Introduction

Question 1

How does linear living affect the water sector?

Answer 1

o Energy linearity leading to climate change with droughts and floods as consequences
o Linearity in use of nutrients which causes eutrophication
o Use of material like plastic – choking up our waters.

Question 2

Describe the connection of planetary boundaries and the water sector?

Answer 2

the concept of Planetary boundaries – it tries to define the safe operating space for humanity, and according to these researchers we are way out of bounds when it comes to N and P flows, with biodiversity. Several of these boundaries concern our sector – freshwater use, the N and P flows, novel entities and climate change…

Question 3

How much of P and N in the Baltic Sea comes from WWTP?

Answer 3

o 33% of nitrogen and 16% of phosphorus to Baltic Sea comes from wastewater treatment plants

Question 4

What are some challenges to implement source-separating systems in the water sector?

Answer 4

o Costs
o Pollutants
o Habits
o Existing technologies
o Infrastructure
o Political
o Investments
o Public interest

Question 5

• What is the volume, main resource and main problem of blackwater?

Answer 5

o 6 – 30 L, nutrients, pathogens

Question 6

• What is the volume, main resource and main problem of greywater?

Answer 6

o 100 – 120 L, heat & water, micropollutants

Question 7

• Pros with source-separating systems

Answer 7

o Resource recovery
o Locally produced fertilizer
o Less eutrophication
o Less water use
o Increased circularity

Question 8

• Cons with source-separating systems

Answer 8

o Increased costs
o Complicated and complex technologies
o Approval needed for new technologies
o Regulations for reuse of fertilizers
o Scale problem – difficult in bigger cities
o Existing infrastructure

Question 9

• Drivers for source-separating systems

Answer 9

o Water savings
o Increased potential for biogas extraction
o Increased potential for nutrient and water recycling
o Decreased eutrophication
o Delay/avoiding rebuilding WWTP due to it hitting capacity
o Increased potential of heat recovery on building/area level
o Reduced release of laughing gas
o Better control on emerging pollutants
o Innovation
o Reduced release of pathogens
o Extension of service delivery
o Compost production
o Young generation demands sustainability

Question 10

• Risks

Answer 10

o Increased costs
o Misuse of system by users
o Emerging pollutants – novel entities
o The yuck factor
o Possibility of low demand on recovered resources
o Cities are not organized for resource recovery
o Increased demand on cooperation within and outside jurisdiction
o Not fully mature technologies
o Few technology providers compared to the conventional system
o Need of technological and institutional innovation

Question 11

• How do we make source-separating systems happen?

Answer 11

o Cooperation between water utility, waste utility and energy utility

Question 12

• Existing examples of source-separating systems

Answer 12

o Hamburg
o Helsingborg
o Sneek
o Durban
o Port-Au-Prince & Cap Haitien
o El Alto