Problem 
As urban and rural growth continues, competition for clean water expands into stream areas previously capable of meeting local water-use demands.  Conflicts among instream and offstream users of streamflow increase as flows decrease.

Objective
The objectives of this research are to enhance understanding of summer low-flow conditions in the North Fork, South Fork, and Shenandoah Rivers, relate water availability to physical habitat needs of fish, and develop a relation for the availability of suitable fish habitat and instream flows.

Relevance and Benefits
As a result of the study, the counties and communities in the Shenandoah Basin should have a better knowledge of the water resources in the basin, the regional hydraulic system, and the effect of withdrawals and conservation measures on the ecology, agriculture, industry, and water supply.  The data and alternative condition analyses may be used for identification and compilation of the major instream-flow issues, development of the required multidisciplinary technical team to conduct more detailed studies, and develop basin specific habitat and flow requirements for aquatic life and water uses.

Approach
Flow data and biological data will be combined with depth and velocity of streamflow, cover type and bed-material size of numerous verticals at cross sections representing channel types. For the North Fork, hydraulic data were collected over a range of discharges by the USGS with the assistance of VPI. Hydraulic data were input to the RHABSIM model (River Habitat Simulation Software), a 1-dimensional water-surface profile model that uses stage-discharge ratings to simulate habitat conditions over a range of discharges. The modeling was used to determine the relation between habitat and flow. This information along with offstream user needs will allow the planning district more efficient allocation of water resources.

Publications and Presentations

September 2004
Report Published
Water-Quality Synoptic Sampling, July 1999: North Fork Shenandoah River, Virginia
http://pubs.usgs.gov/sir/2004/5153/

October 25, 2004
USGS Powerpoint presentation to the RWRPC Technical Advisory Committee
North Fork Instream Flow Study overview and South Fork proposed work

December 2004
USGS Fact Sheet (unpublished) MS Word
North Fork Instream Flow Study overview and South Fork proposed work

March 2005
USGS power point presentation to the RWRPC Technical Advisory Committee
North Fork Shenandoah River Results Application For the State Drought 
Assessment Plan

DEQ Drought Response Plan Documentation
http://www.deq.virginia.gov/waterresources/droughttac.html

June 7-8, 2005
Mid Atlantic Area Water Availability Workshop
University of Delaware Conference Center, Newark Delaware
Presentation with Alison Teetor
http://va.water.usgs.gov/delwkshp2005/index.htm
Accompanying Notes for USGS power point 


North Fork Instream Flow Study Poster Presented at the Water Availability Workshop
Habitat Availability During Low-Flow Periods on the North Fork Shenandoah River, Virginia 

Preliminary Results
December 10, 2003 
USGS Powerpoint presentation to the MIF Technical Advisory Committee with accompanying notes.