California Department of Fish and Wildlife
Aquatic Biological Assement

EMAP  |  Sites  |   Historical Overview

EMAP (1999-2004) - Western Pilot - California

Environmental Monitoring and Assessment Program (EMAP)

In the spring of 1999, DFG entered into a cooperative agreement with the EPA to serve as the primary organization conducting the field and laboratory efforts for EPA's EMAP Western Pilot study.

EMAP overview

The Environmental Monitoring and Assessment Program (EMAP) is a research program to develop the tools necessary to monitor and assess the status and trends of national ecological resources. EMAP's goal is to develop the scientific understanding for translating environmental monitoring data from multiple spatial and temporal scales into assessments of current ecological condition and forecasts of future risks to our natural resources.

EMAP aims to advance the science of ecological monitoring and ecological risk assessment, guide national monitoring with improved scientific understanding of ecosystem integrity and dynamics, and demonstrate multi-agency monitoring through large regional projects. EMAP develops indicators to monitor the condition of ecological resources. EMAP also investigates designs that address the acquisition, aggregation, and analysis of multiscale and multitier data.

Western Pilot

The purpose for this western study is to further advance the science of monitoring and to demonstrate the application of core tools from EMAP in monitoring and assessment across the West. The Western Geographic Study will serve to advance both the science of monitoring and the application of monitoring to policy, provide an opportunity to push the science and its application to new levels, both in terms of the type of systems addressed (mountainous and arid systems) and the size of the region covered (essentially one third of the conterminous U.S.), and demonstrate the application of EMAP designs in answering the urgent and practical assessment questions facing the western EPA Regional Offices, while framing these unique studies in a methodology that can be extended to the entire nation.

The primary objectives of the Western Pilot Study (EMAP-WP), the surface waters component of the Western Geographic Study are to:

· Develop the monitoring tools (biological indicators, stream survey design, estimates of reference condition) necessary to produce unbiased estimates of the ecological condition of surface waters across a large geographic area (or areas) of the West; and

· Demonstrate those tools in a large-scale assessment.

The goal of EMAP-WP is to provide answers to three general assessment questions:

1. What proportion of stream and river miles in the U.S. are in acceptable (or poor) biological condition?

2. What is the relative importance of potential stressors (habitat modification, sedimentation, nutrients, temperature, grazing, timber harvest, etc.) in streams and rivers across the West?; and

3. With what stressors are streams and rivers in poor biological condition associated?

The resource population of interest for EMAP-WP are all perennial streams and rivers as represented in EPA's River Reach File (RF3), with the exception of the "Great Rivers" (the Columbia, Snake, Colorado and Missouri Rivers). The pilot study will utilize an EMAP probability design to select sites which are statistically representative of the resource population of interest. This will allow one to extrapolate ecological results from the sites sampled to the entire population. A comprehensive set of ecological indicators will be implemented in a coarse survey of streams and rivers across all of the West (the conterminous portions of EPA Regions 8, 9, and 10), as well as in several more spatially-intensive "focus areas" in each Region. Sample sizes (i.e., numbers of stream sites) have been chosen to allow eventual estimates of condition to be made for each state, each Regional focus area, numerous aggregated ecological regions (e.g., mountainous areas of the Pacific states, the Southern Basin and Range, etc.), major river basins, and many other potential geographic classifications.