Basics
Public Health
Human interactions with nearshore waters are primarily associated with
recreational activities and with consumption of treated and untreated waters drawn from the lake. The characteristics and quality of water used for consumption are regulated under separate state and U.S. EPA provisions. Existing state and local programs for tracking presence of harmful micro-organisms and toxic compounds serve as nearshore human health indicators.

Ultra-oligotrophic lakes do not generally have issues with toxicity or harmful microorganisms, unless there are discharges of sewage or waste. Sewage and industrial discharges are not allowed into Lake Tahoe, although surface stormwater runoff to the lake from urban areas and some recreational activities could conceivably contribute toxic chemicals or pathogens.
NRAP Focus Area Key Photo
State of Knowledge

The primary public health concerns associated with Lake Tahoe's nearshore are (1) harmful algal blooms; and (2) bacteria concentrations.

The first known harmful algal bloom occured in the Lake Tahoe Keys in August 2017. The level of measured cyantoxins was below any health concern, but the area was posted to protect pets.

The most recent comprehensive bacteria survey was conducted in 2009 as part of previous shorezone ordinance 

No Monitoring Programs are yet associated with this Focus Area.