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TOWN AND COUNTRY PLANNING ACT 1990.
MARGATE AND BROADSTAIRS WASTEWATER
TREATMENT SCHEME, SOUTHERN WATER SERVICES L TD.
REPRESENTATION BY CPRE WITH RESPECT TO
APPLICATION No 3; CONSTRUCTION OF TWIN WASTEWATER AND TREATED EFFLUENT PIPELINE
BETWEEN THE MARGATE HEADWORKS AND WEATHERLEES WASTEWATER TREATMENT WORKS. ( Ref.
TH /04/ TEMP /0024 ).
1. SUMMARY
OF REPRESENTATION
1.1 The proposed disposal-to-sea of
up to 20 MI/day of treated effluent constitutes unacceptable wastage of a
scarce and strategically valuable resource in a region subject to a
progressive deterioration in the water supply / demand balance and increasing
stress on the water environment. The scheme also conflicts with Southern
Water' s own declared policy of supporting the re-use of treated
effluent as a key element in the integrated management of the region's water
resources (Ref 1 )
1.2 We therefore recommend that
Application No 3 be amended by removal of the return ( Weatherlees -Margate )
pipeline works and substitution of a facility for discharging the treated
effluent to the River Stour as a means of augmenting river baseflow; with the
possibility , in due course, of re-abstracting a proportion for public supply.
2. CPRE
AND WATER MANAGEMENT.
Having in mind the planned increase in
house construction throughout north and east Kent over the next 25 to 30 years,
and the accompanying growth in demand for water supply and treatment facilities,
CPRE is of the view that measures should be taken by the appropriate
service-providers and industry regulators to ensure that any schemes devised for
delivering these services reflect best practice in the sustainable management of
the region's water resources and the protection of our most vulnerable river and
wetland habitats. Given the delicate balance of Kent's river and groundwater
resources, we would look to the regulating authorities to ensure that in
assessing the options for sewage treatment, full consideration is given to the
wider implications for the integrated water management strategy now being
formulated for the South East Region. The current application is a case in
point, insofar as the waste-water in question represents a resource which could
be deployed to meet future growth in public-supply demand; thereby minimising
dependence on new sources of supply and assisting in the increasingly
challenging task of maintaining flows and levels in our spring-fed streams and
wetlands.
3. STATEMENT
OF GROUNDS FOR REPRESENTATION AGAINST DISPOSAL -TO -SEA.
3.1 The scheme, as proposed by
Southern Water Services (SWS), provides for the transmission, over a total
distance of approximately 24km, of up to 20Ml/d of wastewater, treated to
standards compliant with the European Urban Wastewater Treatment Directive,
for disposal to sea.
3.2 It is the view of CPRE that water
in such quantities, and of potentially potable quality, constitutes a
strategic asset in an area of Kent where water resources are already under
stress and where the imbalance between supply and demand is expected to
increase still further with the growth in domestic consumption forecast to
accompany housing development under the South East Plan. If anything, this
will be further exacerbated by the impact of climate change and the imposition
of increasingly stringent standards for the protection of river and wetland
habitats. The delicate balance of resources, in east Kent in particular, is
evidenced by the recent decision by Folkestone and Dover Water Services to
seek formal "water scarcity" status as a basis for implementing
universal domestic metering throughout its supply area. The 2003 Annual Report
of the South East Water Resources Forum ( SEEDA / Environment Agency) ( Ref.
I) includes a statement under the heading "Pressures on Water Resources
in the South East" that "there is already a shortage of water in the
south and east of England and many water companies are operating with large or
significant deficits in their supply / demand balance".
3.3 The pressure on the resources of
the Great Stour have been highlighted by the Environment Agency ( EA)
following their assessment of the river and its associated groundwater,
carried out as part of the Catchment Abstraction Management Strategy published
in May 2003 ( Ref. 2 ) .They have concluded that resources are already
over-committed, mainly as a consequence of the high levels of abstraction from
the underlying chalk aquifer which also serves as the principal source of
spring flow to the river. Future investigations are planned, aimed at
evaluating the scope for reducing abstraction from the catchment above the
Little Stour confluence in order to improve the base flow regime of the main
river. In light of this it is perhaps surprising that SWS, in formulating
their scheme options, gave no consideration to the potential of the
Weatherlees discharge as a means of augmenting flows in the lower reaches of
the river. It appears to have been discounted on "environmental"
grounds but no details are provided as to their nature or significance.
3.4 Seen in this context, the scheme,
as proposed, represents a lost opportunity to make-good at least part of the
resource deficit. It is also at odds with the declared commitment to the
sustainable re-use of wastewater and, furthermore, may seem even more perverse
in light of the "twin track" approach to the management of water
resources as promoted by the Agency and SEEDA in the 2003 report. This
incorporates development options such as the construction or enlargement of
supply reservoirs ( e.g. Bewl Water ), inter-catchment transfers and
desalination; all this alongside water- efficiency measures formulated to
reduce demand-side wastage. The following examples of policy statements
made public by SWS and EA in recent years would seem to confirm a
general commitment to the re-use of wastewater as a component of the regional
resource management strategy .
i) Environment
Agency. Southern Region Water Resources Strategy: Implementation Plan.
