Septic Nitrate Baseline Data and
Impact Assessment Study for
Washoe County
Phase II: In-Depth Analysis of Prioritized Study Areas,
Baseline Dataset Creation, & Impact Assessment
Northern Nevada Water Planning Commission
August 3, 2016
NNWPC Item 7
1
Project Objectives
• In depth analysis to determine potential impact
to water quality
• Nine prioritized study areas identified in Phase I
• Revisit Washoe Valley, Cold Springs, and
Heppner
• 307 wells sampled throughout 12 study areas
• Analyzed for nitrate, chloride and TDS
• Water level and water quality parameters
2
Water Quality Results
4 study areas recorded wells over MCL of 10 mg/L
Study Area
Average Nitrate (mg/L)
Maximum Nitrate (mg/L)
Ambrose
Cold Springs
Geiger Grade
Heppner
Hidden Valley
Huffaker
Island 18
Mogul
Mt Rose
Pleasant Valley
Verdi
Washoe Valley
0.88
2.75
1.54
4.53
0.23
1.98
0.71
0.70
3.81
2.26
1.72
7.02
2.10
6.10
6.70
19.00
0.94
9.10
1.60
3.60
10.00
7.10
10.00
50.00
4
Washoe Valley
Heppner
Nitrate Informational Mailings
• July 2016: 5,000 letters mailed to all domestic
well owners within 12 study areas
• Nitrate informational and resource guide
• Summary of nitrate concentrations in area
• Provided local contacts for questions or
additional services and information
7
Recommendations
• Contract extension or new Interlocal Agreement
• $91,000 remaining in budget
• Public outreach component
• Interactive public sessions [ex. CAB meetings]
• Additional mailings to well owners outside of the 12
study areas
8
Questions?
9