State of the LakeState of the Lake20082008

For the

Currents of Change – Narragansett Bay Estuary Program

The Lake Champlain The Lake Champlain BasinBasin

The Basin:The Basin: 21,326 square kilometers

The Lake: The Lake: 1,127 square kilometers

Over 122 meters deep

965+ kilometers of shoreline

193 kilometers long

LakeLake ChamplainChamplain

• Lake Segments:

The Lake is divided into five distinct areas, each with different physical and chemical characteristics and water quality.

•Drinking Water Use:

200,000 people or about 35% of the Basin population, depend on Lake Champlain for drinking water.

• Population in the Basin:

571,000 in 2000. About 68% live in Vermont, 27% in New York, and 5% in Quebec.

Density is about 61 people per sq. mi.

Missisquoi Bay

•Greatly exceed P target

•Seasonal BGA blooms

•Extensive agriculture

South Lake

•Exceeds P targets

•Excess weed growth

•Water chestnut and Eurasian watermilfoil

•Much of the watershed is intensively farmed

Inland Sea/Northeast Arm

•Exceeds P targets

•Seasonal BGA blooms

•Eurasian watermilfoil

•Extensive agriculture and urban areas

Where is P coming Where is P coming from?from?

• Point sources = 10%

• Nonpoint sources = 90%

Where is P coming Where is P coming from?from?

Land Use StudyLand Use Study• Land Use in 2001

– 66% Forest– 14% Agricultural– 5% Urban

• Land Use Change since 1992– urban land increased by 2%– Agricultural land decreased by 5%

• Phosphorus loading estimates 2001– Urban/suburban 46%– Agricultural 38%

• Previous estimates from 1991 study:– Urban/suburban 37%– Agricultural 56%

Updating the Lake Champlain Basin Land Use Data to Improve Prediction of Phosphorus Loading. LCBP Technical Report #54Troy et al. 2007

Is Blue Green Algae a Is Blue Green Algae a Problem?Problem?Yes, especially in Missisquoi Bay, St. Albans Bay, and smaller northeastern bays, but most of Lake has never had a dense bloom

Skin irritant at low exposure levels. If ingested in quantity: gastrointestinal problems and serious liver/nervous system damage.

Alert System relies on collaborative research funded by LCBP and the Province of Quebec.

A Health Risk?

What are our Management Responses?

Education/Outreach

Farm Best Management

PracticesUrban Best Management

Practices

Wastewater Treatment

Can I eat the Fish?Can I eat the Fish?

Yes, but:

• Fish consumption advisories are issued due to concentrations of PCBs and Mercury

• VTANR, NYSDEC and QC MDDEP monitor toxin concentrations in various fish

• Longer-lived, large predatory fish tend to have higher mercury concentrations

• PCB-related advisories are the result of high PCB concentrations in Cumberland Bay

Which Aquatic Invasive Species Threaten Which Aquatic Invasive Species Threaten the Lake?the Lake?