Building Water Reuse from
the Ground Up:
Lessons Learned over 4 Decades
Earle Hartling
Water Recycling Coordinator
Los Angeles County
Sanitation Districts
⚫ Serving 5.6 million people in 78 cities
⚫ One ocean disposal facility
⚫ 10 water reclamation plants
Los Angeles County
Sanitation Districts
⚫ Serving 5.6 million people in 78 cities
⚫ One ocean disposal facility
⚫ 10 water reclamation plants
Recycled Water Program –
Where we came from
0
100
200
300
400
500
600
1930 1940 1950 1960 1970 1980 1990 2000 2010 2019
MGD
Recycled and Discharged to River
Recycled and Beneficially Reused
Ocean Disposal
Post-WWII
Whittier Narrows
Other JOS WRPs
76-77 drought
86-92 drought
1998 El Niño 2006-
drought
1989 Peak
Recycled Water Program –
Where we came from
0
100
200
300
400
500
600
1930 1940 1950 1960 1970 1980 1990 2000 2010 2019
MGD
Recycled and Discharged to River
Recycled and Beneficially Reused
Ocean Disposal
Post-WWII
Whittier Narrows
Other JOS WRPs
76-77 drought
86-92 drought
1998 El Niño 2006-
drought
1989 Peak
Recycled Water Program –
Where we are now
⚫ High quality recycled/reclaimed water
⚫ 100,000 acre-feet/year beneficially used
⚫ 950 individual sites
⚫ Over 20 distribution systems
Recycled Water Program –
Where we are now
⚫ High quality recycled/reclaimed water
⚫ 100,000 acre-feet/year beneficially used
⚫ 950 individual sites
⚫ Over 20 distribution systems
Direct Nonpotable Uses
1995 Beneficial Plan
⚫ Physical Issues
⚫ Regulatory Compliance
⚫ Institutional Arrangements
⚫ Monetary Considerations
⚫ Public Acceptance
Physical Issues
⚫ Have technical/engineering solutions
⚫ Generally deal with either:
• Quantity
• Quality
Recycled Water
Supply vs. Demand
0
20
40
60
80
100
120
140
160
180
1960 1970 1980 1990 2000 2010 2019
REUSED
PRODUCED
MGD
Recycled Water
Supply vs. Demand
0
20
40
60
80
100
120
140
160
180
1960 1970 1980 1990 2000 2010 2019
REUSED
PRODUCED
MGD
JOINT OUTFALL SYSTEM
Annual Average Effluent Flows
300
320
340
360
380
400
420
440
460
480
500
2000 2005 2010 2015 2019
MG
D
Problem –
Daily Supply/Demand Offset
0
5
10
15
20
25
30
358:0
0 A
M
10:0
0 A
M
Noo
n
2:0
0 P
M
4:0
0 P
M
6:0
0 P
M
8:0
0 P
M
10:0
0 P
M
Mid
nig
ht
2:0
0 A
M
4:0
0 A
M
6:0
0 A
M
Supply
Demand
Theoretical WRP vs.
Hypothetical Reuse System
Solutions – Demand Side
Daily Operational Storage
Solutions – Demand Side
Daily Demand Shift
Solutions – Supply Side
Flow Equalization
Solutions – Supply Side
Flow Equalization
Problem –
Seasonal Supply vs. Demand
0
1
2
3
4
5
6
7
8
MG
D
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Supply
Demand
Pomona WRP – 2018 Flows
Solution – Seasonal Storage
Solution – Seasonal Storage
Solution –
Groundwater Recharge
Problem –
Recycled Water Quality
⚫ Minimum treatment levels
⚫ Microbial levels
⚫ Maximum Contaminant Levels (MCLs)
• Chemicals of Emerging Concern (CECs)
⚫ Salinity
Solution –
Minimum Treatment Level
Solution –
Microbial Quality
⚫ Generally 90% total coliform non-detects
⚫ 7-day median total coliform < 2
⚫ No viable Giardia or Cryptosporidium
⚫ 3 virus in 1,152 samples, 1.6 million liters
Solution – MCLs
⚫ Drinking water standards
⚫ All Primary MCLs are met:
• Heavy metals
• Trace organics
• Radioactivity
• Minerals
• Nitrogen
⚫ Secondary MCL for turbidity
Solution – MCLs
⚫ Drinking water standards
⚫ All Primary MCLs are met:
• Heavy metals
• Trace organics
• Radioactivity
• Minerals
• Nitrogen
⚫ Secondary MCL for turbidity
Solutions – Salinity
Demand Side
⚫ Reconfigure landscape plants
⚫ Modify irrigation schedule
⚫ Apply soil treatments
⚫ Rebalance cooling tower chemicals
Solutions – Salinity
Supply Side
⚫ High TDS sewage diverted around WRPs
• 500-800 mg/L TDS at WRPs
• 1,500 mg/L TDS at ocean disposal plant
⚫ Industrial waste pretreatment
⚫ Advanced treatment via RO
Regulatory Compliance
⚫ Most recycled/reclaimed regulations
originated in California – Title 22
⚫ Treatment levels and effluent quality
⚫ On-site requirements
Regulatory Solutions –
Facilities Identification
Regulatory Solutions –
Best Practices
Regulatory Solutions –
Supplemental Water
Institutional Arrangements
Highly segmented and complex water
supply hierarchy in Southern California
⚫ City water departments
⚫ Municipal water districts
⚫ Mutual water companies
⚫ Investor-owned utilities
Institutional Arrangements
Highly segmented and complex water
supply hierarchy in Southern California
⚫ City water departments
⚫ Municipal water districts
⚫ Mutual water companies
⚫ Investor-owned utilities
Institutional – Solutions
⚫ Easements
Institutional – Solutions
⚫ Easements
⚫ Shared facilities
Institutional – Solutions
⚫ Easements
⚫ Shared facilities
Institutional – Solutions
⚫ Easements
⚫ Shared facilities
Cal Poly, University
Forest Lawn Cemetery
Institutional – Solutions
⚫ Easements
⚫ Shared facilities
⚫ Interagency coordination
• Service duplication
• “Stay in your lane”
Institutional – Solutions
⚫ Easements
⚫ Shared facilities
⚫ Interagency coordination
• Service duplication
• “Stay in your lane”
Recycled Water Producer
Regional Water Distributor
Retail Water Provider
Reuse SiteEnd User
Monetary Considerations
⚫ Economic Analysis – Should it be done?
⚫ Financial Analysis – Can it be done?
Monetary Considerations
⚫ Water pricing
⚫ Future water costs
⚫ Alternative financing
• Parcel charges
• Low interest loans/grants
• Strategic partnerships
Public Acceptance – Problems
⚫ Perceived health risks – “yuck” factor
⚫ Growth inducement
⚫ Special interests
Public Acceptance – Problems
⚫ Perceived health risks – “yuck” factor
⚫ Growth inducement
⚫ Special interests
Public Acceptance – Solutions
⚫ Accessible technical information
⚫ Public “information”, not “education”
⚫ Qualified expert testimony
⚫ Outside allies
⚫ Community supporters
Public Acceptance – Solutions
⚫ Project website
⚫ News media
⚫ Social media
⚫ Speakers bureau
⚫ Facility tours
Questions?