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
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
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%
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
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
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