Workshop #3 : May 28, 8:30 am (BACK)

Introduction to PFC – A Function Based Riparian Assessment Method

Kenneth Mayben
Weatherford, TX                                     

Steve Nelle
Riparian Specialist
San Angelo, TX

Intro by Nelle
Soutwest Hydrology
PFC Vegetation
Wrap Up for PFC

Learning Objectives: Workshop participants will:

  1. Gain an introductory understanding of riparian function
  2. Learn the physical processes of function that provide the basis for riparian and stream values.
  3. Be introduced to the PFC method of riparian assessment and the 17 visual indicators of a properly functioning riparian area

Workshop Description:
This workshop will provide an introduction to the riparian assessment method known as PFC or Proper Functioning Condition.  This assessment method is widely used on all BLM land in the western states and has been successfully used on several streams in Texas.  The PFC method was developed by a team of experts including the National Riparian Service Team and is described in the BLM publication TR 1737-15.  The formal use of the PFC method requires a trained interdisciplinary team with expertise in hydrology, fluvial processes and vegetation.  As a training and education tool, PFC is useful to help the layman understand the interrelationship of hydrology, fluvial geomorphology and riparian vegetation.  The bases of PFC are the physical processes that produce the functionality of a riparian area.  Using the PFC definition, a properly functioning riparian area will have adequate vegetation, landscape formation, or large woody material to dissipate energy, reduce erosion, protect banks, trap sediment, build floodplains, store water, provide floodwater retention, provide groundwater storage and sustain baseflow.   When these physical processes are working properly, then the stream and riparian area are able to provide for many of the important values desired by society, such as water quality, sustained flows, fish and aquatic habitat, wildlife habitat, livestock forage, and recreational value.  The PFC method uses a 17-point Yes or No checklist to assess these functional processes.  A rating is determined by considering the answers to the checklist items. The three possible ratings are: Proper Functioning Condition; Functional At Risk; and Nonfunctional.  Information gathered during the assessment provides clues regarding reasons for any impairment and provides a basis for restoration and management.   The PFC method applies to perennial and intermittent (seasonal) streams but is not applicable to ephemeral drainages that lack contact with a water table.