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Sustainable Development
Sustainable Water Supply
Alan Shelley May 2000
Flooding in Cheltenham
1 Coleridge, The Ancient Mariner
PREFACE
Water, water everywhere Nor any drop to drink!1
When flooding occurs, the suggestion of rationed water in Britain is
beyond comprehension. Shortages of water in Asia are taken for
granted. With ever increasing demands for water it is recognised that
global reductions are critical to sustainability of the eco-system.
In Britain we have been mindlessly squandering high quality
processed drinking water. The costs of so doing are expensive both
financially and to the environment. It is time to take immediate action
to reduce and regulate demands. WATER IS VALUABLE.
'We can make a difference' -This small project considers methods
that can be employed from the level of an individual, house or
business unit up the scale to the recommendation of regulations
imposed at national levels. As potential designers of landscapes we
are in a position that can influence 'sustainable' practices at each level.
Contents
Page
The Commodity of Water ........................................................................................... 1
Sustainable Water Supply ........................................................................................ 2
Total Water Management. .......................................................................................... 3
Water Cycling and Design Patterns ........................................................................... 4
Protecting Water Catchment Areas............................................................................ 5
Rainwater Harvesting................................................................................................ 6
Recycling and the Treatment of Sewage ................................................................... 9
Reedbed Cleansing ................................................................................................... 1 O
On-plot Case Study .................................................................................................. 11
The Local Watershed ................................................................................................. 16
Waste Management. .................................................................................................. 20
Facilities at Plot/Unit and Neighbourhood Levels ....................................................... 21
Regulation at Local and Watershed Levels ............................................................... 27
Management at Town or Locality Scale ..................................................................... 29
Sustainable Urban Drainage Systems (SUDS) ........................................................ 30
APPENDICES
1. The Environment. ........................................................................................... 34
2. River Che It Flood Alleviation .......................................................................... 39
3. Waterless Toilet System ................................................................................ 40
4. Presentations (Brief talks) .............................................................................. 41
Illustrations
Figure Page
1. The 'hydrological cycle'.................................................................................. 2
2. Water catchment areas ................................................................................... 5
3. Wff filter collector ............................................................................................. 7
4. Rainwater harvesting system ........................................................................ 8
5. Eco-Cabins sewage treatment system ......................................................... 1 O
6. Reedbed 'greywater' treatment.. .................................................................... 10
7. Case Study; location photograph .................................................................. 11
8. Watershed/Catchment Area (map) ................................................................ 12
9. Location within the Watershed (map) ............................................................ 13
10. Average Annual Rainfall ................................................................................. 17
11. Hydrogeological Map ..................................................................................... 18
12. Groundwater Vulnerability Map ..................................................................... 19
13. Unit (house) Level (plan) ............................................................................... 24
14. Plot Level (plan) ............................................................................................. 25
15. Neighbourhood Level (plan) .......................................................................... 26
16. 'What If'? Cambray Place (plan) ................................................................... 32
17. Reedbed Cleansing (photograph) ................................................................. 33
18. Reedbed Cleansing (photograph) ................................................................. 33
19. 'Cotuit' Dry Toilet System (diagram) .............................................................. 40
20. Waterless toilet (photograph) ........................................................................ 40
TABLES
1. Water consumption of household ................................................................... 22
2. Water consumption comparisons ................................................................... 22
3. Domestic hot-water demand ........................................................................... 23
The Commodity of Water
Drinking water is expensive to provide and is prone to shortages in
times of drought. The consumption of clean water is rapidly rising.
The costs of waste management adds to a problem that can be
considerably reduced. Each of us use an average of 135 litres of
water per day.
We flush in the region of 33 % of our drinking water down the toilet.
Baths and showers account for 25% while our washing machines and
dishwashers take a further 21 %.1 Severn Trent have estimated that
we only drink 1 % of the water produced to drinking quality.
On a broader level, it is recognised that by the year 2025, two out of
five people in the world will suffer from shortage of water.2 Huge
quantities of valuable rainwater are lost through inadequate catchment
systems and wasteful applications to the land. Two thirds of water,
world-wide, is used for agriculture and while the world population
has increased by 100% in 100 years, water consumption has risen by
600%.
1 Barton, H. et al. (1995) Sustainable Settlements Bristol: UWE p.235. 2 Green Futures (1999) Sweetwater Postel, S. July/August, p.22.
Here in the UK, we make insufficient provision to conserve water.
Each time there is an excessive rainfall we appear to have flash floods
that damage housing developments. Many of these are post-war
developments built upon former flood plains. It is of little consolation
to learn shortly afterwards that water continues to be in short supply
because the floodwater has been directed through the surface water
system, straight out to sea.
Catchment and treatment of water is an issue of sustainable
development that must be addressed. As someone particularly
interested in wetland, it is alarming how the water-tables are being
changed by shifting consumption's of water. Ground saturation is an
important biotic function and further assists in the reception of water
to be utilised.
Water resources must be managed in a sustainable way if standards of
living are to be maintained. This may result in some regulation of
drinking water supply by metering and raising charges. The
following advice may assist those wishing to learn more and facilitate
the conservation of water.
1
Sustainable Water Supply
Water efficiency is improved by:
• Minimising the use of white (mains) water
• Collection and use of storm water (rainwater) for utility purposes
• Recycling water (grey-water) for utility and irrigation purposes
• Recycling black-water sewage effluent after suitable treatment
• Reducing the demand and consumption for irrigation
Sustainable systems can reduce environmental impact and are based
upon catchment storage. This may require considerable space.
Water Catchment Conditions
Water collection will be conditional upon:
• Climatic conditions of an area
• Land area relationships with eco-cycles
• Measurements and decisions determined by 'watershed' area
• Flow, volume and water quality will be determined by landscape
gradients
• Biophysical conditions will be affected by land, position, climate,
soil and rock formation
• Positional elements include, macro-climate (topography) meso
climate (exposure) and micro-climate (wind and sun).
Fig. 1.3
Some of the processes of water circulation in the 'hydrological cycle'.
3 Money 1972, p.58.
2
The availability of water is essential to ecology. Water supply must
be regular and uncontaminated to support plant and animal life. Water
is collected in sub-surface aquifers resulting from the infiltration of
precipitation from rain, fog, snow, frost and dew. Land surfaces
collect water that runs via gradients into water courses, or collects in
ponds and lakes. These surfaces may be designated geographically as
'catchment areas'. Catchment and collection will depend upon the
retentive qualities of the soil and rock formations. Quality may be
affected by leaching conditions and contamination from fertilisers or
industrial infiltration. Fresh water is measured for quality by the
Environment Agency. Pollutants are detected and filtered
accordingly.
Total Water Cycle Management
This involves the integration of land use planning, managing water
supply, waste-water collection, treatment and disposal. Storm water
collection and drainage services are essential within the design of this
cyclic system of management. However, where a 'sustainable
system' is confined to a small development, these elements can be
dealt within a larger decentralised management system. Three levels
of treatment are required to treat effluent to a quality sufficient to
discharge into a potable (drinking quality) standard. These are
recognised as the primary, secondary and 'polishing' stages. They
progressively decrease the biochemical oxygen demand and most of
the ammonia levels. Integration of catchment and treatment will
depend upon the size of the land available and its affect on land use.
Hydrological Function
To be fully accommodated, each land area has a position within the
hydrological cycle - depending upon topography, soil and geo
characteristics. Particularly where there are flood plains or sloping
lands. They may also be affected by, or liable to, pollution from
leaching, etc. The presence of upland forest will ensure rainfall if
managed accordingly. Vegetation provides a vital role in the
generation of rainwater supplies.
Local Water Supply and Treatment
Local water is that supplied from within the local river catchment area
and directly on site. It is important that no interference is caused to
the natural hydrological cycle. The catchment locally should be
defined. Sewage systems may be integrated with the hydrological
cycle. This can be handled 'on-site', or through the local authority
system, or an element of both. Harmful substances must be
separated, bio-degraded and reduced to a 'useable' and safe quality.
