investigating the role of drought and water conservation ... · in california, water conservation...

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In California, water conservation becoming more important as a means to reduce water scarcity (especially during latest drought). First time in history State mandated conservation. Measures were often undertaken without a proper knowledge of positive and negative outcomes of conserving water State and local agencies also engaging in more wastewater reuse, yet do not seem to recognize relationship between certain types of conservation (e.g., indoor residential conservation) and reuse of treated municipal wastewater Questions addressed: How did the drought and water conservation measures impact wastewater agencies and wastewater reuse? What are the effects on recycled water reuse of any changes in the quality of treated municipal wastewater? This study will help support policy and follow-up actions concerning water conservation measures. Motivation Current Findings and Status i. Data on monthly influent flow and effluent TDS (2013-present) (CIWQS and individual WWTPs). ii. Monthly Conservation mandate and achieved data (2013- present) (SWRCB). iii. Wastewater treatment plants regional location, plant design flow, treatment technology, recycled water usage, source data are collected. Lower Flows Causing Higher Salinity Problem Future Scope Performing an econometric analysis relating conservation measures with flow rates and salinity to investigate the impact of drought and water conservation on reuse of treated municipal wastewater. Acknowledgement Thanks to my Supervisor Dr. Kurt Schwabe for continuous support and for given me opportunity to work and gain valuable experience while working on this project. Also thanks to Quynh Tran and Dr. David Jassby for providing support during the project. Contact info: ramin004 @ucr.edu (email), [email protected] (Supervisor), qtran009@ucr. edu (co-author), [email protected] (Co-author) Investigating the Role of Drought and Water Conservation Efforts on the Reuse of Treated Municipal Wastewater Graphical Abstract i. The selection criteria are established to determine the relationship between residential water conservation and wastewater quality. ii. NPDES permit holding wastewater agencies (authorized by Clean Water Act) are selected mostly; some WDR holders. iii. Agencies from different hydrologic regions are selected. Different Phases of the Project Study wastewater agencies background and source. Contact with wastewater agencies from Southern California to obtain influent and effluent quantity and quality data. Cleaning data collected from California Integrated Water Quality System Data collection from rest of California Monthly conservation data Statistical model development Determine the relationship between influent flow and effluent TDS of WWTPs in California Publications and outreach Data Collection Selection Criteria Industrial Reuse Irrigation Water Treatment Plants Indoor Water Conservation Domestic Wastewater Treatment Plants Groundwater Recharge Creek Discharge 2014 2015 2016 2014 2015 2016 Refat Amin, Kurt A. Schwabe, Quynh K. Tran and David Jassby -0.2 -0.1 0 0.1 0.2 0.3 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 South Coast Region (Tapia WWRF) Mandated Period Percent change in influent Percent Change in TDS conc -15 -10 -5 0 5 10 15 20 -13 -11 -9 -7 -5 -3 -1 Colorado River (Coachella Valley Water District) Mandated Period Percent change in influent Percent change in TDS conc -20 -10 0 10 20 30 40 50 0 10 20 30 40 50 60 South Coast Region (Simi Valley WWTP) Mandated Period %change in influent flow %change in TDS concentration How Does Drought Impact Wastewater? Indoor conservation -Wastewater quality - Demand - Available wastewater to reuse Agencies faced Operational and financial challenges. Pollution (e.g. salinity) challenges. These challenges make it harder for agencies to meet their water quality standards (Title 22, chapter 3) and/or demands for recycled water. Reference 2014 2015 2016 Fig: IEUA – RP1 inflows vs. wastewater produced per capita in the IEUA – RP1 service area in 2011-2015 (Tran et al.2017) Fig: TDS concentrations in 2010-2015. (Tran et al. 2017) Regression Analysis Y1 it = α i + λ t 1 X1 it + β 2 X2 it + β 3 X3 it + Ɛ it Here, Y1= Influent Flow Y2= Effluent Salinity (TDS concentration) Y2 it = α i + λ t + β 1 X1 it + β 2 X2 it + β 3 X3 it + Ɛ it Equations X1= Conservation Mandate X2= Plant Treatment Technology X3= Plant Design Flow i= regional location t= time Current Status: Cleaning data from CIWQS Data collection from WWTPs Current findings: Lower flows arising from drought and conservation measures (e.g. Data collected from Simi Valley WWTP (2013-2016) shows significant drops in flows - 10.5% during the period of drought). Increase in the concentration of the constituents (salt, nutrients etc.) of the recycled water (e.g. Data from Simi Valley WWTP shows the average TDS conc. in the treated wastewater increased from 662 mg/L to 825 mg/L (Jun,2013-Jun,2016), a 24.6% increase. Tran, Q.K., Jassby, D. and Schwabe, K.A., 2017. The implications of drought and water conservation on the reuse of municipal wastewater: Recognizing impacts and identifying mitigation possibilities. Water Research, 124, pp.472-481.

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Page 1: Investigating the Role of Drought and Water Conservation ... · In California, water conservation becoming more important as a means to reduce water scarcity (especially during latest

In California, water conservation becoming more important as a

means to reduce water scarcity (especially during latest drought).

