Significance of rainwater and reclaimed water for sustainable urban water … · 2013-12-11 · Chlorination Reclaimed water 2）Analysis of BOM by FTMS ・Molecular level composition

Significance of rainwater and reclaimed water for

sustainable urban water use

Hiroaki FURUMAIProfessor, Research Center for Water Environment TechnologyUniversity of Tokyo

1

JST-NSREC Workshop on Sustainable Water Use, Tokyo, 21-22 Oct. 2013

Outline Introduction- Water resource and use in Tokyo- Concern about the sustainability of urban water use

Research on rainwater and reclaimed water use- Evaluation of water safety considering virus contamination- Evaluation of water quality stability by microbial regrowth- Energy consumption of water reclamation and supply

Summary

2JST-NSREC Workshop on Sustainable Water Use, Tokyo, 21-22 Oct. 2013


Water resource and water supply in Tokyo

80%

20%

<1%

Tone-Ara river system

Tama river system

Sagami river system


Wastewater Treatment Plant

Surface water dependentDam storage typeOne-through water use

Conventional Water Resource Developmentand Urban Water Use in Japan

Drinking watertreatment plant

Escalated water demandGroundwater abstractionGround subsidenceShift to Surface water Dam constructionEutrophication problems

5

WWTP

Watershed-based Sustainable Urban Water Use

DWTP

Enhanced Infiltration

Water Recycling SocietyRainwater

Use

Reclaimed Water Use

Groundwater Recharge and Use

Development of self-owned water resources in urban area

Conservation of Water Environment



Concern about safe and stable urban water use Climate change would accelerate localization of available

water resources and consequently it would become more difficult to keep stable water supply.

To assure the safe and stable urban water supply, we must reexamine the availability of “rainwater”, “groundwater”, and “reclaimed water” as well as surface water.

It is necessary to develop novel evaluation approaches for risk and stability of water quality and devise methods for designing water use, considering environmental cost evaluation and preferences of various water users.

Well-balanced urban water use systems should be established considering climate change in the future.


Various Water Resource in Urban Area

Rainwater

Ground water Reclaimed

water

Dam water

Water Quality Information

Multiple Urban Water Use

River water

Evaluation of water safety considering virus contamination

Evaluation of water quality stability by microbial regrwoth

Microbial Source Tracking

WQ evaluation of water resources in urban area

Water Quality Transformation Potential

Health Risk Management

Treatment Performance Evaluation


Viral sample

Dose with EMA

Light exposure

RNA Extraction RT-PCR

Completed-capsid virus

Damaged-capsid virus Naked RNA EMA molecule

EMA treatment can exclude detection of RNA from damaged virusEMA treatment

Can beamplified by PCR

Cannot be amplified by PCR

Application of Ethidium Monoazide coupled with quantitative PCR method (EMA-PCR)

-6

-5

-4

-3

-2

-1

00 5 10 15

Log(

N/N

o)

time (min)


-6

-5

-4

-3

-2

-1

00 5 10 15

Log(

N/N

o)

time ( min)Cl2 1 mg/l (N = 4)

Open symbol: Not detected (below detection limit)Plaque assay EMA-PCR PCR

EMA-PCR was able to reflect the integrity and damage of virus capsid

Cl2 0.25 mg/l (N = 4)

Inactivation test of poliovirus by chlorination

PCR

EMA-PCR

Plaque assay

PCR

EMA-PCRPlaque assay


Evaluation of water quality stability

Removal and formation of biodegradable organic matter (BOM)

・AOC (Assimilable Organic Carbon)・BGF(Bacterial Growth Fingerprint)

１） Determination of BOM

Res

idua

l chl

orin

eAOC conc.

No-growth zone

Growth zone

Chlorination

Reclaimed water

２） Analysis of BOM by FTMS・Molecular level composition

→ Water quality stability can be evaluated by microbial regrowth

High potential of microbial regrowth

Evaluation of various water resources

Surface water

Secondary effluent

Water intake

Groundwater

Reclaimed water

RainwaterCoagulation, Filtration, Ozonation etc.