3
On-site treatment may include septic tanks, reed beds, leach fields,
solar ponds and other forms of 'digester'. Black sewage will require
large areas for treatment and may be better handled off-site.
Water Cycling
This is the process of water through an organisation such as a
household, office, farm or industrial activity. It does not need to be
of 'drinking quality' for all purposes. Quality standards can be
applied for differing purposes. Surface water drainage is the key to
the hydrological cycle. Flash flooding is disruptive and damaging.
Such collections of rainwater should be allowed to penetrate into
groundwater reserves. The areas of sealed surfaces generate 'run-off
in heavy rains and may cause problems at lower ground surface
levels.
Design Patterns
Barbara Hammond has made a study of the elements that may be
considered when approaching an on-site design proposal:
This is essentially to improve biotic productivity. Starting with the
ecological unit of the watershed. The local authority unit is organised
as a whole and 'regional boundaries' are up to the major national
water system and major rivers. Second tier boundaries - may be parts
of the above watershed's feeding tributaries. The watershed scale is
of importance in the improvement of biotic productivity. A
'neighbourhood' would be within the 'watershed'. Economic 'units'
may be households, businesses (factories, farms or estates).
The design might include 'plots' and 'blocks' that are scale collections
of units within the 'watershed'. The 'local scale' may be a political
unit or a local authority.
Flow Indicators and Aims
These will be taken from the hydrological pattern, its function, water
catchment and supply. How close is the supply? Minimal
groundwater should be extracted. Rainwater 'harvesting' should be
applied. Water is best transported by gravity. Minimum stream
water extraction. Grey-water cycling (close to use) and water supply
redundancy. Dual water and sewage treatment to reduce external
services to redundancy.
Surface (stormwater) drainage reduction by foresting upper slopes.
Creation of slow drainage, avoiding excessive 'sealing' of surfaces.
'Balancing' local floodwater treatment and reducing main drainage to
redundancy.
4
Fig.2.
Protecting Water Catchment Areas
Planning must be applied to ameliorate the effects of development.:
• External surfaces and drainage should be designed to increase
infiltration (less concrete and paved surfaces)
• Apply vegetation where possible to cleanse air and water
• A void the necessity for irrigation where possible
• Protect aquifers and water courses from pollution
• Protect floodplains from development and ensure run-off facility
• Reduce all demands for water, particularly the consumption of
drinking quality (white water).
Indicators for W ater4
• Percentage of population with drinking water below EU standards
• Per capita consumption of water
• Percentage of local demand for water met from local resources
• Changes in the level of water table over time in each district
• Capacity of both local water supply and disposal systems compared to current levels of use, by area
• Tonnes of untreated sewage discharged
• Percentage of river or stream mileage in class one category (EA)
4 Sustainable Settlements p.35.
5
Rainwater Harvesting
A large proportion of drinking quality water is consumed on activities
where such a high quality is unnecessary. Purified water is essential
for healthy drinking and bathing purposes. The water we use to flush
toilets, wash clothes, clean cars or water gardens may be less
purified.
Rainwater can be readily collected from the roofs of buildings and
stored for use as required. This standard of quality can be used for at
least 50% of domestic activities. Application can be much higher in
commercial or educational establishments. Drinking 'tap' water can
be reduced to metered efficiencies.
The collected surface rainwater is normally gravity fed into storage
tanks. From there it is pumped to various outlets. The rainwater is
filtered before entering the storage tank and a further filter is applied
to the outgoing pumped supply. Rainwater storage systems may be
fitted with sensing devices, firstly to operate the pumped output
supply on demand, and secondly, to trip over to mains supply at
times of shortage.
In an article written by Nick Bentley of 'Eco-Vat', 5 he states that
'more than 50% of the UK's total daily water requirement falls freely
on the roofs'. When accounting for an average family of four he goes
on to say:
'With a roof area of 180m2, and an average rainfall of
1,000mm, this area will, through the course of a year,
collect 180m3 of water. This means that 76% of this
household's water needs can be supplied by the property
itself .6
Potable water can be achieved if additional filtration is installed. An
Eco-Vat rainwater storage system is typically supplied complete with
all fixtures and fittings necessary for use. The collection tank is
specifically designed for rainwater storage. The tank can be installed
above or below ground. Usually it is concealed below ground and is
fitted with a screw-down manhole cover. The standard capacity of a
tank is 5,000 litres. Where necessary additional tanks can be
connected. No planning permission is necessary and the pump is
submersed in the tank. This system normally operates three-phases
of filtration.
5 Urban Design (1999) High & Dry (January p.19. 6 Ibid
6
~ .. ·~~.
~
Ud
~ uerinsert
WFF filter collector
Fig. 3.
The Green Shop, Cheltenham Road, Bisley, Nr. Stroud,
Gloucestershire GL6 7BX, are suppliers of three alternative systems.
They each incorporate an automatic switch over to mains water if
stored water is low. Each of the systems are designed to suit
individual budgets and requirements. They are fitted with 'Wisy'
filters which they consider to be the most efficient available. Various
pumps are available along with regulating controls to maintain
pressure levels. Excluding the container tanks, the price of the
systems range from c.£600 to £1,400, plus VAT.
The 'Green Shop' do not stock storage tanks which may vary in size
according to individual systems. However, they are happy to supply
from stock, re-used orange juice tanks, with a capacity of 1520 litres,
which they consider to be fine for smaller domestic installations. The
current price for these, including delivery, is around £120.
Typical costs for an Eco-Vat system, including a 5000 litres tank,
( exclusive of VAT) range from c.£1300 to £1700. Perhaps it would
take an average family seven or eight years to recover the costs of
installing one of these systems but Eco-Vat have statistics to support
costs recovered by many commercial establishments in less than 3-4
years.
7
Tundish detail
~ insect proof mesh
Minimum water level; valve turns on.
Detail to prevent sediment disturbance
pipe falls away from valve
/ 0 @ Mains water
~-------,G> r ::
__.) I~ c:=== II
(f -::-
I I I I I I I I I I I I
------~:_-1
~
soakawayorsurface ater drain -verflow detail
To we, washing machine, Garden tap etc 15mm plas1ic eg_ljepworth 6r Johri Guest (PEX).
1. Inlet from Wisy filter. 2. Mains top up via type A airgap. 3. Overflow. 4. ElectricaUy operated valve. 5. Float switch for mains top up. 6. Coarse strainer and foot valve. 7. Rainharvester pressure booster pump: 8. Flex. 9. Junction box. 10.13A socket. 11. Isolating valve.
EXAMPLE OF TYPICAL INSTALLATION USING A 1520 litre 'OJ' CONTAINER AND RAINHARVESTER BUDGET SYSTEM
Fig. 4.
Extracted from 'Rainwater Harvesting' literature of the 'Green Shop'
8
Recycling and the Treatment Of Sewage
The purposes of sustainable systems should not focus simply on cost
reduction or even the readily available and convenient supply of
water. It is important to remember that we are reducing the effects of
water demand on the mains water supplies. In a world where the use
of finite resources is being reassessed, and in an economic
environment where the cost of mains water (and sewage treatment) is
both expensive and becoming unreliable, all consumers must observe
the needs for conservation.
Greywater is a term given to effluent, contaminated by use of some
form but not to the degree of sewage, or 'blackwater'. In areas where
there is less rainfall to be gathered it may be of greater necessity to
consider the maximisation of greywater cycling.
Greywater cycling can be undertaken at various scales. Within the
household or commercial establishment, water may be cycled through
filters to eventually reach potable quality. In most cases recycled
water is brought up to a standard similar to that of rainwater or simply
reapplied. Typical 're-uses' of water would be from that used for
cooking, washing-up and bathing to be applied to toilet flushing and
garden irrigation.
