Van Norden Dam Public Meeting 7-29-13

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Transcript of Van Norden Dam Public Meeting 7-29-13

Lake Van Norden Dam Truckee Donner Land Trust Public Meeting

David Shaw, Brian Hastings,

Ted Beedy, Barry Anderson

July 29, 2013

photo

Acknowledgements

• Chuck Kull, Holdrege and Kull

• Randy Westmoreland, USFS

• Gateway Mountain Center

• Norm Sayler

• Susan Lindstrom, PhD

• UC Davis Center for Watershed Science

• Aspet Ordoubigian, DSOD

• George Lamson

Overview

• Planning and regulatory framework• Approach• Sierra meadows overview• Historical context• Summary of preliminary findings

– Channel and meadow conditions– Plants– Wildlife– Bathymetry

• Description of alternatives• Next steps

Regulatory Framework

1. < 50 acre feet

-OR-

2. < 6 feet high

Regulatory Framework

Plants

USFS Manual 7500: Dam Planning, Investigation and Design

• Alternative 1: Full Breach

• Alternative 2: “Non-jurisdictional” dam with determination of hazard

Regulatory Framework

Plants

USFS Manual 7500: Dam Planning, Investigation and Design

• Alternative 3 (?): Existing dam with acceptable level of risk with dam failure

Investigation Approach

Goal:

Document existing conditions so that impacts associated with various alternatives can be evaluated and monitored

Investigation Approach

Study Elements:

• Historical and Cultural Resources Assessment• Channel and Meadow Assessment• Biological Resources Assessment• Bathymetric Survey

Next steps:

• Complete Channel and Meadow Assessment• Hydrology and Hydraulics Hazards• Monitor surface-groundwater interactions• Evaluation of Alternatives

Sierra Meadows Overview

HydroGeomorphic Meadow Types

(after Weixelman and others 2011)

• Peatland

• Depressional

• Lacustrine

• Dry

• Discharge Slope

• Riparian

• Subsurface

HydroGeomorphic Wetland Types

(after USACE 1993, NRCS, 2008)

• Depressional

• Slope

• Mineral Soil Flats

• Organic Soil Flats

• Riverine

• Lacustrine Fringe

Historical and Culture Events Lake Van Norden and Meadow

Date Event

9,000 yrs ago to historic contact Prehistory and Washoe/Maidu history

1844-1852 Emigrant Trail

1864 Dutch Flat Donner Lake Wagon Road

1868-69 Transcontinental Railroad

1870s-1880s Initial dam construction by S. Yuba Canal Co.

ca. 1908 Dam construction by PG&E

1913-1925 Lincoln Highway

1921-1927 Victory Highway

1956-present Old County Road

late 1970s Draw-down of Lake Van Norden

2012 Land acquired by Truckee Donner Land Trust

2013 Lake Van Norden and Meadow Assessment

Van Norden Meadow

HGM Map (UCD)

Van Norden Meadow

Review of Historical Aerial Photography: 6-11-20118-21-20058-7-19929-6-19838-31-19777-24-19738-2-19727-15-19666-27-1939

Review of Historical Maps: GLO 1866County Maps 1887, 1890, 1913USGS 1889, 1940, 1955 (photo revised 1979)TNF 1911

Channel Conditions Van Norden Watershed and Meadow

Watershed Area: 10.4 sq. mi.

Headwaters of:

• South Fork Yuba River

Tributaries:

• Upper Castle Creek

• “Lytton Creek”

Geology:

• Cretaceous crystalline rocks

• Tertiary extrusive volcanics

• Glaciated

Current Land Uses:

Interstate I-80, Ski Areas, UPRR

Channel Conditions Upper Castle Creek

Channel Conditions South Fork Yuba River

Habitat Lake Van Norden and Meadow

Special Status Species:Bog and Fen species, Botrychium and Sphagnum

VegetationVan Norden Meadow

Bird Species Present Lake Van Norden and Meadow

Bird Species Present Lake Van Norden and Meadow

Bird Species Present Lake Van Norden and Meadow

Bird Species Present Lake Van Norden and Meadow

Bird Species Present Lake Van Norden and Meadow

Bird Species Present Lake Van Norden and Meadow

Bird Species Present Lake Van Norden and Meadow

Bird Species Present Lake Van Norden and Meadow

Other WildlifeInvertebrates, Reptiles, Amphibians, Mammals

BathymetryExisting Conditions

50 acre-foot lake mapStorage volume = 190 ac-ft

Surface area = 86.7 ac

Bathymetry50 ac-ft Lake Volume Footprint

4-foot notch lake mapReq’d notch depth = 2.2 feet

Surface area = 30.8 acres

Bathymetry4-ft Notched Lake Volume Footprint

4-foot notch lake mapStorage volume = 13.2 ac-ft

Surface area = 11.8 ac

Evaluation of alternatives

Evaluation of alternativesAerial photography evaluation and interpretation

1966

Evaluation of alternativesAerial photography evaluation and interpretation

1977

Evaluation of alternativesAerial photography evaluation and interpretation

2011

Discussion