Developing a New DSS for SuDS Design and Flood Risk Management
1. Developing a New DSS for SuDS
Design and Flood Risk Management
Jo-fai Chow*, Dragan
Savić, David Fortune
and Zoran Kapelan
2. Introduction
jo-fai.chow@microdrainage.co.ukSlide (01/21)
• About this project
– STREAM Industrial
Doctorate Centre
• Cranfield, Exeter*,
Imperial, Newcastle &
Sheffield University
– Micro Drainage (an XP
Solutions Company)
– EPSRC funded
• Goal
– New features for
commercial drainage design
software
• About me
– Civil and Environmental
Engineering (BEng, MSc)
– Water Infrastructure
Asset Management
Consultant
• Data-driven Modelling
• Optimisation using
Genetic Algorithm
– PhD candidate in
Hydroinformatics
4. Research Objectives
jo-fai.chow@microdrainage.co.ukSlide (03/21)
• Maximising multiple benefits
– Identifying best trade-off
• Communication Platform
– Planners, engineers, architects,
landscape architects, developers, local
government, insurance companies,
water companies …
• Integration with existing
software
– Additional decision support
5. Sustainable Drainage Systems
Conventional Drainage Systems
How to Define a “Good” Drainage Design?
jo-fai.chow@microdrainage.co.ukSlide (04/21)
• In the past
– least cost design with
sufficient hydraulic
performance
• Now
– Market drivers: legislation,
best practice
– must consider the use of
SuDS first
• Challenge
– optimal combination?
Better use
of large
pipes ??
Das Park Hotel, Australia
7. SuDS in Drainage Network Model
jo-fai.chow@microdrainage.co.ukSlide (06/21)
Porous car park
Swale
Pond
A typical development site model
8. How many different options?
jo-fai.chow@microdrainage.co.ukSlide (07/21)
No. of options = No. of feasible SuDS techniques ^ No. of Location
= 51
= 5
Simple calculation example:
Say, after an initial analysis of a
development site, there is ONE suitable
location for SuDS. For this location, there
are FIVE feasible choices of SuDS.
How many different design options?
9. How many more options?
jo-fai.chow@microdrainage.co.ukSlide (08/21)
Second calculation example:
Now consider THREE suitable locations for
SuDS and FIVE feasible choices of SuDS.
How many different design options now?
No. of options = No. of feasible SuDS techniques ^ No. of Location
= 53
= 125
10. Can it get more complicated?
jo-fai.chow@microdrainage.co.ukSlide (09/21)
• Solution
– Brute Force?
– Optimisation
– Smart Rules
– Parallel Computing
• Yes! There are other
factors
– Sizing parameters
– Infiltration
parameters
– Multiple scenarios
• The search space is
HUGE!!
17. Optimisation Objective 2 – Costs
jo-fai.chow@microdrainage.co.ukSlide (16/21)
£0
£100,000
£200,000
£300,000
£400,000
£500,000
£600,000
SuDS1 SuDS2 SuDS3
Cost Summary
CAPEX OPEX (over 50 years) Land Value Whole Life Cost (over 50 years)
CAPEX (Construction Cost)
OPEX (Maintenance Cost over 50 years or 100 years)
Land Value (unit cost x surface area)
Whole Life Cost
18. GANetXL Video Demo
Savić, D.A., Bicik J. and Morley M.S. (2011). GANetXL: A DSS generator for multiobjective optimisation of
spreadsheet-based models, Environmental Modelling & Software, Vol. 26, 551-561.
jo-fai.chow@microdrainage.co.ukSlide (17/21)
19. Exploring the Trade-off
jo-fai.chow@microdrainage.co.ukSlide (18/21)
Least cost solution which
just satisfies the hydraulic
performance requirements
Solution with better
hydraulic performance
but a higher cost
Most relevant for
decision makers
20. Exploring the Trade-off
jo-fai.chow@microdrainage.co.ukSlide (19/21)
0
2
4
6
8
10
12
14
16
18
20
0 50 100 150 200 250 300
Flow(m3/s)
Duration (Minutes)
Flow Rate at Various Stages of SuDS TreatmentTrain
Inflow (Connection1)
Outflow (Connection 1) -> Inflow
(SuDS 1)
Outflow (SuDS1) -> Inflow
(Connection 2)
Outflow (Connection 2) -> Inflow
(SuDS 2)
Outflow (SuDS 2) -> Inflow
(Connection 3)
Outflow (Connection 3) -> Inflow
(SuDS 3)
Final Outflow at Outlet
Peak Flow Constraint
0
5
10
15
20
25
30
0 50 100 150 200 250 300
Volume(m3)
Duration (Minutes)
Storage Requiredat Various Stages of SuDS TreatmentTrain
Storage (Connection 1)
Storage (SuDS 1)
Storage (Connection 2)
Storage (SuDS 2)
Storage (Connection 3)
Storage (SuDS 3)
Storage (TOTAL)
0
5
10
15
20
25
30
35
Total
Nitrogen
Total
Phosphorus
Total
Suspended
Solids
Hydrocarbo
ns
Heavy
Metals
Pollutant Concentration (mg/L)
Concentration
(Inlet)
Concentration
(Regulation
Targets)
Concentration
(Outlet)
£0
£100,000
£200,000
£300,000
£400,000
£500,000
£600,000
SuDS1 SuDS2 SuDS3
Cost Summary
CAPEX OPEX (over 50 years) Land Value Whole Life Cost (over 50 years)
Final Outflow
Total Storage
Final Pollutant Conc.