Greywater cycling is of fundamental importance to the improvement
of watercourse quality. Greywater combined with stormwater will
overflow from the main drainage system at times of extreme pressure.
The two conditions of rain and greywaters should be contained within
different systems. Blackwater and greywater can be processed
together and put through a recognised three phase system of filtration.
This system employs reedbeds which can be operated locally.
Two main types of reedbed are in currently in use, the horizontal
Kickuth beds, and the vertical, Seidal beds. The vertical form
requires less room and fewer reeds to filtrate a comparative amount of
water. The breakdown of sewage requires some preliminary
treatment before entering the reedbed system. A series of deep cells
process the effluent. At the first stage there is constant silting to be
removed. Following through a bed of Common Reed or Reedmace,
it then flows through a secondary bed containing a wider range of
aquatic plants. Finally the water is cleaned or 'polished' on shallower
lagoons of finer vegetation. At this stage the quality of the water
should have reached a standard fit for discharge into local
watercourses, applied to irrigation or for utility use in house or firm.
9
Reedbed Cleansing
Sewage absorption will require an initial pond of at minimum 10m2•
This would be sufficient for a three person household and an
additional lm2 would be required for each additional person. A three
bed system would usually be employed, having common rush and
reed in a first filter pond, with bulrush and iris with reeds in a second.
The final 'polishing' stage can be formed into a stream with gravel
bed and planted with water mint, marsh marigolds, etc.
lststage Ca1't1mnn&!ed
~EY
0 Crunpleted
,-,, Pn•'-'--' '. ....... , .,...__ ...
,\~ Hummus tank \... 3rd :.ta~ iris bed
3rd stage ll<>lded truebuhush bed c· i ~ Pnlyt1Umel
I ·--· J / ...... ::::. l mariguld buJnash !~.,' f ) ., ~
"~ : .. ~·:! ............ (.) rund . Irrigation
The Eco-Cabins sewage treatment system ~ holdlngtanl;
Fig. 5.7
7 System proved at Centre for Alternative Technology (Moodie, 1995)
I ~ ir
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Ill..
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'1•· -..zj,~.,.r. •• . •1• ~,~. ""1-i,u. .... ~ ... ~ i~W' tf- § - t;. re
~ effl.,Vl!,lf IJH i,..,.,._ - ~ ~-~l!W~-~-.. OP,1,1 ,,.._ .. ~ ~1\.'! 'Ill MMM · po,M, /fr~ ,a 11.lma<T
:11'D1!MCll1" et!l>i- ~ ~iMl'-'f IIJ Wlt,IP~
M«>-~1!> ~i,«r-/,','!11JVII...~ <IP ille" wAWND
Fig. 6.8
8 Architects' Journal 18 April 1996 p.34
10
On-plot and Local Systems
Many architects and developers today are adopting 'green' processes
and secondary water systems can be seen in their show houses.
However, if there is to be sufficient improvement to 'make a
difference' we must consider a straightforward update of existing
property. Here are the stages to be considered:
• Analysis of the local watershed (quality and collection)
• Modifying the collection guttering and down-pipes from roofs
• fustalling a rainwater harvesting and filtering system ( & storage)
• Plumbing into the mains 'changeover' and supply system
• Minimising any 'sealed' surfacing and ensuring soil penetration
• Creating surface ponds where and filtration beds where possible
• Administering a strict regime of recycling useable 'utility' water
• Clear labelling of 'drinking/bathing' quality water and limitation of
any excess 'tap running'.
Case Study: . Domestic Update
The property under examination is a four storey Regency terraced
house: 13 Cambray Place, Cheltenham, Gloucestershire.
Fig. 7.
11
Fig. 8
The Cheltenham Site Boundary/ River Catchment Area
12
Fig. 9.
Location of Cambray Place
13
The Practical Application of Water Conservation
Conservation at the immediate level can simply be achieved by the
reduction of water consumption. Considerable reductions can made
by the use of water efficient WC's (1.5 - 3.0 litres versus 9 litres
conventional) or by the use of composting toilets.9 Showers can be
applied efficiently to replace the greater consumption of baths.
Scale of operations
The initial and greater level of consideration must be that of the area
watershed. This will affect the proximity quantity and quality of
water available or accessible to the developer10• Flood plain, high
water-table or sloping ground will affect the approaches applied. At
the larger scale of operation and with available land surface available it
may be possible store water in ponds or lakes. This would
incorporate the catchment of ground and surface water. It should not
include any diversion of water courses however minor in size.
At 'plot' or 'unit' scale rainwater may be collected from several roofs
and stored in a suitable pond or contained within tanks. Preferably
and where space allows it should be in ponds to be 'balanced' and
9 Refer to Appendix 10 The expression 'developer' may be applied to each scale of operation.
cleansed by natural vegetation. Wild-life is to be encouraged and
output can be adequately filtered before consumption. The cleansing
of greywater and blackwater will be dependant upon available space.
This can be dealt with adequately by grouping 'units' as necessary.
At the smallest scale, a house 'plot', in an urban environment the
'cleansing' method will be dictated by space limitations. If grouping
is impractical then the system must be limited to rainwater harvesting
from all roof surfaces, collection and containment in a tank. This can
be above or below the ground in a small backyard.
An option worthy of consideration, when gathering water from a
roof, is to retain storage at attic level and or heated by solar panels.
The collected water can then be stored at high temperatures in super
insulated thermal storage tanks. (This is truly 'green technology').
With such an arrangement the supply can be distributed in hot or cold
format.
14
Case Study: 13 Cambray Place, Cheltenham
The property is of four storey's, these comprise:
A basement flat containing 1 Bath, 2 WC' s and 1 Washing
machine. Currently this is the accommodation of one professional
adult.
The ground floor is occupied by a business (Architect's Office) and
has 1 WC. Currently this employs two adults.
The two upper floors comprise house levels and contain 1 Bath and
Shower, 2 WC's and a washing machine. Currently this is the
accommodation of two adults and two children under ten years of
age.
Plan dimensions of the rear garden are approximately 17m x 5m.
Down pipes from the potential roof catchment are conveniently
situated as is the mains water supply to be incorporated into a 'rain
harvester' system. Directly to the rear of the property is a small patio
of approximately 3m square and currently covered by small pavers.
This location would be entirely suitable to contain a submerged water
storage tank 2036mm diameter and 2428mm high. The container,
supplied by ECO-V AT will store 5000 litres of non-potable water. It
would be capped at ground surface level with a screw-down man-hole
cover.
The recommended system for these domestic and business conditions
would be the ECO-V AT Gravity Primary System. This will provide
all non potable supplies. Toilet flushing, washing machines,
dishwashers ( should they be fitted) hot water supplies and all external
uses. Specification as follows:
5000 litres net rotomoulded tank with 110mm diameter inlet and
overflow connections, tank connector for 25mm alkathene pipe, and
lockable cast iron manhole cover.
Multigo stainless steel submersible pump, supplying 80 litres/minute
at 10 metres head. 'Lift-out' service plate containing pressure switch,
non-return valve, control unit and depth sensor switch. A display
unit (to be sited internally) with manual and automatic modes, and
lights to indicate the level of water in the tank. Leaf filter requiring
maintenance every three months. Floating filter (200 microns)
attached to the pump and drawing water from 150mm - 225mm below
the surface. 'In-line' filter with removable and washable 100 micron
stainless filter. Solenoid valve to control the mains water.
15
The Local Watershed
The groundwater of the Cheltenham area is the result of the following
geology. Cheltenham originated on a 'sand-bed' (the Cheltenham
Sand) and the Chelt hollowed out a depression which has filled up
with gravel, loam and peat overspread with alluvial matter.
Subsequently the town extended onto the Lower Lias clay.
