Transcript Daum_2007.odp - Truckee River Info Gateway

Truckee River Water Quality: Current
Conditions and Trends Relevant to
TMDLs and WLAs
Prepared for:
Truckee Meadows Water Reclamation
Facility. City of Reno and City of
Sparks, Nevada
Prepared by:
Alan Jassby PhD, Ted Daum MS, and
Charles Goldman PhD, Ecological
Research Associates, Davis, CA.
Truckee River Info Gateway (TRIG)
www.truckeeriverinfo.org
• City of Reno
– Mahmood Azad, Program Manager
• City of Sparks
– Mike Brisbin, WQ Coordinator, TMWRF
• Ecological Research Associates
– Dr. Charles Goldman
– Dr. Alan Jassby
– Ted Daum (currently at EDAW, Inc.)
• UC Davis
– David Waetjen
Truckee River
Basin
Study Goals
• Provide a description of the
conditions and trends for TMDL water
quality constituents
• Estimate loads of these constituents
at key points in the Truckee River
• Relative impact of TMWRF effluent
compared with other sources
Regulatory Background
• Clean Water Act
– The Clean Water Act of 1972 (CWA) is the
primary federal law that governs and
authorizes water quality control activities by
the EPA as well as the states.
– The law requires point-source effluent limits
for industry and publicly owned treatment
works (POTWs) and water quality standards
for contaminants in surface waters.
Regulatory Background
• Section 303(d) Impaired Waters List
– Total Maximum Daily Load (TMDL)
– Waste Load Allocation (WLA)
• Nevada Division of Environmental Protection
(NDEP) Bureau of Water Quality Planning water
quality protection functions including:
– developing water quality standards for surface
waters, contained in the Nevada
Administrative Code (NAC)
Total Maximum Daily Load (TMDL)
• amount of loading that the water body can
receive and still meet water quality standards
• can also act as a plan to reduce loading of a
specific pollutant from various sources to
achieve compliance with water quality objectives
• Waste Load Allocations (WLA) - must include
an allocation of allowable loadings to point and
non-point sources, with consideration of
background loadings and a margin of safety.
Data Sources
•
Most data used in study from Truckee Meadows Water Reclamation
Facility (TMWRF) monitoring stations, 1985 – 2006. Names, station
codes, locations, and distance (km) from Lake Tahoe.
Truckee Meadows Water Reclamation Facility (TMWRF)
monitoring stations used in study
Truckee Meadows Water Reclamation Facility (TMWRF)
Steamboat Creek Upstream of TMWRF
USGS gage stations used in study, gage site numbers,
drainage areas (km2), and corresponding monitoring
stations for calculation purposes
Gaging Station Schematic and Associated TMWRF
Monitoring Station
TMDL-related Truckee River water quality constituents
(mg/l) at Lockwood Bridge during 1995 – 2006.
Distributions of Monthly Mean Concentrations at TMWRF Stations relative
to the Monthly Mean at mccarran, the Most Upstream Station 1995 - 2006
DIN:DRP molar ratios versus DRP at TMWRF
stations during summers of 1998 – 2006.
Seasonal distributions of total and inorganic N:P ratios at
TMWRF stations during 1995 – 2006
Monthly Averages of Daily Constituent Loads in
TMWRF Effluent
TMWRF Effluent Trends and Loads
Trends in TMWRF effluent concentrations and loads
during1995--2006.
Population of Washoe County and of Reno and Sparks
combined.
Monthly Average Nitrogen Fractions at Lockwood
Monthly Average P Fractions, TDS, and DOC at
Lockwood
River Trends in Water Quality Constituents 1995 2006
Mean Daily Loads of Water Quality Constituents (kg/day)
during 1998 – 2006.
Median Ratio of Daily TMWRF Loads to TMWRF +
mccarran + steamboat + ntd in Summers of 1998 – 2006.
Conclusions
• N Loadings Above Lockwood: Truckee
River > Steamboat Creek > TMWRF >
North Truckee Drain
• No trends in loading of any N fraction
since WLAs adopted despite increase in
service area population, likely due to
TMWRF N treatment advances
• Strong N limitation for plant growth,
especially downstream
Conclusions
• TN and TP loadings between wadsworth
and nixon, and between lockwood and
clark, exceed TMWRF effluent
contributions
• TP and DRP loadings from TMWRF have
increased since 1995. Increase similar to
population increase.
• TP and DRP loadings have also increased
upstream of TMWRF and in North Truckee
Drain
Conclusions
• Map lower watershed areas for potential N
and P sources, synoptic study to compare
contributions
• TMDL and WLA revisions should take into
account relevant timescales
– Integrated loading for Pyramid Lake impacts
– Median daily loading during summer for
nutrient loading to the Truckee River
TRIG and ERA Truckee River
Water Quality Report
• TRIG Potential
– Loading Calculations
– TMDLs and WLAs
– Contaminant Status and Trends
– Data Gaps
– Other