Post on 09-May-2023
Water Reuse Regulations
Regulation 84
Domestic wastewater– Toilets
– Kitchen sinks
– Bathroom wastewater
– Laundry wastewater
More organic matter
More risk for pathogen growth
3 “categories” of treatment
Regulation 86
Graywater– Only
Bathroom sinks
Bathroom showers and baths
Laundry machines
Laundry room sinks
Less organic matter
Less risk for pathogen growth
4 “classes” of graywater
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Overview of Reg 84
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Has been regulated since 2000– Treaters – treat non-potable reclaimed water
– Users – reclaimed water is provided for use on site from treater 26 treaters, ≈ 500 users/sites
15 approved uses
Water rights needed to reuse
Up and coming Reg 84 changes – Edible crops and hemp irrigation
Commercially processed crops versus non-commercial
Reclaimed Water Treatment
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Category 2Category 1 Category 3
Treatment (also BMPs)
As human exposure increases, so does
treatment
Regulation 84 Overview Category General Pathogenic TSS/Turbidity Allowed Uses
Category 1 Secondary w/
disinfection
E. coli monthly
mean
126/100mL
single sample
max
30 mg/L daily
max (TSS)
Evaporative
and non-
evaporative
industrial
processes,
Landscape
irrigation
(restricted), zoo
operations &
Non-food crop
irrigation and
silviculture
Category 2 Secondary w/
filtration and
disinfection
E. coli monthly
mean
126/100mL and
235/100 mL
single sample
max
≤ 3 NTU
monthly mean
and ≤ 5 NTU in
more than 5 %
samples in
month
Same as
Category 1,
landscape
irrigation
(unrestricted),
commercial
laundries,
automated and
manual non-
public vehicle
washing &
nonresidential
fire protection
Category 3 Secondary w/
filtration and
disinfection
E. coli/mL non
detect in ≥ 75 %
per month and
126/mL single
sample max
≤ 3 NTU
monthly mean
and ≤ 5 NTU in
more than 5 %
samples in
month
Same as
Category 2,
resident
controlled
landscape
irrigation,
residential fire
protection
• E. coli, TSS and
turbidity
• Uses + best
management
practices
• Guidance & policies
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Current Colorado uses
Irrigation
Commercial
Industrial
Fire protection
Agricultural ▪ Not human consumption
▪ Until we update the regulation
Best management practices
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Recent Rule Making Hearing
2018 Rulemaking
hearing
– Added toilet and
urinal flushing
Cross connection risk
– Filtration and
disinfection for
Category 3 toilet and
urinal flushing
– Localized treatment
systems
Log reduction targets
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Next Steps
Legislation
– Stakeholder work for
2019 Rulemaking
Edible crops
– Categories 2 & 3
Hemp
– Categories 1, 2 & 3
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Localized Non-potable Systems
Onsite reuse– Graywater
– Blackwater Reduce discharges with
reuse
Graywater (Reg 86)– NSF 350 certification
Stakeholder process underway
Blackwater (Reg 84)– Higher treatment
Log reduction targets
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Localized Non-potable Systems
Advantages
Municipality does not pay
Efficient water use
– Right water for the right
use
Reduce discharges to
surface and groundwater
– By what amount?
Automated
– With little oversight
– With backup potable
Disadvantages
Expensive?
– Site specific
– Graywater vs. blackwater
reuse
Other source waters
Socially acceptable?
Compliance and
enforcement
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Municipal Non-potable Systems
Advantages
Reach more
customers/expand
– Cheaper rate for
customers
Mainstream reuse
New development
Disadvantages
Costs to municipality
– Often similar to potable
aside from treatment
Socially acceptable?
Compliance and
enforcement
More oversight/operators
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Direct Potable Reuse
Again, water rights
needed
Purified
Pipe to pipe
Engineered buffer
Higher need for
public acceptance
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Direct Potable Reuse
Colorado
– Historic pilot project
Denver Water
10 years
Health effects study
– Recent demonstration
project
– Workgroup
Developing framework
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Direct Potable Reuse
National– Pilots
– Approval to move forward in CA
– Regs being developed in TX
– Public outreach Beer and wine!
International– Regions in Southern Africa and elsewhere
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Conclusions
Reuse is an option
– To maximize water efficiency
– To reduce discharges
– To upgrade current facilities (w/ potential
ROI)
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Contact Information
Brandi Honeycutt 303-692-6357
Brandi.Honeycutt@state.co.us
https://www.colorado.gov/pacific/cdphe/
wq-reclaimed-water-stakeholders
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