These conditions can be seen in excavations of the soil at the rear of
13 Cambray Place.
The groundwater of the Cheltenham area is not monitored by the
Environment Agency. It was recognised that the wells in the sand of
this area were ( and are) particularly vulnerable to pollution. This has
been the case since ( and probably before) the 1930' s. At one-time
there was a borehole for the Flower's brewery but that was
discontinued. Groundwater is not considered usable by the agency
without treatment and close monitoring. The Chelt Sands area are
classified as a minor aquifer with high vulnerability.
The soil is generally classified as 'slowly permeable calcareous clayey
soils ( 411 b - Evesham II but unclassified actually in Cheltenham) .11
Water levels in the sands reflect the topography mainly being
relatively shallow near the river. Industrial processes may have
compromised the groundwater quality locally.
Employing the principles of "What if', and given the space to employ
a suitable catchment pool, with an impervious bed, freshwater could
be stored. Contamination or pollution could be eliminated by the
planting of reeds and other dissipating aquatic plants. Taking up the
area immediately in front of the terrace containing 13 Cambray Place.
This area, currently a car park could be conveniently be created into a
communal lake capable of providing a functional and very attractive
landscape. A communal lake would be capable of cleansing the
surrounding prope1ties sewage disposals to a level capable of
providing a useful water garden and wild life reserve. If local 'roof
gathered water' was initially collected for personal consumption then
the overflow could be directed into the communal pool.
11 These comments by John Hiley, Hydrogeologist Environment Agency, letter to Alan Shelley 10 April 2000.
16
Fig. 10.
"'
"'
KILOMETRES
o 20 40 eo ao 100
I A- ;;;;we 0 10 20 30 40 50 1!10 MILES
Average Annual Rainfall for England & Wales 1916 - 1950
(The higher density of shading inicates the greater levels of rainfall)
17
Fig. 11. (Extract) Hydrogeological Map of England & Wales
Cheltenham area G5 Inferior Oolite (Brick pattern showing Cotswolds area)
G3 Lias ( clays with thin bands of limestone and sand deposits
18
Fig. 12. Groundwater Vulnerability Map (Extracted from NRA Sheet 29 (Worcestershire)
areas indicate major aquifer with high vulnerability
areas indicate low aquifer with low vulnerability
minor aquifer with high vulnerability
non aquifer (negligibly permeable)
NB. Other than green areas, all are highly susceptible to leaching.
19
Waste Management
All waste water (greywater) is handled conventionally. The baths,
basins, and kitchen sinks have conventional traps and wastes. With
permission (to be sought) from EA (local authority) screened water
can be passed to an approved soak:away. All waste pipes currently
run internally and connect at each floor level with an external waste
down pipe.
An additional down-pipe 50mm diameter can be installed alongside
existing waste-pipe to direct greywater into a clayware 'Hepworth'
drain 100mm in diameter. This drain should be connected to a
Hepworth clayware grease trap, to remove any grease that may have
entered the waste water from the kitchen sinks. From the grease trap
the drain would join with the overflow from the rainwater storage
tanks and pass to the soak:away, which handles all the grey water
from the house.
Permission to discharge waste water is referred to as 'sullage'. Such
permission was sought (and granted) by the authors12 of The
Autonomous House on the grounds that such waste water would be
12 Vale, B. & R. (2000)The New Autonomous House London: Thames & Hudson
P.187.
no greater in quantity than the water that would have entered into the
soil before the building was constructed. It should also be qualified
that the water would only contain soap and eco friendly detergents.
The soak:away can be constructed to a depth of around 1.5 m. This
would be excavated 0.5 - 1.0 m from the periphery of the rainwater
storage tank (into the garden). Construction of the soak:away would
be 1.5m2 of perforated brickwork on a 150mm concrete base. A
suitable concrete slab would form the top of the chamber.
The walls of the unit should be backfilled with broken brick rubble.
Although there is clay in the soil formation at Cambray Place, the
soak:away has sufficient capacity to ensure dispersal and percolation.
A bilge pump (hand or mechanically operated) can be attached to the
container and with a hose-pipe to apply irrigation water to the garden.
The capacity of the soak:away is estimated to be 1,350 litres plus, and
will safely handle any unforeseen excess intake. Neighbourhood
schemes would involve an overflow from the individual soak:aways
into a communal pool.
Without an available overflow pool facility, excess water may flow
(in its limited amount) into the local surface water drainage system.
20
Facilities at house/plot level
Well-water, bored locally, has been ruled out as unsuitable in the case
study of Cambray Place. However, in alternative circumstances, and
where watercourses are not affected, low level supplies from a bore
hole may be considered.
Rainwater harvested at roof level can be held via storage tanks ( at
ground level) pumped to header tanks installed in loft or large airing
cupboard space. Header tanks could be dedicated a) to roof collected
rainwater and b) to solar heated rainwater contained within super
insulation to retain heat.
A solar system can preheat water to be retained at high levels for
gravity distribution. A collector of roughly 6m2 in area, positioned on
the roof will heat sufficient water to satisfy a household in summer
with around 2000 kW'h of energy. Of course this will vary
considerably throughout the seasons. In the case of 13 Cambray
Place, three evacuated-tube, solar water heaters, mounted uppermost
on the south facing wall, will allow heated water to thermosyphon to
storage tanks accommodated as above. It is reasonable to assume that
solar energy may also drive circulation pumps where required.
Alternatively a small wind driven generator, installed on the roof of
13 Cambray Place, could operate efficiently.
Water and sewage treatment if handled autonomously would reduce
domestic running costs considerably. At the same time it will relieve
the overburdened 'local systems'. During times of 'main supply'
shortage, self sufficiency may alleviate national problems while
ensuring ready supplies to the self sufficient.
Results of tests carried out13 at the Nottingham Trent University
proved surprisingly high standards of rainwater collected from roofs
in the Nottingham area. The physical and chemical characteristics
from collection tanks, excepting turbidity, complied with World
Health Authority standards for drinking water.
Water collection is via guttering (pref. copper) in order to fit standard
diversionary fittings. Leaf traps may be necessary according to
prevailing conditions. Pressure pumps can be activated when a tap is
turned on to supply water directly. Alternatively, water held in the
header tank can be fed via pump and drawn via ball valve and gravity.
13 The Autonomous House
21
Roofs inhabited by pigeons and other birds may provide contaminated
water that will require purification. In-line filters that remove disease
organisms may be considered if pollution is likely to occur.
Reduction in water consumption will be achieved by replacement of
conventional toilet units. It is estimated that a saving of more than
20% of the total consumption can be achieved. Disposal of sewage
by conventional means includes a waste of potential fertiliser and a
loss of flushed (purified) water.
An option can therefore be provided, to replace one or more of the
toilets with a 'dry' unit. The Swedish Mullbank toilet is comparable
in size to a conventional toilet. It uses a 140W electric heater,
combined with a 21W ventilation fan, to accelerate aerobic
decomposition. Output from the toilet is considered 'safe' to be
distributed on garden plants and vegetables.
Composting toilet units seldom need cleaning ( compared with
conventional water flushed units) .. Smell is minimal and liquid
removal, pumped into a bucket (at intervals of five to six weeks) can
then be applied as fertiliser. The liquid can be diluted to water tomato
plants or poured around the base of trees, shrubs or hedges. It also
provides an excellent activator on compost a heap.
Water consumption of five-person14 (sustainable) household
I/head/day Table 1.
2 (3 washes/week)
2 (2 washes/day)
5 (as conventional house)
5 ( assumes occasional use of basin
16 (4 showers of 20 1/head/day)
34 I/head/day
170 I/day
Water consumption comparisons Table 2
UK house Sustainable %
(1/head/day) house reduction
45 21 53
15 6 60
15 2 87
5 5 0
10 0 100
20 0 100
50 0 100
160 1/hd/day 341/hd/day 79
800 I/day 170 I/day
14 3 adults & 2 children. Table info taken from Vale, b & R, Autonomous House.
