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Perspectives on Salinity Management CalDesal 2nd Annual Desalination Conference San Diego, CA – October 3, 2013
Jeff Mosher National Water Research Institute Fountain Valley, CA
} Removing Salt from Water Uses A Lot of Energy
} It is therefore, relatively expensive
} Prevention is much more cost effective (Colorado River, water softeners, Delta diversions from Sacramento River)
Courtesy: Rich Atwater (SCWC)
Southern California Salinity Coalition
l Formed in 2002 by: l Water and wastewater agencies and districts l Nonprofit
l Purpose: “Address the critical need to remove salt
from water supplies and to preserve water resources in California”
“More Water. Less Salt.”
SCSC Members
l Eastern Municipal Water District l Inland Empire Utilities Agency l Metropolitan Water District of Southern California l Orange County Sanitation District l Orange County Water District l San Diego County Water Authority l Sanitation Districts of Los Angeles County l Santa Ana Watershed Project Authority
SCSC Objectives
l Goals: l Elevate awareness of salinity-related
problems and issues
l Seek, promote, and support solutions
Observation
l Salinity may be the most under recognized water-quality problem facing California and the southwest
What is the issue?
l Salt levels increasing in: l Surface water and groundwater supplies l Wastewater and recycled water
l Causes: l Natural processes and l Intensive use of water:
l Agriculture practices l Land use practices l Commercial l Residential l Salt in water can result
in salt imbalance in a basin
Consequences
l Salt accumulation: l Degrades water quality l Limits the use of water for:
l Agriculture l Industrial uses l Municipal uses l Water recycling
l Financial impacts can be large l Cost of corrosion l Cost of treatment
Economic Impacts of Salinity
l MWD and Reclamation l Covers:
l Problems, impacts, and technology
l Management Strategies l “Action Plan”
l Also: l 1999 Salt Balance:
600,000 tons/year l Economic impacts
Action Areas from 1999 Study
1. Imported Water Source Control and Salinity Reduction Actions
2. Distribution System Salinity Management Actions
3. Collaborative Actions with other Agencies
4. Local Salinity Management Actions
MWD Salinity Policy
• Protect source supplies
• 500 mg/L Objective
• Optimize use of CR and SWP supplies
• Integrate W.Q. and quantity objectives
• Support regional regulatory and management actions
• Use the Salinity Management Action Plan
Southern California Area Office Challenges
• Providing Water for Future Needs
• Salinity Control for Effective Water Management
• Brine Concentrate Management
• Environmental Needs • Implementing the Colorado
River Plan • Implementing CALFED/Bay
Delta • Tribal Needs
Desalting and Concentrate Disposal
l Desalters: l Treat saline groundwater (new water source) l Tool for managing basin salinity
l Concern: disposal of concentrate l Brine line – great in you have one l Other options: costly and impractical
l Bureau of Reclamation Study (2009) l SoCal Regional Brine Management Study l SCSC co-sponsor www.usbr.gov/lc/socal/planning.html
Project – Salt Management Guide
l Salt Management Guide for Landscape Irrigation with Recycled Water (CD-ROM)
P.I. Kenneth Tanji, UC-Davis
l Objectives: l Reluctance by consumers to use recycled
water for landscaping l Inform the public and landscape industry
about using recycled water l Develop salt management guidelines (best
practices) for landscape professionals
Website: www.SalinityManagement.org
Projects – Water Softeners
l Rebate programs l Santa Clarita Valley Sanitation
District l “Automatic Water Softener Rebate
Program” l Inland Empire Utilities Agency
l “Salinity Reduction Program l Fact sheet:
l “Salinity and Water Softeners” l Evaluation of Alternatives to
Water Softeners l Evaluation study (Peter Fox – ASU)
Project: Salt Management Planning
l CA Recycled Water Policy (Feb 2009) l Salt/Nutrient Management plans:
l Stakeholder-driven and consensus-based
l SCSC Project: l Salt Management Plan Guidelines for San
Diego Region
l Collaboration: SCSC, San Diego County Water Authority, and the Regional Board
Salt Management Plans
l Potential Benefits to Agencies: l Influence Basin Plan objectives and policies
l Protect/enhance groundwater quality
l Increase groundwater production/yield
l Enhance recycled water opportunities
l Address recycled water compliance issues
Source Control
l Created in 1973 l CO River basin
states l Coordinate salinity
activities with federal agencies
E&O Commi)ee 6a April 2013
Deep Well Injec;on
Photo courtesy of CRBSCF
Dolores River
Montrose County, Colorado
Deep Injec)on Well Shallow Extrac)on Wells
E&O Commi)ee 6a April 2013
Whitse) Intake at Lake Havasu
0
100
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TDS (m
g/L)
Southern California Salinity Management Study Update
Partnership: USBR, MWD, and SCSC
Salt Update Project “Objectives”
1. Outreach Workshop, identifying challenges of Southern CA salinity management (SCSC)
2. Update the USBR salinity economic impact model and evaluate regional economic impacts (USBR)
3. Update California salinity conditions and promote effective regional salinity management (SCSC)
4. Assess MWD future operational capability to deliver low salt water (MWD)
Objective 1: Salinity Management Workshop
l June 2012 l Revisit salinity
challenges and identify potential solutions
l Attendees were water industry stakeholders
l Available at: www.socalsalinity.org
Q7. What is your agency/organization's specific interest in salinity management?
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Q10. Do you have challenges with specific components of salinity (e.g., chloride)?
Yes No 0%
10%
20%
30%
40%
50%
l Challenges include: l Chloride l Groundwater basin water quality objectives l Agricultural irrigation uses l Boron, sulfate, and bromide
Q12. What FUTURE strategies are you considering (or would you consider) to better manage salinity?
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Salinity Challenges
l Salinity is a complex problem l Understanding stakeholders l Under-recognized water quality problem
l Source control in watersheds l Basin planning l Region-wide solutions
l Treatments AND best practices l Changes in policies and regulations l Concentrate management
Challenges
l Reality of salinity: l Urban issues vs. rural issues l Short-term practices vs. long-term impacts l Crisis vs. slow deterioration l Complexity of solutions l Fairness (of who incurs costs) vs. effectiveness (of
solutions) l Changing knowledge (understanding the problem)
vs. persistent policy (current practices and regulations)
