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.

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

1

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

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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.

3

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

4

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

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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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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

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- 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

8

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).

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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

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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

11

6. Appendix

6.1 Presentation

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