22
Domestic hot-water demand in use Table 3.
total consumption cold water hot water
(I/head/day) (1/hd/day) (1/hd/day
6 6 0
2 0 2
5 5 0
5 0 5
16 10 6
34 21 13
170 105 65
Further to pumping of hot ( or cold) water: A photo-voltaic panel
would provide enough solar energy to power a pump/s. The solar
radiation required, would correlate with the occasions when solar
heated water is circulated to the insulated hot water storage tank/s.
The temperature of stored hot water could be topped-up by the
addition of a conventional electric immersion heater. As previously
suggested, the system's energy performance could be improved by
the addition of a wind turbine (installed on the root). This would
smooth the seasonal discrepancies.
Community and Economics
In both short and longer terms, the benefits of adopting sustainable
practices are manifold. Economically, as the household unit gains in
energy savings, excesses beyond the needs of the household can be
passed on through the plot scale into the neighbourhood.
A major gain and perhaps most important benefit, is that of
community. While not necessarily being reliant on immediate
neighbours, it is likely that a 'common' ideal towards sustainability
will gain 'community' values. These will aid both physical and
economic support and increase levels of security.
An example ( on a 'What if? principle) of how an urban
neighbourhood could be converted to be more sustainable, is shown
in figure 16 on page 32. The communal resources are coupled with
the need to participate in an organic environment. Such conditions
should generate a more neighbourly and caring community.
23
/
Fig. 13. Unit (house) level: 13 Cambray Place, Cheltenham
24
Fig. 14. Plot Level: Cambray Place terraced block
25
Fig. 15. Neighbourhood Level (Primary locality) Cambray Place, Cheltenham.
26
THE WIDER SCALE
Regulation Imposed at Local and Watershed Levels
Significant improvements can be made to the existing water supply
and waste removal systems to reduce costs economically and
ecologically. Firstly, let us clarify a few facts about 'locality'. This
refers to a district within the overall designated 'watershed'. The
watershed is a geographical area determined by its catchment from
defined watercourses. For the purposes of regulation or moderation,
it will normally be of a size that serves a community and its suburbs.
The unit and plot scales have been previously explained. The
references to 'neighbourhood' may require clarification.
A neighbourhood is generally a close community of mixed people,
with common needs, that share experiences and mutual support. It
will also be seen as a 'place' (e.g. neighbourhood/community). It is
possible to significantly reduce their water consumption without
affecting the comfort of occupants. This is dealt with initially by:
• Installation oflow-flush toilets or modification of older versions
using 'Hippo' bags, or similar, to reduce flush volumes.
• Application of composting toilets.
• Installation of aerating sink/basin taps and aerating showerheads.
• Flow restrictions
• Incorporating a greywater and possibly (space permitting)
blackwater recycling system.
Firstly, we may consider those actions that will bring us nearer to an
autonomous and sustainable situation. Drinking (potable) water is
collected from rainwater, then stored underground. A long dwell time
between inlet and outlet pipes will enable particles to settle down on
the bottom of the tanks and provide relatively pure water. However,
to avoid discrepancies, the water is passed through a 5µm string filter
(or similar) to remove any remaining small matter. It may then pass
through a carbon filter to remove any dissolved chemicals or foreign
matter. The water can then, if necessary, be further subjected to ultra
violet light to kill any suspected unhealthy remaining bacteria or
viruses.
Drinking water points in most domestic buildings will be limited to
the bathrooms and kitchens. The catchment of roof-surface rainwater
is ideally via copper gutters. This will avoid lead contamination and
reduce the use of PVC. The manufacture of PVC is both dangerous
(PVC off-gases) ad the material is difficult to dispose of at the end of
its useful life.
27
Non-potable water, collected from road and paved surfaces is
channelled into an open reservoir. The water should pass through a
'sand filter' before effecting any uses. This water will then be of a
standard suitable for bathing, flushing toilets or cleaning cars, etc.
Sewage treatment can also be dealt with quite locally. Sewage from
soil pipes ( clayware) with minimal slope, would collect water from
utility/kitchen sink, toilet and basins to run into a sewer. This enters a
septic tank with around ten days retention (to settle) the overflow
from which runs into a reed bed.
The arrangement of the reedbed ensures a long dwell time in the reeds
( up to three months) to a level of purification before finally passing
through a limestone gabion wall into a reservoir lagoon. W astewater
treated via reed beds supports a highly active eco-system. The roots
of the reeds supply oxygen to bacteria in the water that digest
pathogens in the sewage. No smell or faecal coliforms are liable to be
found in the reservoir. The water of which can effectively support
fish on its nutrient rich quality and will be pure enough to reach EU
bathing standards.
From time to time, it will be necessary to provide low maintenance to
remove blanket weed and unwanted over-growth from the reedbeds
and lagoon.
Annual management can be reckoned at around:
Lagoon maintenance @ two man days per annum, say
Emptying septic tanks @ half day p.a., say
Changing filters etc. @ one-man-day p.a., say
Maintenance of sand-filters @ two-man-days
Replacement of new filters at an approximate cost of
A rough total of these expenses amounts to
(£150)
(£35)
(£75)
(£150)
(£50)
(£460)15
These costs represent very large cost savings against the regular
charges made by a local water authority. Reed beds and 'sewage
gardens', however, do take space. Their application very much
depends upon the nature of the community and conditions of the land
space available. Shared facilities are inevitable and desirable to lessen
the pressures of development. Although it is unlikely that full
autonomy can be reached, the reduction on valuable resources and the
costs cutting will be very significant indeed.
If residents and businesses are to accept responsibility for their own
wastes, robust local management systems must be devised.
15 These figures extracted from information within the 'vision statements' of the Hockerton Housing Project, 1999.
28
Management at Town or Locality Scale16
• Town sewage can be treated by an advanced tertiary works,
producing compost for reuse on the land and a liquid effluent of
high enough quality to raise fish.
• A 'wet-dry' system of waste management will recycle up to 85%
of the town's wastes through a composting plant and materials
recovery facility.
• A community utility will control the pricing of energy and water to
encourage efficiency and discourage use during peak-demand
periods.
Watershed
Environmental Infrastructure:
All watercourses will be protected from developments and pollution's
from adjacent industrial or agricultural activity. Asphalt surfaces
should be limited or removed to reduce chemical run-off.
Physical Infrastructure:
Storm drains, that normally channel run-off water into river and sea,
can be replaced by a system of grass swales designed to maximise the
reabsorption of run-off back into the land.
16 Ideals extracted from those developed for the Canadian 'Bamberton' town project.
Guy Dauncey (1994) Incontext
New Developments:
Regeneration on the rural fringes can employ open ditch surface water
channels to handle 'local' flash-flood rainfalls. Excess water would
be directed into the outer grass swale system.
National Water Resources
River water quality may be poor in areas, resulting from urban
contamination. This may occur where surface run-off from roads and
industrial areas introduce contaminants. Unattenuated run-off from
developments increase the risks of flooding from the receiving
watercourse and can damage the river habitat.
Flood water coursing down rivers reduces the available water
resource. Rainwater should preferably be able to percolate into and
soak the ground.
Abstraction
This has not been closely regulated in the past. Many abstractions
have been carried out 'as of right' by private land owners. This must
now be tightened. The farmer will need to have an abstraction licence
from the Environment Agency in order to fill a private reservoir.
Planning permission and 'winter filling' should also be required.
29
Rainfall normally drains into watercourses via surface water outfalls.
Contaminated discharges may include oil, organic or toxic matter.
Cross connections of foul sewers into surface water drains also
occur. The result of these contamination's can severely degrade
urban rivers.
To minimise the impact of environmental problems arising from
conventional drainage, design attention can be applied to the process
of reducing pollution. Protection of rivers and groundwater requires
changes to the drainage system. Treatment facilities should be
introduced, prior to discharge into the watercourse or reservoir.