September 2002 ( Ref 3 )
Table 2 identifies an objective of
investigating and sustaining "the potential for re-use of wastewater
currently discharged to coastal waters". This is listed elsewhere in
the same document as a "specific task" ( topic 8.3) to review
current and planned effluent discharge arrangements, standards and coastal
discharges, and "re-use options and needs". The project was
scheduled to commence in April 2002 with "significant progress"
required by December 2004.
ii) Environment
Agency. Stour Catchment Abstraction Management Strategy. May 2003.
Para 5.5, summarising actions by
the Agency, includes, as a current activity , the development of a proposal
"to review the potential re-use of effluent currently discharged to
coastal waters". This is developed further in Table 5 as project No 14
to "Investigate the potential of re-use of wastewater treatment works
effluent as a facility for enhancing the freshwater component of the upper
Stour estuary".
iii) South
East Water Resources Forum ( SEEDA / EA ). Annual Reuort 2003 ( Ref 2 }
Page 21 of the document comprises a
listing of key points for sustainable development of S.E. river catchments.
They include :-
- identification of the Kentish
Stour as a priority catchment for investigation,
- the acute pressures on water
resources in S.E. Region, and,
- the importance of integrated
catchment management.
Page 35 summarises key points by
SWS under the heading "Water supply and sewerage -a water company
perspective". The list includes a reference to the "scope for
re-use of treated wastewater that is currently discharged directly to the
sea".
3.5 The question arises as to exactly
how much progress has been made by SWS and EA toward the objective of
assessing the practicability of the re-use option. For this, the EA will
presumably be able to draw on their own experience as the consenting authority
in the Langford effluent recycling scheme ( Ref. 4 ) which is the culmination
of 10 years research and development by Essex and Suffolk Water and is now a
fully operational public supply facility with a capacity of 40M1/d using
treated wastewater fully compliant with U .K and
European water supply and environmental standards. The discharge consent (
Ref. 5 ) issued by EA in April 2000 incorporates schedules relating to
secondary treated sewage effluent in accordance with Urban Waste Water
Treatment Regulations, and includes provisions for removal of phosphates,
nitrates, ammonia, oestrogens and specified pathogens. The River Chelmer, the
receiving water for the consented discharge, has an annual average flow at
Langford of 220 Ml/d. This includes an existing 11% of effluent loading from
other sources, and, with the additional maximum daily discharge of 40 Ml/d (
dwf of 30 Ml/d), this would give a total loading of 25% ( Ref. 6 ).
No corresponding direct measurements of flow are available
for the Stour at Weatherlees but the long term record for the gauging station
at Horton, upstream of Canterbury, gives a figure of270 M1/d for the annual
average. Allowing for tributary inflow and a proportion of treated effluent
entering the intervening reaches of the river between Canterbury and
Weatherlees, the discharge from the treatment works would probably amount to
an additional concentration of not more than 10%.
4. CONCLUSIONS AND RECOMMENDATIONS
4.1. To judge from the Langford scheme, the technology now
exists for treating waste-water to the highest environmental and drinking
water standards under U .K and European law. There would therefore seem to be
neither need nor justification for the scheme as presented by SWS in
Application No 3. In particular, we would welcome the opinion of EA as to
whether there would be any reason, at least at first sight, as to why a
treatment and re-use facility on the lines of the Langford model could not be
successfully incorporated in the Weatherlees extension. Much, if not all, of
the essential groundwork appears to have been completed by Essex and Suffolk,
and the necessary additional conversion works would, presumably, not add
significantly to the programme.
4.2
i) We therefore strongly recommend that provision for a return pipeline be
deleted from Application No 3 and that a new application be submitted for
discharge of treated effluent to the river at an appropriate distance upstream
of the existing works.
ii) We also recommend that SWS be directed to engage with EA
in the formulation of a strategy for the sustainable re-use of the Margate /
Broadstairs wastewater; with special attention given to the potential for
addressing peak demand growth in the Thanet Area. Consideration should also be
given to the scope for using part of this resource for augmenting summer-
period flows in the River Stour.
GDW.
16.08.2004.
REFERENCES.
- South East Water Resources Forum, Annual Report 2003, Page
35; "Water Supply and Sewerage -A Water Company Perspective".
- The Stour Catchment Abstraction Management Strategy;
Environment Agency, May 2003.
- Water resources for the future, A strategy for Southern
Region; Implementation Plan, Environment Agency, September 2002.
- Langford Recycling Scheme; Developing new water resources,
Essex and Suffolk Water information sheet. ( www.eswater.co.uk ).
- Water Resources Act 1991 Schedule 10 Consent to Discharge (
No PRENF / 11530 ). Issued by Environment Agency to Essex and Suffolk Water,
20th Apri12000.
- Walker,D. The Promotion of a Planned Indirect Wastewater
Re-use Scheme in Essex. J. Ch. Instn Water and Environmental Management
November 2001.
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