First time in history State mandated conservation.

Measures were often undertaken without a proper knowledge of

positive and negative outcomes of conserving water

State and local agencies also engaging in more

wastewater reuse, yet do not seem to recognize

relationship between certain types of conservation

(e.g., indoor residential conservation) and reuse of

treated municipal wastewater

Questions addressed:

How did the drought and water conservation measures

impact wastewater agencies and wastewater reuse?

What are the effects on recycled water reuse of any

changes in the quality of treated municipal wastewater?

This study will help support policy and follow-up actions concerning

water conservation measures.

Motivation Current Findings and Status

i. Data on monthly influent

flow and effluent TDS

(2013-present) (CIWQS and

individual WWTPs).

ii. Monthly Conservation

mandate and achieved data

(2013- present) (SWRCB).

iii. Wastewater treatment

plants regional location,

plant design flow, treatment

technology, recycled water

usage, source data are

collected.

Lower Flows Causing Higher Salinity Problem

Future Scope

Performing an econometric analysis relating conservation measures with

flow rates and salinity to investigate the impact of drought and water

conservation on reuse of treated municipal wastewater.

Acknowledgement

Thanks to my Supervisor Dr. Kurt Schwabe for continuous support and for given me

opportunity to work and gain valuable experience while working on this project.

Also thanks to Quynh Tran and Dr. David Jassby for providing support during the

project.

Contact info:

[email protected] (email),

[email protected] (Supervisor),

[email protected] (co-author),

[email protected] (Co-author)

Investigating the Role of Drought and Water Conservation

Efforts on the Reuse of Treated Municipal Wastewater

Graphical Abstract

i. The selection criteria are

established to determine

the relationship between

residential water

conservation and

wastewater quality.

ii. NPDES permit holding

wastewater agencies

(authorized by Clean Water

Act) are selected mostly;

some WDR holders.

iii. Agencies from different

hydrologic regions are

selected.

Different Phases of the Project

Study wastewater

agencies

background and

source.

Contact with

wastewater

agencies from

Southern

California to

obtain influent

and effluent

quantity and

quality data.

Cleaning data

collected from

California

Integrated Water

Quality System

Data collection

from rest of

California

Monthly

conservation

data

Statistical

model

development

Determine the

relationship

between

influent flow

and effluent

TDS of WWTPs

in California

Publications

and outreach

Data Collection Selection Criteria

Industrial

Reuse

Irrigation

Water

Treatment

Plants

Indoor Water Conservation

Domestic

Wastewater

Treatment Plants

Groundwater

Recharge

Creek

Discharge

2014 2015 2016

2014 2015 2016

Refat Amin, Kurt A. Schwabe, Quynh K. Tran and David Jassby

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

South Coast Region (Tapia WWRF)Mandated Period

Percent change in influent

Percent Change in TDS conc

-15

-10

-5

0

5

10

15

20

-13

-11

-9

-7

-5

-3

-1

Colorado River (Coachella Valley Water District) Mandated Period

Percent change in influent

Percent change in TDS conc

-20

-10

0

10

20

30

40

50

0

10

20

30

40

50

60

South Coast Region (Simi Valley WWTP)

Mandated Period

%change in influent flow

%change in TDS concentration

How Does Drought Impact Wastewater?

Indoor conservation -Wastewater quality - Demand - Available

wastewater to reuse

Agencies faced

Operational and financial challenges.

Pollution (e.g. salinity) challenges.

These challenges make it harder for agencies to meet their water

quality standards (Title 22, chapter 3) and/or demands for recycled

water.

Reference

2014 2015 2016

Fig: IEUA – RP1 inflows vs. wastewater

produced per capita in the IEUA – RP1

service area in 2011-2015 (Tran et al.2017)

Fig: TDS concentrations in 2010-2015. (Tran et

al. 2017)

Regression Analysis

Y1it= αi + λt +β1X1it + β2X2it + β3X3it + Ɛit

Here,

Y1= Influent Flow

Y2= Effluent Salinity (TDS concentration)

Y2it = αi + λt + β1X1it + β2X2it + β3X3it + Ɛit

Equations

X1= Conservation Mandate

X2= Plant Treatment Technology

X3= Plant Design Flow

i= regional location

t= time

Current Status:❖ Cleaning data from CIWQS

❖ Data collection from WWTPs

Current findings:❖ Lower flows arising from drought and

conservation measures (e.g. Data collected

from Simi Valley WWTP (2013-2016) shows

significant drops in flows - 10.5% during the

period of drought).

❖ Increase in the concentration of the

constituents (salt, nutrients etc.) of the

recycled water (e.g. Data from Simi Valley

WWTP shows the average TDS conc. in the

treated wastewater increased from 662 mg/L

to 825 mg/L (Jun,2013-Jun,2016), a 24.6%

increase.

Tran, Q.K., Jassby, D. and Schwabe, K.A., 2017. The implications of drought

and water conservation on the reuse of municipal wastewater: Recognizing

impacts and identifying mitigation possibilities. Water Research, 124,

pp.472-481.