Sustainable Urban Drainage Systems (SUDS)
There a flexible series of options. Structural techniques can reduce
the impact of surface water discharges. These should be included in
future developments. Local authorities are being encouraged to
include SUDS in strategic and local plans.
Discharges of site drainage may also be regulated by the Agencies
under the law on water pollution. The regulation of surface water
discharges is a discretionary power and the Agencies are seeking to
encourage 'good practice'.
Surface water discharges to soakaway systems are subject to control
under Water Pollution Regulations, including the Groundwater
Regulations 1998, where List I or List II substances are present. Any
discharges should be in accordance with the appropriate Code of
Practice.
Planning guidance can be provided on surface water drainage using
source control techniques both within units or plot areas as a whole.
Such circumstances would include the use of rainwater butts, wet and
dry ponds and storm-water wetlands.
Surface Water Quality
Rain falling on impermeable surfaces becomes contaminated by dust,
oil, litter and organic matter. This flushes into a watercourse where
conditions may result in silt blanketing and a reduction in oxygen
levels. Life in receiving streams may be severely restricted.
Where discharges soak into the ground, the quality of the
groundwater may be affected. Foul drainage from incorrectly
plumbed toilets, washing machines or dishwashers may contaminate
rainwater systems
30
Flooding caused by impervious surface areas may occur at some
distance ( down stream) from the source. Balancing ponds or similar
measures can compensate for this. By increasing permeable ground
areas, allowing water it to infiltrate, we can improve levels of
groundwater and base flows in streams. Flood generated high flow
rates, for short periods, can have dramatic affects on river habitats.
Irregularly increased flow rates can erode riverbanks and beds and
shift silting matter downstream. Such conditions will alter the natural
flora and fauna of the river habitat and ecology.
SUDS may provide treatment for water prior to discharge, by
applying the natural processes of sedimentation, filtration, absorption
and biological degradation. Systems can be designed to improve
biodiversity in urban areas. Ponds can be designed as a local feature
(re Cambray Place) for recreational purposes and to provide valuable
wildlife habitat in urban settings.
SUDS fall into three broad objectives:
• Reduce the quantity of run-off from site ( source control techniques)
• Slow the run-off to allow infiltration (permeable conveyance)
• Provide passive treatment to collected surf ace water ( end of pipe)
SUDS offer a number of benefits over conventional drainage
systems:
• may protect and enhance water quality and biodiversity in urban
streams;
• may maintain or restore the natural flow regime in urban streams;
• may protect people from property from flooding, now or in the
future;
• may protect urban watercourses from pollution caused by
accidental spillage's and misconnections;
• may allow new development in areas where sewage systems are
already at full capacity.
SUDS can be designed to be sympathetic with the environment and
the needs of a specific community. The systems will allow
groundwater to recharge where appropriate and for better control of
wet and vulnerable areas. The success of the system relies very much
on the involvement of developers with planners and authorities from
the earliest stages of the development process. Systems will include
filter drains, infiltration basins, swales and integrated balancing
ponds. Detention basins designed to hold back storms or retention
ponds that will treat water and create wetland (wildlife) landscapes.
31
Fig. 16. 'What If' Cambray Place's Water Supply was Sustainable?
(An urban 'organic' and 'community' landscape)
32
Reedbed Cleansing Figs. 17 and 18.
The accompanying photographs, were taken at the
'Hockerton Housing Project', a sustainable
development, at Newark, Nottinghamshire.
These cleansing beds have been furnished with reeds,
planted in floating troughs submerged below the
surface. For maintenance purposes they both
'contain' growth and their mobility enables them to be
drawn to the bank when required.
Sewage passes through a sewer into a septic tank,
where it settles (10 days retention) and outflows into
the floating reedbed. The arrangement of the reedbed
ensures a long dwell time in the reeds (c. three months).
The treated water is finally cleansed by passing
(filtered) through a limestone gabion wall into the
main lagoon.
The lake water, while clean enough for EU bathing
quality, is also nutrient rich for fish rearing and
wildlife support. Altogether an attractive landscape.
33
APPENDIX 1 THE ENVIRONMENT
Groundwater
Groundwater forms part of the natural water cycle and is contained in
certain underground rocks or aquifers. abstractions from
groundwater in England and Wales account for around 35% of the
public water supply.17 Some aquifers also provide water supplies for
abstractors who cannot, or prefer not to use the public mains.
Groundwater is an important source of water for agriculture and
industry.
Some groundwater' s naturally feed surface waters through springs
and by base flow to rivers. This recharge is important in supporting
wetlands and their ecosystems. Extraction or diversion of
groundwater can affect total river flow, causing problems with low
flows. This may significantly affect surface waters and the quality of
water standards.
17 Environment Agency (Viewpoints, www.environment-agency.gov.uk . .land-use/water-res, May 2000)
Groundwater resources are replenished by rainfall, primarily in winter
when evaporation losses and vegetation uptake are at a minimum.
Low winter rainfalls can result in summer-time droughts.
Groundwater' s can be vulnerable to contamination. Under the Water
Resources Act 1991 it is an offence to pollute groundwaters. The EU
Directive on Groundwater (80/68/EEC) requires specific measures are
taken to prevent pollution by chemicals. There are two categories:
List I of those that must be prevented and List II of those that should
be minimised.
A study of groundwater pollution by the Agency in 196618 found 210
sources of pollution were affecting 251 abstractions. Of these 114
were public supply and 137 private supply boreholes. Many others
were found to be at risk of pollution.
The Policy & Practice for the Protection of Groundwater for England
& Wales (1998) provides a classification of the vulnerability of
groundwater to pollution. This is comprised of detailed maps on a
scale of 1:100 OOO. Additional protection to groundwaters apply to
nitrate pollution, referred to as Nitrate Vulnerable Zones (68 areas).
18 Ibid
34
Freshwater Quality
The Environment Agency monitors water quality under the Water
Resources Act, 1991. The quality of river and canal waters are
reported every five years. In the past they were simply classed as fair
or poor or bad. Since 1978 there has been a more formal scheme of
classification. Stretches are now indicated as Class 1 from A to B =
good or fair. Then Class 2 = poor, Class 3 = poorer to Class 4 being
bad. The scheme measures the presence of dissolved oxygen,
biochemical oxygen demand and ammonia. Other chemicals found
present are also recorded. Similar quality standards apply under the
EC Directive on Surface Water Abstraction (75/440/EEC). The
Agency also examines stretches of fresh water for nutrient and
aesthetic qualities under a General Quality Assessment scheme.
Water varies to some extent even along individual stretches of a
watercourse. It can be classified wrongly from one year to another
because of the analyses of 36 separate, instantaneously taken ,
samples of water. In consequence stretches of rivers are upgraded or
downgraded without any real changes having taken place!
Bathing Water Quality
The quality of bathing water in England and Wales is monitored
against standards laid down in the bathing waters regulations (SI
1991/1597) which give effect to the EC Bathing Water Directive
(76/160/EEC). Up until 1998 this applied to coastal waters. In 1998
nine inland bathing waters (lakes and rivers) were also designated.
The bathing season in England and Wales is taken to be 15 May to 30
September and sampling begins two weeks before. At each site 20
samples are taken at regular intervals ( each week). Each sample,
taken 30 cm below the surface, is analysed for total coliform bacteria
and for faecal bacteria. The latter being indicative of the presence of
traces of human sewage.
The imperative standards, which should not be exceeded, are 10,000
total coliforms per 100 millilitres (ml) of water and 2,000 faecal
coliforms per 100ml of water (i.e. at least 19 out of the 20 taken)
must meet these standards, plus other criteria.
