Landscape Change in the Napa River Watershed, 1800–2002: Implications for the Restoration of In-Stream, Floodplain, and Valley Floor Habitat

Grossinger, R., Striplen, C., Brewster, E., San Francisco Estuary Institute

and L. Collins, Watershed Sciences

CALFED Science ConferenceJanuary 16, 2003

Project Goals– a map of the pre-European impact fluvial system

• extent of floodplain• location of distributary systems, side channels, riparian habitat flood control, stream restoration, fisheries recovery

– a map of the pre-European impact distribution and abundance of valley floor habitats• oak savanna• seasonal wetland/vernal pools• native grassland conservation planning (identifying remnants, proportional representation, designing corridors and

mosaics)

– land use history• spatial extent and duration of grazing, logging, ditching, etc. identify early uses which may have ongoing effects

– community-participatory processacquire needed datagreater shared understanding of how the current landscape has evolved and its potential for

restoration

Presentation Outline

1. Approach• Partnerships • Issues of scale

2. Methods• 19th-century Historical Documents• Early Aerial Photography• Mapping of Present-day Ecological Remnants

3. Preliminary Findings — methodological and technical• Pleasures and Pitfalls of Historical Sources• Discovery of Counter-Intuitive Changes• Substantial Variation in Historical Landscape within a Small Area (

variation in present-day geomorphic controls)

Napa River Watershed Historical Ecology

Project endorsed and/or funded by:

• Napa Valley Vintners Association• Land Trust of Napa County• Mead Foundation• Mennen Environmental Foundation• Napa County Planning Department • Napa County Resource Conservation District• SF Bay Region Water Quality Control Board• California Department of Fish and Game• Army Corps of Engineers• CALFED Watershed Program

Napa River Watershed Historical Ecology Project Collaborators

Shari Gardner and Chris Malan, Friends of Napa River – local project coordinators

Elise Brewster, Brewster Design Arts – archival research, historical cartography

Mike Champion, Napa RCD – archival research

Sarah Pearce, SFEI – fluvial geomorphology

Laurel Collins, Watershed Sciences – fluvial geomorphology

Chuck Striplen, SFEI and UCB – pre-European land management

Josh Collins, SFEI – wetlands geomorphology

Lester McKee, SFEI – watershed processes

Jake Ruygt, Napa County Botanist – local plant community ecology

Robin Grossinger, SFEI – historical ecology/landscape history

Thomas Burns, GIS Mapping and Analysis – historical photogrammetry

Eric Wittner, SFEI – GIS development

1. Approach• Partnerships • Issues of scale

2. Methods• 19th-century Historical Documents• Early Aerial Photography• Mapping of Present-day Ecological Remnants

3. Preliminary Findings — methodological and technical• Pleasures and Pitfalls of Historical Sources• Discovery of Counter-Intuitive Changes• Substantial Variation in Historical Landscape within a Small Area (

variation in present-day geomorphic controls)

Project Scale and Corresponding TopicsScale: Region Major

WatershedsTributary Watersheds

Area: ~1000 sq. mi 100-500 sq. mi. 5-20 sq. mi.

Focus on: • tidal processes and lower reaches of streams

• fluvial processes of valley floor

• relationship between tributaries and main channel

• effects of flood control, ditching, drainage

• hillslope processes

• effects of grazing, logging, fire

Key Historical Sources

Federal Maps, Spanish Maps,

+ Aerial Photos,

Local Maps, Written Accounts

+ Landscape Photos, Local Interviews

Sulphur

SodaSoda

Carneros

Napa River Watershed

San Francisco Bay

1. Approach• Partnerships • Issues of scale

2. Methods• 19th-century Historical Documents• Early Aerial Photography• Mapping of Present-day Ecological Remnants

3. Preliminary Findings — methodological and technical• Pleasures and Pitfalls of Historical Sources• Discovery of Counter-Intuitive Changes• Substantial Variation in Historical Landscape within a Small Area (

variation in present-day geomorphic controls)

1. Approach• Partnerships • Issues of scale

2. Methods• 19th-century Historical Documents• Early Aerial Photography• Mapping of Present-day Ecological Remnants

3. Preliminary Findings — methodological and technical• Pleasures and Pitfalls of Historical Sources

– Importance of Pre-1940s Data– Potentials for Misinterpretation

• Substantial Variation in Historical Landscape within a Small Area ( variation in present-day geomorphic controls)

• Discovery of Counter-Intuitive Changes

USCS 1860 USCS 1861

ca. 1940 Aerial photomosaic 1993 Aerial photomosaic

Lower Sulphur Creek

Products from Napa River Watershed Landscape Change Studies

• Historical Ecology Component of Napa Watershed Exhibit at the Napa Valley Museum -- opens January 25

• Napa River Sediment TMDL Baseline Study: Geomorphic Processes and Habitat Form and Function in Soda Creek -- ~ 1 month

• Stewardship Support and Watershed Assessment in the Napa River Watershed: A CALFED Project (Sulphur and Carneros Creeks) -- ~ 6 months

• Napa Valley at the Time of European Contact GIS and Report -- ~ 1 year (pending funding)

www.sfei.org