• High AOC in ozonated water

• Remarkable AOC formation by ozonation

0

100

200

300

400

500

600 A

OC

(μg-

C/L

)AOC-2nd effluentAOC-Reclaimed water

Process A B C D1 D2 E1 F1 F2Coagulation

Sand filtration Biofiltration Ozonation Microfiltration Reverse osmosis

Activated carbon Ultraviolet Post chlorination

• Increased AOC by UV radiation treatment

• Low AOC after reverse osmosis (RO) membrane treatment

Change of AOC during reclamation process


10

100

1000

10000

100000

1000000 106

105

104

103

102HPC

(CFU

/mL)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

Total

chlo

rine (

mg/

L)

November January April June August

0

100

200

300

400

500

600

AO

C(µ

g C

/L)

0

100

200

300

400

500

600

AOC

(µg

C/L)

HPC

Residual chlorine

AOC decrease(Nov. Apr. June)

Regrowth was observed under depleted Cl2, while AOC was decreased

Water quality change in distribution system

AOC no-change(Jan. Aug.)

Regrowth

No-regrowth

High Cl2

Depleted Cl2


Gutter

Curb

Sidewalk (Water-retentive Interlocking)Capillary Pillar

Filling Concrete

●

●●●●

: thermocouple sensor2000

Partition Plate

Infiltration Trench

3000 300

1@1000+500=1500

550

450

Storage Tank with supporting platforms and impermeable sheets

Crushed Stone

200

Overflow

Inlet

Water Transmission Sheet

Newly Developed Rainwater Harvesting Facilities in Road for Control of Flood and Heat Island PhenomenonPavement of Rainwater Cyclical System (PRaCS)

Ｄｅｔａｉｌ of Experimental Facilities

Asphalt

PRaCS

Length14m

Catchment Area 112m2

Storage Capacity 2.38m3

13

Cross-section


Reducing effect of road surface temperature


Water Temperature

EC

Water DepthDO

Turbidity

pH

Water quality change in stored road runoff(July to Sep. in 2012)

100 %

100 %

77 %

Treated ground water

Rain waterTap water

Untreated ground water

28 %Reclaimed wastewater

1.20gCO2/L

77 %0.18gCO2/L

0.50gCO2/L

0.14gCO2/L

0.34gCO2/Ｌ

Community

Comparison of CO2 emission for different water resources

Information on total energy consumption should be further considered to compare applicability of different water resources.

Consideration of environmental load by water production and supply

Case of Tokyo

Water use coverage

Water use coverage

Water use coverage

Water use coverage

Water use coverage


Summary Rainwater and reclaimed water have been applied to meet the

increased water demand in urban area. From the viewpoint of sustainable water use, they have been recognized as precious urban self-owned water resources. They can be applied for multiple purposes of miscellaneous water use.

In order to promote the rainwater (roof and road runoff) use, water quality should be managed to secure the safety and aesthetic appearance. Therefore, we have to pay attention to possible contamination in rainwater and proper control of water reclamation if necessary. For the purpose, WQ standard and WQ control method ology should be established based on available treatment and operational technology.

As well as WQ, we also have to consider the necessary energy consumption to produce and supply the alternative water, comparing with current water supply system. In this aspect, rainwater and runoff water is very prospecting, although amount variability is expected very high in the future.

17


http://www.recwet.t.u-tokyo.ac.jp/crest2009/english/index.html

19

Thank for your attention


WWTP

DWTP

Enhanced Infiltration

Water Recycling

SocietyRainwater Use

Reclaimed Water Use

Groundwater Recharge and Use

Development of self-owned water resources in urban area

Conservation of Water Environment

Watershed-based Sustainable Urban Water Use

Hiroaki FURUMAI [email protected]

Documents

Significance of rainwater and reclaimed water for sustainable urban water … · 2013-12-11 · Chlorination Reclaimed water 2）Analysis of BOM by FTMS ・Molecular level composition