DT117/4 Sustainable Build & Design - Class Presentations

1. Name: Thomas Geoghegan
Student No: D06112565
Module: Sustainable Design
Lecturer: Sonya Daly
Submission: Presentation report & Presentation
Project Site: Sea View Bungalow, Lurgacloy, Clogher Ballina, Co
Mayo.

2. Table of Contents Page No
1. Background on Sustainable Drainage Systems (SUDS)...........................................2
2. Selecting the best SUDS
option...................................................................................3
3. Above ground attenuation
options..............................................................................4
3.1 Basins & Ponds...........................................................................................................4
3.1.1 What are
they......................................................................................................4
3.1.2 How they
work...................................................................................................4
3.1.3 Quantity..............................................................................................................
5
3.1.4 Quality................................................................................................................
5
3.1.5 Amenity..............................................................................................................
5
3.2 Filters & Swales..........................................................................................................6
3.2.1 What are
they......................................................................................................6
3.2.2 How they
work...................................................................................................6
3.2.3 Quantity..............................................................................................................
6
2

3. 3.2.4 Quality................................................................................................................
7
3.2.5 Amenity..............................................................................................................
7
4. Case
Study.....................................................................................................................8
4.1 Marlborough
School...................................................................................................8
4.1.1 What are
they......................................................................................................8
4.1.2 How it
works......................................................................................................8
4.1.3 Benefits..............................................................................................................
.9
5. Why choose above ground attenuation
systems?....................................................10
6. Appendix
Presentation...............................................................................................11
1. Background on Sustainable Drainage Systems
Drainage design in the past has been simply using a rational method size pipes to ensure
water is removed as quickly as possible to ensure flooding of other areas and pollution wash
off into a natural environment.
A Best Management Practice is commonly used throughout the world. This is not used in the
UK and Ireland, possibly because the word drainage is not included. It is referred to as
Sustainable Drainage Systems (SUDS). SUDS can be quoted as offering a “total solution to
3

4. rainwater management while traditional drainage can be considered as only providing a
“collection and disposal”
Suds also apply in rural developments. Over 80% of our rivers are below ground status.
Most pollution comes from:
- Underperforming small treatment plants
- Overloaded communal septic tanks
- Clusters of single unit septic tanks
- Farmyard runoff
Over the past decade Irelands parks have been developing a more sustainable approach
with integrated constructed wetlands. This holistic approach has been successful with
dealing with farmyard runoff, industrial waste, sewage as well as urban pollution.
2. Selecting the best SUDS options
When selecting SUDS it is important to consider quality, quantity and amenity equally. Too
many occasions has quantity been of the highest priority. The diagram below shows the old
thinking of conventional approach and is now thinking of designing for flooding to balance
each element.
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5. Figure 1.1: Diagram of conventional vs integrated
There is no correct way in choosing the best suds, so several options may meet the criteria
and have to be judged accordingly.
Selecting and design suds are multi disciplinary processes. There influenced by factors like
planning, water resource, architectural and landscape requirements. Once an assessment of
the site drainage technique is done it can be selected.
The selection wool is based on the surface water management train and is designed to lead
the designers through selection process in:
- Design techniques to meet design criteria
- Drainage techniques at the top of the management train are preferred to those
further downstream
- There is no single correct solution and must look at external factors
- The drainage system is in accordance with drainage systems
Don’t approach the selection process as purely technical. Decide to put it as a wider context.
For example ponds; very great environmental enhancer and increases property values a lot
but overall may be overridden by other considerations.
3. Above ground attenuation options
3.1 Basins and Bonds
5

6. 3.1.1 How they work
Basins are areas for storage of surface runoff are free from water under dry weather flow
conditions. These include
- Flood plains
- Detention basins
- Extended detention basins
Ponds contain water in dry weather and are designed to hold more when it rains. They
include:
- Balancing and attenuation ponds
- Flood storage reservoirs
- Lagoons
- Retention Ponds
- Wetlands
Basins and ponds tend to be found at the end of surface water management trains. They
can be used to source control and can be implanted if extended treatment of runoff is
required for wildlife or landscape reasons
3.1.2 How they work
Basins and ponds store water at the ground surface as:
- Temporary flooding
- Flood plains
- Permanent ponds
6

7. Figure 1.2: How Basins and ponds work
These are designed to manage under quantity and quality
3.1.3 Quantity
They store floodwater and release it slowly once the risk of flooding is over
3.1.4 Quality
Basins and ponds Treat run off by:
- Settlement of solids in still water
- Conditions and promotes settlement
- Adsorption by vegetation of soil
3.1.5 Amenity
The opportunities basins and ponds offer are:
- Sports and recreation
- Wet ponds are great to store water for reuse
- Be part of public open space
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8. 3.2 Filter strips and swales
3.2.1 What are they?
Filter strips and swales are vegetated that rain water evenly off impermeable areas. Swales
are long shallow channels whilst filter strips are gently sloping areas of ground.
Figure 1.2: How Filter strips & swales work
3.2.2 How they work
They work by mimicking natural drainage patterns by allowing rainwater through
vegetation, slowing and filtering the flow. Swales are also designed for:
- Infiltration
- Detention
8

9. - Treatment of runoff
3.2.3 Quantity
Swales are designed for:
- Conveyance systems
- Check dams to increase attenuations
- Infiltrations
Filters trips are designed for:
- Attenuation Flow
- Reduce drain impermeable areas
3.3.4 Quality
Swales and filters remove polluting in the solids through filtration and sedimentation.
3.3.5 Amenity
Swales and filters trips are often interpreted into surrounding land use
Examples are:
- Public open space
- Road verges
Grass and flowers can be planted for wildlife after the swales are in
9

10. 4. Case Study
4.1 Marlborough School
Location: Redeltorn, Worcestershire England
Description:
A school development which originally was designed with conventional drainage that
flowed to a pump station from where it was pumped to a school.
During construction it became clear that one playground area could not be drained by
gravity to the pumping station
Main suds used:
- Swales
- Detention Basins
4.1.1 How it works
The suds scheme implemented following the contour of the site and drains downhill to
an ipsley stream (Removing the annual charge from the sewer construction).
10

11. Swales collect overland flows from:
- Adjacent site
- Runoff from car park
- Playgrounds
Hence providing source of control
The retention basins drain the main driveway that is connected to a constructed wetland
(pond) which also takes runoff from the roof.
4.1.2 Benefits
The suds system has brought a valuable amenity and teaching resource for the school
11

12. 5. Why choose above ground attenuation systems?
- Installed and maintained at a lower cost compared to more traditional systems of
drainage
- Problems can be observed and dealt with as they arise(swales)
- Can be incorporated into any terrain
12

13. 6. Appendix
6.1 Presentation
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