CWEA - ADVANCED WATER
TREATMENT QUESTIONS AND
ANSWERS WITH SOLUTIONS 2024
Indirect Potable Reuse (IPR) - ANSWER The blending of advanced treated, recycled or reclaimed water
into a natural water source (environmental barrier) that could be used for drinking (potable) water after
further treatment.
Direct Potable Reuse (DPR) - ANSWER Process of treating wastewater to drinkable standards and
returning it to the raw water supply (distribution system) without the use of an environmental buffer.
Rather than mixing the treated water into an aquifer or reservoir
What has led to the research of Advanced Water Treatment? - ANSWER Strict effluent discharge limits
are pushing the development of treatment technologies.
Most wastewater reuse is? - ANSWER Unplanned and indirect reuse (IPR)
What is Fit for purpose? - ANSWER It is reclaimed wastewater that is treated to specific criteria and is
reused for purposes according to its treatment.
What are the AWT processes? - ANSWER 1. Microfiltration / Ultrafiltration
2. Reverse Osmosis / Nanofiltration
3. Advanced Oxidation (AOP)
4. Biological Aerated Filtration
5. Stabilization
6. Disinfection
What is the Stabilization Process? - ANSWER Adding nutrients to the treated water so that it wont pull
from pipes and etc.
How many days does IPR treated wastewater effluent need to be in Reservoir or Basin before entering
Water Treatment Facility? - ANSWER 30 days
, What does Log Removal Values measure? - ANSWER The effectiveness of the treatment processes. The
are determined by taking the log of pathogen concentration in the influent and effluent after treatment.
What are the 3 water quality requirements? - ANSWER 1. Nutrients
2. Aesthetics
3. Risk to human health, such as pathogen removal
What are our primary sources of water? - ANSWER Surface Water and Ground Water.
During Indirect Potable reuse, how long must water stay in a natural body of water before being used for
drinking water? - ANSWER 30 days.
Who dictates wastewater reuse? - ANSWER The State sets their regulations. EPA is not involved.
Who regulates the drinking water? - ANSWER Safe Drinking Water Act.
What are the California Reuse Regulations? - ANSWER A 12-10-10 log removal for Viruses,
Cryptosporidium and Giardia.
What can we use to disinfect water? - ANSWER Chlorine, ozone, and UV.
Benefits of Advanced Oxidation Process? - ANSWER Removed Total Organic Carbons and creates a
barrier for microorganisms.
How much Total Organic Carbon (TOC) and Conductivity can Reverse Osmosis remove? - ANSWER <
0.5mg/l TOC and 250mg/l conductivity.
MF, RO, UV/H2O2 is an example of what? - ANSWER MULTIPLE BARRIER TO PATHOGENS
TREATMENT QUESTIONS AND
ANSWERS WITH SOLUTIONS 2024
Indirect Potable Reuse (IPR) - ANSWER The blending of advanced treated, recycled or reclaimed water
into a natural water source (environmental barrier) that could be used for drinking (potable) water after
further treatment.
Direct Potable Reuse (DPR) - ANSWER Process of treating wastewater to drinkable standards and
returning it to the raw water supply (distribution system) without the use of an environmental buffer.
Rather than mixing the treated water into an aquifer or reservoir
What has led to the research of Advanced Water Treatment? - ANSWER Strict effluent discharge limits
are pushing the development of treatment technologies.
Most wastewater reuse is? - ANSWER Unplanned and indirect reuse (IPR)
What is Fit for purpose? - ANSWER It is reclaimed wastewater that is treated to specific criteria and is
reused for purposes according to its treatment.
What are the AWT processes? - ANSWER 1. Microfiltration / Ultrafiltration
2. Reverse Osmosis / Nanofiltration
3. Advanced Oxidation (AOP)
4. Biological Aerated Filtration
5. Stabilization
6. Disinfection
What is the Stabilization Process? - ANSWER Adding nutrients to the treated water so that it wont pull
from pipes and etc.
How many days does IPR treated wastewater effluent need to be in Reservoir or Basin before entering
Water Treatment Facility? - ANSWER 30 days
, What does Log Removal Values measure? - ANSWER The effectiveness of the treatment processes. The
are determined by taking the log of pathogen concentration in the influent and effluent after treatment.
What are the 3 water quality requirements? - ANSWER 1. Nutrients
2. Aesthetics
3. Risk to human health, such as pathogen removal
What are our primary sources of water? - ANSWER Surface Water and Ground Water.
During Indirect Potable reuse, how long must water stay in a natural body of water before being used for
drinking water? - ANSWER 30 days.
Who dictates wastewater reuse? - ANSWER The State sets their regulations. EPA is not involved.
Who regulates the drinking water? - ANSWER Safe Drinking Water Act.
What are the California Reuse Regulations? - ANSWER A 12-10-10 log removal for Viruses,
Cryptosporidium and Giardia.
What can we use to disinfect water? - ANSWER Chlorine, ozone, and UV.
Benefits of Advanced Oxidation Process? - ANSWER Removed Total Organic Carbons and creates a
barrier for microorganisms.
How much Total Organic Carbon (TOC) and Conductivity can Reverse Osmosis remove? - ANSWER <
0.5mg/l TOC and 250mg/l conductivity.
MF, RO, UV/H2O2 is an example of what? - ANSWER MULTIPLE BARRIER TO PATHOGENS