Bathing waters are also analysed (under EC Directive) for the
presence of enteroviruses, and two samples for the presence of
salmonellae. Compliance with the mandatory standards of the EC
35
Directive have been increasing in line with recent investments by the
water service companies. Much of the publicity, if not all, has
applied to the Seaside Awards and 'Blue Flag' scheme for safe clean
seaside resorts.
Surface Water Abstraction
Water sources, such as rivers, lakes and reservoirs are collectively
known as 'surface waters'. The Surface Water Abstraction Directive
(75/440/EEC) applies to sources of drinking water. The Directive
does not control the actual amount that can be abstracted, that is
governed by an abstraction licence.
The Directive has three aims:
• To set standards for abstracted surface waters.
• To ensure abstracted water is given appropriate treatment.
• To improve the overall quality of surface waters used for drinking
water.
Surface waters are classified by the level of treatment they require and
by their suitability for abstraction. This is classified as follows:
• Al: Only simple physical treatment and disinfection necessary
• A2: Normal physical/chemical treatment and disinfection required.
• A3: Intensive physical/chemical treatment, extended treatment and
disinfection are required before the water is suitable for public
supply.
The Directive sets out different standards for the above classes:
• Imperative 'I' values, which are standards that must be met, and
• Guideline "G" values, which should be achieved where possible.
At times of exceptional weather conditions (such as floods) and
natural enrichment by substances leaching from soil, the Directive
allows waivers.
The Directive does not cover abstractions which are for private supply
(lakes in private grounds), nor does it cover abstraction from
groundwater.
36
Flooding
Although there is insufficient water, from the public supply, at certain
times of the year, at other times there is an uncontrolled excess.
Flooding normally occurs as a result of rivers and canals
overflowing, by tidal surges in estuaries and by the impact of the sea
directly on low-lying coastal land. Under the Water Resources Act,
1991, the Environment Agency is responsible for exercising
supervision over all flood defences. Their main responsibility is for
rivers, defined on statutory maps and for sea defences in areas which
are not privately owned.
River channels can only carry a given amount of water and heavy rain
or sudden melting of snow can cause them to overflow. When this
occurs, the excess flows onto low-lying areas. These may be
designated flood plains. Periodic inundation of low-lying areas have
always been a natural and potential source of soil nourishment. Flood
plains make up approximately 10% of the land area in England and
Wales. An estimated 5.8 million people live on them. 19 In some
areas, the rate of development on flood plains has more than doubled
in the past 50 years.
19 Ibid
Flood plain development has reduced the space available to store and
slowly transport floodwaters. This has forced an increase in the
speed with which floods move downstream and the maximum height
that a flood can reach. Hard surfaces of roads, car parks and
buildings rapidly increase the transfer of water into the rivers. This
excess of water at times and the very impact of development on the
flood plain has an adverse affect on the ecological and archaeological
value of the land.
Flood defences of all kinds have become essential in some areas to
protect human life. They protect property and reduce an element of
risk. Climate changes suggest, as well as becoming more windy, the
south of England will become hotter and drier. The north west is
likely to become wetter. Storm damage is forcasted to become more
frequent with effects on flooding and erosions of coastal areas.
The Agency currently maintains 36,000 kilometres of main river
defences. These include embankments, flood walls, flood relief
channels and culverts.
37
Households
Households exert pressure on the environment by using energy,
water and generating waste. Twenty per cent of all water supplied is
consumed by households, and 5% of controlled waste is generated in
the home.20 There is a steady increase in the numbers of households
and this is projected to increase at a faster rate in the next 20 years.
The increase in the number of households is projected to contribute to
the expected increase in the area of land in urban use and hence a loss
to the rural environment. Some 169,000 hectares (1.3% of England's
land area) are projected to change from rural uses to urban uses
between 1991 and 2016, i.e. a rate of 6,800 hectares per year. By the
year 2016, 11.9% of England's land is predicted to be in urban use
compared with 10.6% in 1991.
In England and Wales we each currently consume about 140 litres of
water every day. Household use of water has increased significantly
over time. This reflects changes in household appliances, lifestyles
and expectations. Efficient use of water is necessary to reduce or to
minimise the increasing demand for water. Toilets and baths use
more than half of the water in the home
20 Ibid
A five minute shower instead of a bath can save an average of 55
litres of water. Heavy duty plastic bags ('Hippos') and other devices
can reduce the amount water used to flush toilets. The use of water in
the garden and for irrigation has increased rapidly in recent years.
Most of the water used by households (80%) is returned to rivers or
estuaries after sewage treatment. Natural human waste contributes
organic matter and nutrients such as phosphorous in sewage. Some
detergents also contain phosphorous, although changing formulations
have led to a decline in the 1990s. Metal and chemical products are
widely used in the home. Some metals are dissolved from water
pipes and solder, other substances including metals are included in
toiletries, medicines and domestic cleaners.
Sewage-treatment normally reduces these to harmless levels but it is
not always known what these harmless levels are. Recent work has
suggested that some substances may have a harmful affect on the
environment. The use of pesticides and herbicides in gardens,
misconnections from 'soil' plumbing and misuse of road drains for
oily residues create problems in fresh waters. More than 1,000 water
incidents in 1995 were attributed to domestic or residential premises.
38
APPENDIX2 FLOODING
The River Chelt and Flood Alleviation
In the past Cheltenham has suffered flooding by the River Chelt.
There reference to major flood events from 1731 onwards. Floods
causing damage and disruption occurred in 1805, 1830, 1855. 1875,
1924 and 1931.
More recently, a major flood event occurred on 30 May, 1979, which
caused considerable damage and disruption. Following this, the
Borough Council carried out some diversions to alleviate such a
reoccurrence. However, there have been further flood events in
1981, 1992 and in 1993. During the last of these, on 13 January
1993, several properties were flooded, one of which to a depth of
over a metre.
Overtopping and flooding occur within about two hours of the onset
of heavy rain. The river system, through and above Cheltenham, has
been significantly affected by man-made features. Within the present
borough boundary exist the previous sites of at least seven mills.
Today only four actual mill sites exist, three with major spillways or
weirs, and three with associated buildings. In many places the river
now flows along elevated channels associated with the mills and not
in the valley bottom.
In the town the river has many road crossings (some with limited
capacity) and it is often concealed in culverts or hidden behind walls.
Through the town centre the river is mostly culverted in work carried
out between 1820 and 1834, with the remainder completed before
1855.
Today, the scheme has incorporated new flood defences, mainly
consisting of replacement culverts beneath the town centre. The Chelt
was re-designated a "main river" in 1995 and has undergone analysis
by the Environment Agency. A comprehensive scheme has been
carried out to compliment the alleviation work already undertaken.
This has included by-pass culverts, channel improvements and flood
storage.
The Environment Agency has a duty to carry our environmental
impact assessments on all its operational works. This includes
protection of ecology, archaeology and landscape/townscape. A vital
part of the scheme has been to convert Dowdeswell Reservoir to a
flood storage area. This not only protects Cheltenham from severe
flooding but provides environmental benefits for wildlife, etc.
39
APPENDIX 3.
'Cotuit' Dry Toilet Cutaway Diagram
K. - Back wall mount for hinge strapsl. - Clamp down assemblyM. - Flush toilet interchange riserN. - Notch in riser for stool leg0. - Clip to hold upper assembly upP. - Flush toilet closet flange adapter
Fig. 19. 'Cotuit' Dry Toilet
.. -.---·*_..,..--,---,-
A.
Inner door B.
Inner door slide pins c. Inner door catch & adjustn
D.
Inner· door pivot handle
E. Inner door
, latch F.Air
Urine diverte1 gutter H. Urine anti-spl pad I.
Manure bin J. Hinge strap for bin
The diagram shows toilet with flush toilet interchange kit.
This unit is a small domestic self contained waterless toilet
Fig. 20. Domestic W.C. proportions.
