California Healthy Watersheds Assessment

California Healthy Watersheds AssessmentStatus UpdateMarch 7, 2013

U.S. EPA Healthy Watersheds Initiative

EPA HWI website: www.epa.gov/healthywatersheds

Overarching goals of the Initiative: Protect and maintain healthy watersheds,

and increase their numbers over time. Raise the visibility and importance of

protecting high quality waters.

Emphasis is on the protection of: Landscape connections Watershed processes and functions

Healthy Watershed Attributes

Healthy Watershed

s

Landscape Condition

Habitat Condition

Hydrologic Condition

Geomorphic Condition

Water Quality

Biological Condition

Healthy Watersheds Assessments Methodology

Select indicators that represent

the six attributes of watershed

health

Calculate or estimate the indicators for

each watershed

Data acquisition and review

Create a multimetric

index of watershed

health

Select indicators that represent

watershed vulnerability

Calculate or estimate the indicators for

each watershed

Create a multimetric

index of watershed

vulnerability

Establish and prioritize

management actions

Watershed Health

Watershed Vulnerability

Project Goals & Objectives

Screening-level assessment to rank watersheds on a statewide basis according to their relative condition as defined by indicators of: Landscape Condition Hydrologic Condition Habitat Condition Geomorphic Condition Water Quality Biological Condition

Combine with a vulnerability assessment to help set management priorities

Timeline

November 2011 – Draft Technical Approach

February 2012 – Initial Selection of Indicators

August 2012 – In-person Project Meeting to Finalize Technical Approach and Selection of Indicators

February 2013 – Draft Results

April 2013 – Draft Report

May 2013 – Final Report and Data Delivery

Outcome from August Meeting

Partnership selected: Watershed Condition Indicators:

Watershed structural attributes that drive aquatic ecosystem processes and for which spatially continuous landscape-level data are available.

Aquatic Ecosystem Health Indicators: Aquatic ecosystem attributes for which high

quality data representative of the various ecoregions in California are available at discrete sampling locations

Watershed Condition Indicators

Percent Natural Land Cover in the Active River Area

Percent Natural Land Cover in the WatershedPercent Natural Land Cover in Headwater

AreasSoil Infiltration Capacity Relative Risk of Excess Sediment Production Number of Road/Stream CrossingsDam Storage RatioArtificial Drainage

Aquatic Ecosystem Health Indicators

Attribute IndicatorNumber of

Locations with Data


Large Flood Flow Alteration 947Small Flood Duration Alteration 947Small Flood Date Alteration 947Small Flood Frequency Alteration 947Alteration in Rate of Fall After High Flow Events

947


Physical Habitat Multimetric Index 632

Water Quality

Nitrate 927

Turbidity 1,001

Conductivity 1,539

pH 1,422

Temperature 1,606

Habitat Condition CRAM 848


Combined Stream Condition Index 1,698

Analysis of Aquatic Ecosystem Health Indicators

Select Indicator

s

Statistical Analysis

Develop Models

Predict Indicator Values

for Entire State

Roll up into

Index

Initial Model Performance

Attribute Indicator

Training

R2/AUC*

Validation

R2/AUC*


Large Flood Flow Alteration 0.58* 0.62*Small Flood Duration Alteration 0.59* 0.50*Small Flood Date Alteration 0.57* 0.58*Small Flood Frequency Alteration 0.64* 0.61*Alteration in Rate of Fall After High Flow Events 0.65* 0.60*


Physical Habitat Multimetric Index0.9 0.46

Water Quality

Temperature 0.75 0.46

pH 0.44 0.19

Conductivity 0.86 0.72

Turbidity 0.29 0.02

Nitrate 0.69 0.51

Habitat Condition California Rapid Assessment Method Index 0.76 0.53Biological Condition

Combined Stream Condition Index0.72 0.49

CRAM Wetland Index

Represents habitat condition attribute

Based on California Rapid Assessment Method data.

CRAM Wetland Index

Relative size of red dot represents percent error in predictions at locations with observed data.

CSCIRepresents

biological condition attribute

Based on new Combined Stream Condition Index (CSCI)

CSCIRelative size of red

dot represents percent error in predictions at locations with observed data.

Physical Habitat IndexRepresents

geomorphic condition attribute

Based on current work being conducted by Southern California Coastal Water Research Project

Physical Habitat IndexRelative size of red

dot represents percent error in predictions at locations with observed data.

Multimetric Index

Predicted values of each Aquatic Ecosystem Health Indicator were normalized to a scale of 0-1 and averaged together for each of: Hydrologic Condition Geomorphic Condition Water Quality Habitat Condition Biological Condition

Similarly, the Watershed Condition Indicators were normalized to a scale of 0-1 and averaged together to obtain a Watershed Condition Index.

Watershed Condition Percent Natural Land Cover

in the Active River Area

Percent Natural Land Cover in the Watershed

Percent Natural Land Cover in Headwater Areas

Soil Infiltration Capacity

Relative Risk of Excess Sediment Production

Number of Road/Stream Crossings

Dam Storage Ratio

Artificial Drainage Area

Hydrologic Condition Large Flood Flow

Alteration

Small Flood Duration Alteration

Small Flood Date Alteration

Small Flood Frequency Alteration

Alteration in Rate of Fall After High Flow Events

Geomorphic ConditionPhysical Habitat

Multimetric Index

Habitat ConditionCalifornia Rapid

Assessment Method Index

Water QualityTemperature

pH

Conductivity

Turbidity

Nitrate

Biological ConditionCombined Stream

Condition Index

Aquatic Ecosystem Health



Water Quality

Habitat Condition



Climate Change Vulnerability Projected change in precipitation Projected change in temperature Projected change in baseflow Projected change in monthly snowpack Projected change in wildfire severity Projected change in monthly surface runoff

Land Use Vulnerability Fire Regime Condition Class Projected Land Cover Change

Water Use Vulnerability Current Water Demand

Climate Change Vulnerability

Projected change in precipitation

Projected change in temperature

Projected change in baseflow

Projected change in monthly snowpack

Projected change in wildfire severity

Projected change in monthly surface runoff

Land Use Vulnerability

Fire Regime Condition Class

Projected Land Cover Change

Water Use Vulnerability

Current Water Demand


Climate Change Vulnerability

Land Use Vulnerability

Water Use Vulnerability

Outcomes from Feb. 14Call with HSP

Identification of thresholds or weights for the various indicators will require a stakeholder process that is not feasible under this project timeline.

Results will be reported at the scale of analysis (135,255 stream reach catchments). This allows for rollup to any larger scale desired.

Desert ecoregion will be evaluated based on watershed condition indicators only.

Next Steps

Refine and finalize modeling.

Produce a draft final report for review by HSP (4/8/2013).

Produce revised final report and deliver data (5/13/2013): Geodatabase of all input data and model

outputs.

Discussion

What are the Council recommendations for presenting the results in the final report and the Healthy Streams Portal?

Documents

California Healthy Watersheds Assessment