Integrated Urban Water Management

•Sybil Sharvelle •Larry Roesner

The CSU Urban Water Center

I – Toward Holistic Management of Urban Water Systems

Making better use of our urban water resources through “the use of effective and innovative approaches and technologies,

a commitment to long-term stewardship of our water infrastructure, and collaboration with all key stakeholders” (USEPA, 2007, Sustainable

Water Infrastructure Initiative)

The Urban Water Infrastructure System

Treatment plant

Treatment plant

Disposal

Supply

Distribution system

Collection system Drainage

system

The Pre-Urban Water Balance

Undeveloped

RAIN

RUNOFF INFILTRATION 10 % 50 %

40% Evapotranspiration

Effect of Urban Development

Developed

RAIN

RUNOFF INFILTRATION

POTABLE WATER

SSOs/CSOs WWTP

30 % 25 %

35% Evapotranspiration

The Water Supply Infrastructure System

Treatment plant

Treatment plant

Disposal

Supply

Distribution system

Collection system Drainage

system

The Wastewater Infrastructure System

Treatment plant

Treatment plant

Disposal

Supply

Distribution system

Collection system Drainage

system

The Urban Runoff Infrastructure System

Treatment plant

Treatment plant

Disposal

Supply

Distribution system

Collection system Drainage

system

Issues

• Aging water supply infrastructure – Water loss in water supply systems – Water quality at the tap – System security

• Aging sewer and drainage system infrastructure – CSOs, SSOs, BMP malfunction

• Enormous cost of rehabilitation • Energy to run these systems • Mindset of water agencies

9

But who’s thinking about the “water system” ??

• Most municipalities have independent departments for water, wastewater, and stormwater

• For some, collection/distribution systems is a separate department

• Integrated management is difficult

17-10

Toward a Better Solution

11

Water Supply Alternatives

• Is bottled water the answer? • How about point of use treatment? • Rainwater harvesting with POU treatment?

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Point of Use Treatment

17-12

Reuse

How about Reuse?

Treatment plant

Treatment plant

Disposal

Supply

Distribution system

Collection system Drainage

system

Reuse saves water and $

17-13

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Reuse of WWTP

Effluent is Simplest

+ Limited Institutional Issues - Must pump back up hill - No SSO, CSO relief - Do we need secondary treatment for reuse?

17-14

Household Graywater

Reuse is Attractive

+ Reduces potable water demands + Reduces wastewater loads - Requires homeowner maintenance - Public Health Departments don’t like it

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

17-15

Reuse of Excess

Runoff is Possible

+ Reduces potable water demands + Reduces geomorphic effects in receiving streams - Requires storage and distribution system

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

Treatmentplant

Treatmentplant

Disposal

Supply

Distribution

CollectionDrainage

16

City of Fort Collins energy expenditures

Operations Services, 37.6%

Parks, 8.8%

Poudre Fire Authority, 3.5%Traffic, 2.3%

Utilities Water Production,

12.9%

Utilities Water Reclamation & Biosolids Div,

23.4%

Library District, 3.2%

Utility Finance & Budget, 3.2%

Others, 5%

Source: City of Fort Collins Open Book Project

2009 Data

36%

City greenhouse gas emissions

Source: Fort Collins Climate Action Plan 2009 Status Report

Integrated Urban Water Management Concepts

19

MUNICIPAL WASTE WTR

SYSTEM

MUNICIPAL STORM WTR SYSTEM

P T B G MUNICIPAL

WTR SUPPLY SYSTEM

- Finished Water - Fire Demand

Irrigation

Receiving Waters

I. Conventional Urban Water System

20

MUNICIPAL WASTE WTR

SYSTEM

MUNICIPAL STORM WTR SYSTEM

MUNICIPAL WTR SUPPLY

SYSTEM

-

Raw Water

Fire Demand

Irrigation

Point of Use/Entry Treatment

Receiving Waters

P T B G

II. Point of Use/Entry System

21

Neighborhood/Community Waste Wtr

System

- Collection - Treatment

MUNICIPAL WASTE WTR

SYSTEM

MUNICIPAL STORM WTR SYSTEM

MUNICIPAL WTR SUPPLY

SYSTEM

- Raw Water - Fire Demand

Irrigation

Neighborhood/Community Wtr System

- Finished Water

X

Receiving Waters

P T B G

III. Neighborhood/Community Water & Wastewater Treatment

23

IV. Household Graywater Reuse

24

MUNICIPAL WASTE WTR

SYSTEM

Neighborhood/Community Waste Wtr

System

- Collection - Treatment

MUNICIPAL STORM WTR SYSTEM

MUNICIPAL WTR SUPPLY

SYSTEM

- Raw Water - Fire Demand

Irrigation

Neighborhood/Community Wtr System

- Finished Water

X

Receiving Waters

P T B G

V. Completely Integrated-Decentralized Urban Water System

25

Neighborhood/Community Waste Wtr

System

- Collection - Treatment

MUNICIPAL WASTE WTR

SYSTEM

MUNICIPAL STORM WTR SYSTEM

MUNICIPAL WTR SUPPLY

SYSTEM

- Raw Water - Fire Demand

Irrigation

Neighborhood/Community Wtr System

- Finished Water

X

Receiving Waters

P T B G

Storage

MUNICIPAL WASTE WTR

SYSTEM

Neighborhood/Community Waste Wtr

System

- Collection - Treatment

MUNICIPAL STORM WTR SYSTEM

MUNICIPAL WTR SUPPLY

SYSTEM

- Raw Water - Fire Demand

Irrigation

Neighborhood/Community Wtr System

- Finished Water

X

Receiving Waters

P T B G

Water Balance Model – City of Fort Collins

220 Gallon Rain Barrel Storage

Water Balance Model – Fort Collins

Graywater Reuse

Influent

overflow

Household Scale Neighborhood Scale

Current Wastewater Management

WWTP

Energy & $$$

N & P

Graywater Blackwater

Graywater Separation

Graywater Blackwater

Anaerobic Digester

Green Energy

Compost

High N Low Pathogen

Anaerobic Digestion

High Carbon Waste

Organics Acids

Acids CH4

High Nutrient Low Odor

Waste

Anaerobic Environment

Cogeneration

Hot Water

CH4

Green Power

Near Complete Pathogen Removoal

Neighborhood System

Anaerobic Digester Blackwater

Natural Gas Biogas

Curbside Pickup of Yard Waste

Anaerobic Digester Blackwater

Summary

• Aging Infrastructure – Opportunity to do things differently

• Decentralized water and wastewater management can be considered

• Graywater reuse offers notable water and wastewater savings – Can be combined with anaerobic digestion of

blackwater

Thank You