of the Upper Truckee Marsh. More than fifteen hundred homes, private docks, a marina. The regulatory standards of the nineteen fifties permitted this. Those standards were later recognized, not by the developers but by the scientists and resource agencies who spent the following decades studying what happened, as having been wholly inadequate to protect the lake.

The filtration function of the marsh was permanently destroyed. There is no restoring a filled marsh to its original hydrology.

What the dredging also did was introduce invasive aquatic plants into the canals. Curlyleaf pondweed and Eurasian watermilfoil colonized the new channels and found their way into the lake. These plants decompose in summer and release nutrients into the water that drive algae growth. The algae clouds the water. The cloudiness is part of what shows up in the Secchi disk readings that researchers at UC Davis have been taking every year since nineteen sixty-eight.

California and Nevada resource agencies have spent decades and hundreds of millions of dollars trying to address the damage the Tahoe Keys development caused. The Tahoe Regional Planning Agency was founded in nineteen sixty-nine, largely in response to what happened here and at other development sites around the basin.

The houses are still there. They are worth a great deal of money. The marsh is gone.