The unit is airtight, and has an integral urinal which takes off the urine
before mixing with the manure, making it pathogen free and safe for
use in vegetable gardens. Urine separation is also critical for keeping
the compost bin from becoming anaerobic from excess liquid.
Specification:
Top Section: is one piece of fibreglass bonded to epoxy plywood.
Manure Bib: is injection moulded HDPE stack & nest tote with lid.
Manure Bin capacity: OLNA mode; 5 person weeks.
Dehydrator mode: 15 person weeks. Volume 11.8 gallons.
Urine Tank: Available in sizes Of 5 through 55 gallons dep. on space.
Overall dimensions: 29.5" long, 20.5" wide, 21.5" tall.
Vent Fan: 12 or 24v DC, or 250v AC, approximately 5 watts (2" Vent)
Inner door closure handle: l" schedule 40 PVC. White or grey.21
21 http://www.cape.com/cdt/specs.htm NB. This is a USA product.
40
APPENDIX 4. PRESENTATIONS
'The Commodity of Water' (Seminar 30.3.00)
I acknowledge the dire problem of Global water shortages but will
confine my talk to more local issues.
Each time we have on excessive rain fall we appear to have flash
floods that affect new, perhaps unsuitable, developments on prior
flood plains.
This often occurs after a period of drought and water rationing. Once
released, the water escapes through the system and out to sea.
Catchment is an issue that must be addressed.
As someone particularly interested in wet land, I am alarmed at the
shifting levels of the water tables.
Drinking water is expensive and the consumption of drinking quality
is rising rapidly. I shall be addressing the subject of water
sustainability in view of the increasing demand and the needs for a
more balanced environment.
'Sustainable Water Supply' (Seminar 11.5.00)
At my previous presentation I mentioned the need to curtail the
squandering of valuable water. You may recall my comments on the
alarming changes to water tables and the need to arrest this situation
and to sustain water supply. To bring this into perspective we can
acknowledge two current events.
Firstly, the severe drought that exists in Africa and in India, coupled
with the fact that the India's population is rising at an alarming ( and
unsustainable) rate. Secondly, and close to home, we have just
experienced an extended spell of very wet weather. This may lead
people to believe we have an unlimited supply of available water.
However, in global terms, deeper wells are now being bored to
access water. Clearly the world's water aquifers are reducing to
levels that are causing concern for the future. Such low levels of
water can easily become contaminated by salinity when falling below
a certain level.
In order to address world shortages we may begin at where we may
invoke changes. My project concerns the up grade of local supply.
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Brief Summary and Conclusion (Final presentation 15.6.00)
'Sustainable Water Supply' is the subject of balancing demands. Key
words are: drought, dry, flood, expense, public awareness and
conservation.
People in the UK don't generally recognise the real problem of water
shortage, maybe the occasional cutbacks in severe dry spells. We are
an island, surrounded by water and receive fairly regular rainfalls.
Water Companies are under some scrutiny, mainly for economic
reasons, to repair leaks and to keep rivers free from pollution, etc.
If a serious shortage arises, it is likely the Govt. will pass legislation
to make meters compulsory. It is generally believed that when asked
to pay more for water, there will be a marked reduction in
consumption. Currently demand is escalating, and in fact a 'paying
for what you use' policy should be encouraged - to support a
'sustainable' future. This would mean abolishing standing charges
and metering supplies, even including private abstractions.
Focus groups may argue that this fairness to mankind can have
adverse effects on the environment. A planned approach should be
implemented to ensure the environment is sustained for the future.
Ruskin wrote:
God has lent us the earth for our life, It is a great entail.
It belongs as much to those who follow us as it does to us
And we have no right by anything we do, or neglect to do,
to involve then in unnecessary penalties, Or to deprive them of
the benefit we have it in our power to bequeath.22
Global issues are acknowledged but with little fear or concern. However,
there is considerable concern among environmentalists regarding climate
changes.
Actions taken by the individual at primary consumption levels can rapidly
alleviate the escalating demands for water. By minimising the use of
mains water, collecting rainwater for utility purposes and re-cycling
greywater for irrigation. If society can be influenced, not simply by moral
duty but by penalty and taxation, a great deal may be achieved. New
planning regulations and design techniques will provide efficient processes
that conserve water and energy. This is not simply an argument to secure
the future of mankind. In recent years we have seen a rapid decline in
semi-wetland ecology, resulting in the decimation of much of our popular
wildlife. This can be addressed by the appreciation of 'sustainable water
supply'.
22 J. Ruskin (1819-1900) Collected Works (ed Cook, E. & Wedderburn, A. (1903-12)
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llt could yet et worse LEESANDERS
Gloucestershire has been particularly badly hit by the latest deluge, with the Severn still risil'IIJ. Much of Tewkesbury is flooded and the muddy water is now lapping at the doors of its Norman abbey • =
By Charles Clover Environment Editor
IT WASN'T going to be long, given the biblical scale of the flooding over the past few days, before questions were asked about the .effectiveness of the embattled Environment Agency and its chief executive, Lady Young.
Baroness Young of Old Scone, to give her full name, is a Scot who
has benefited twice from the patronage of the Labour govern
, ment, fast by her appointment as a working peer and second by being given the £163,000-a-year job as chief executive of the agency.
Given how unpleasant Labour MPs were about the handling of the Easter floods of 1998 by Lord De Ramsey, a predecessor and a Tory appointment, it is a measure of the regard in which she is held that the daggers have stayed sheathed for so long.
Lady Young has now been
accused of writing off the June floods as a one-in-200-year event and then falling back on the lame excuse that the July floods happened because you cannot always prepare for an awful lot of rain.
Some of the mud will stick. Everyone knows that the agency's temporary flood barriers for Uptonupon-Severn failed to arrive in time because· the barriers. were stored an hour'~. drive away, and . the agency operatives were held up by flooding on the motorway.
What any inquiry is likely to be
told, though, is that the barriers would have protected' 30 houses out of 10,000 flooded and such was the storm that they were likely to have been overfopped.
Peter Ainsworth, the Tory environment spokesman, yesterday: reported nothing but praise from the emergency services for how agency staff behaved under duress.
An inquiry would · be equally reluctant to judge the agency's performance on one drop in an ocean of human misery. It would find that no single flood defence failed
( otper than at Upton-upon-Severn) in tpe job it was designed to do ~ protect against a 011e-in-100-year flood.
If one wants to criticise the agency, or Government policy on flood defence, one has to look wider. David Fursdon, president of the Country Land and Business Association, raised an important issue at the waterlogged Royal Welsh. Show yesterday when he accused the agency of failing to prioritise flood protection over the other statutory responsibilities it
WEDNESDAY, JULY 25, 2007 j THE DAILY TELEGRAPH
has for, say, water quality and policing exports of waste. Put it another way, does the agency have too many responsibilities? Its predecessor, the National Rivers Authority, did a more focused job.
Mr Fursdon also accused it of not being strong enough to ask for adequate funding from Government for flood defence. Others have asked why there is no drainage engineer on its board. .
Those sound like the right criti. cisms. But a truly independent inquiry chairman would under-
www.telegraph.eo.uk/news
stand that the agency must not be made a scapegoat for the failures of the government itself, which has rejected or not acted on 25 pieces of advice about flooding since 2000.
What kind of flood was this should be his fast question. And has a one-in-100 year event become, say a 1 in 50 year one in the light of climate change? Ministers were warned they should have reassessed the risks three years ago. My bet it was them, not the agency, that slept on their watch.
That sinking feeling again: The flood has been described as a one·in-100.;year event. Not so for Tewksbury in Gloucestershire and its historic abbey, where the overflowing waters of the Severn and Avon engulfed the town and left it marooned ooth in 1947 and this month. These two pictures, taken 60 years apart, show the extent of the devastation. This time hundreds of thousands in the county have been left without running water. The waters are beginning to subside, but a severe fllood waming remains i111 place
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