Costs
0
2
4
6
8
10
12
14
16
18
20
0 50 100 150 200 250 300
Flow(m3/s)
Duration (Minutes)
Flow Rate at Various Stages of SuDS TreatmentTrain
Inflow (Connection1)
Outflow (Connection 1) -> Inflow
(SuDS 1)
Outflow (SuDS1) -> Inflow
(Connection 2)
Outflow (Connection 2) -> Inflow
(SuDS 2)
Outflow (SuDS 2) -> Inflow
(Connection 3)
Outflow (Connection 3) -> Inflow
(SuDS 3)
Final Outflow at Outlet
Peak Flow Constraint
0
5
10
15
20
25
30
0 50 100 150 200 250 300
Volume(m3)
Duration (Minutes)
Storage Requiredat Various Stages of SuDS TreatmentTrain
Storage (Connection 1)
Storage (SuDS 1)
Storage (Connection 2)
Storage (SuDS 2)
Storage (Connection 3)
Storage (SuDS 3)
Storage (TOTAL)
0
5
10
15
20
25
30
35
Total
Nitrogen
Total
Phosphorus
Total
Suspended
Solids
Hydrocarbo
ns
Heavy
Metals
Pollutant Concentration (mg/L)
Concentration
(Inlet)
Concentration
(Regulation
Targets)
Concentration
(Outlet)
£0
£100,000
£200,000
£300,000
£400,000
£500,000
£600,000
SuDS1 SuDS2 SuDS3
Cost Summary
CAPEX OPEX (over 50 years) Land Value Whole Life Cost (over 50 years)
Final Outflow
Total Storage
Final Pollutant Conc.
Costs
0
2
4
6
8
10
12
14
16
18
20
0 50 100 150 200 250 300
Flow(m3/s)
Duration (Minutes)
Flow Rate at Various Stages of SuDS TreatmentTrain
Inflow (Connection1)
Outflow (Connection 1) -> Inflow
(SuDS 1)
Outflow (SuDS1) -> Inflow
(Connection 2)
Outflow (Connection 2) -> Inflow
(SuDS 2)
Outflow (SuDS 2) -> Inflow
(Connection 3)
Outflow (Connection 3) -> Inflow
(SuDS 3)
Final Outflow at Outlet
Peak Flow Constraint
0
5
10
15
20
25
30
0 50 100 150 200 250 300
Volume(m3)
Duration (Minutes)
Storage Requiredat Various Stages of SuDS TreatmentTrain
Storage (Connection 1)
Storage (SuDS 1)
Storage (Connection 2)
Storage (SuDS 2)
Storage (Connection 3)
Storage (SuDS 3)
Storage (TOTAL)
0
5
10
15
20
25
30
35
Total
Nitrogen
Total
Phosphorus
Total
Suspended
Solids
Hydrocarbo
ns
Heavy
Metals
Pollutant Concentration (mg/L)
Concentration
(Inlet)
Concentration
(Regulation
Targets)
Concentration
(Outlet)
£0
£100,000
£200,000
£300,000
£400,000
£500,000
£600,000
SuDS1 SuDS2 SuDS3
Cost Summary
CAPEX OPEX (over 50 years) Land Value Whole Life Cost (over 50 years)
Final Outflow
Total Storage
Final Pollutant Conc.
Costs
Least Cost
Acceptable Performance
Most expensive
Best Performance
22. Summary & Future Works
jo-fai.chow@microdrainage.co.ukSlide (21/21)
• Future Works
– More objectives and
trade-off
• Social Impact
• Potential Flood Risk &
Consequence
• Carbon Cost
– More real data
– More discussion with
practitioners
– Integration with
commercial software
• Summary
– Motivation
• Better decision
support for drainage
design
– Prototype DSS for
SuDS selection
– GANetXL Demo:
• Trade-off between
Hydraulic
Performance and
Whole Life Cost
This is part of my PhD work with University of Exeter and Micro DrainageSuDS in UK, LIDs in US, WSUD in AustraliaMotivation of project, research challenge and a demo of the application
A little bit of my background in this fieldI was a civil engineer by trainingThen I worked …Now I am …My project is sponsored by STREAM IDC – which is ….All the research projects focus on industrial applications – so each of the students has at least one industrial sponsorIn my case – Micro Drainage I must mention the name of XP solution – because it is the mother company of Micro Drainage, Micro Drainage is better known in UK and Middle East, elsewhere it is always XP solutionsThe project is funded by Research Council The ultimate goal is to …
OK let’s talk about motivation of the projectSustainability – it also applies to many of your projectsAchieve the optimal trade-off between cost, environmental impact and social impactWe have looked at what is already available in some common software packages, both commercial and open sourceWe found there is not enough emphasis on social impact, for example, amenity value, added value to the communityPartly because it is fupyhyhy
Better software for drainage designEach stakeholder has his/her own preferences of “good” designConflicting interestsNew software features for existing drainage software packages – WinDes and XP SWMMBetter tool for drainage design
Some get infiltrated, some get evapotranspirated, some get conveyed,The main point is source management, deal with the water at source, reduce volume of runoff to downstream receiving water bodiesThere is more, some SuDS can provide water treatment, bring additional value and benefits to the whole systems
So what is it like in a typical drainage network model?Here is an example of a typical development site design in Micro Drainage’s software WinDesThere are some SuDS used in this design, some very common techniques used todayPorous car park, swale, pond. Of course there are more techniques available for modelling but I am only showing those in this example So we can include these SuDS as model components and run simulations to analysis their hydraulic performance, impact on flooding etcWhat if we want to try different combination of SuDs, different order, different techinques??