Hydrobiologia 395/396: 411–417, 1999.D.M. Harper, B. Brierley, A.J.D. Ferguson & G. Phillips (eds), The Ecological Bases for Lake and Reservoir Management.© 1999Kluwer Academic Publishers. Printed in the Netherlands.

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A strategy for managing still waters in the United Kingdom

Mark EverardThe Natural Step UK, 9 Imperial Square, Cheltenham, Gloucestershire GL50 1QB, U.K.

Key words:still waters, ponds, conservation, management

Abstract

The ecological and amenity values of fresh still waters do not depend primarily upon the size or permanence ofthe water body. The ecological importance of still waters may be recognised by global, European, national or locallegislation or agreements. However, non-designated still waters may also be of great importance, both to their localhuman population and through their contribution to ecological processes. In particular, small still waters, whilstindividually of low importance at the national scale, may nevertheless have a disproportionately high ecologicaland/or cultural value at the local scale. The uses to which we put our still water resources, and the land within theirupstream catchments, exert pressure on both ecological and utility values. Historically, still-water protection hasbeen addressed on a reactive basis. Although a considerable, and largely under-utilised, armoury of powers exist fortheir protection, resource limitations place real constraints upon the effort that regulatory Authorities can expendupon still waters. Broader public awareness and ownership of the key issues and values, and of the underpinninglegislation, must therefore form part of protective strategies for the future. The Environment Agency has a key roleto play in this education process, which may represent a cost-effective means for it to discharge its responsibilitiesto the water environment.

Introduction

The diverse geomorphology and predominantly wetatlantic climate of the United Kingdom gives rise toan abundance of fresh water bodies. In England andWales, the natural still water resource is augmentedby significant numbers of man-made water bodies ofmany types.

At a global scale, the still waters of England andWales are relatively small. There is also a marked re-gional variation in opinion across the country as tohow big a still water must be to quality as a lake(Mockerkin Tarn and Red Tarn in Cumbria, though notqualifying by local definition as lakes, are appreciablybigger than the Heath Lake SSSI in the drier southerncounty of Berkshire). The distinction between lakesand reservoirs is equally vague; some natural lakesserve as a source for potable supply, many man-madestill waters are not utilised as sources for water ab-straction, whereas lakes such as Cumbria’s SeathwaiteTarn are in fact natural lakes enlarged by dams toserve as a source of drinking water. In this paper, thenational resource of still waters is considered as a con-tinuum, avoiding unhelpful distinctions between lakes,reservoirs, tarns and ponds.

The ecological processes and utility values per-formed by these still water bodies are diverse, as arethe threats that they face. The purpose of this chapteris to examine the reasons why we should pay atten-tion to the needs of our still water resource, and torecommend an affordable strategy for its future man-agement. This will be addressed in three parts: anoverview of our still water resource; a summary ofpriorities accorded to still waters in recent years; andrecommendations for the future.

The still water resource of England and Wales

The question we must first address in considering themanagement of our still waters is the quantity andnature of the present resource, the trends observedin this resource, its importance to nature and to thehuman population, and the threats it faces.

The extent of the resource

Johnes et al. (1994) estimate that there are some 1,700fresh still water bodies with an area of 4 hectares ormore in England and Wales, 12,500 of 2 hectares or

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more, and 50,000 of 1 hectare or more. Through-out this century, there has been a net increase inthe numbers of large still waters due to the creationof reservoirs, mineral extraction pits (predominantlyclay, gravel, sand and peat) and balancing ponds. Inthe Environment Agency’s Thames Region alone, thetwo natural lakes (Frensham Great and Little Pondsnear Godalming, Surrey) represent only a small pro-portion of the still water resource compared to the 25square miles of reservoirs and numerous gravel extrac-tion pits along the Thames Valley (Sweeting, personalcommunication). The net trend in smaller still wa-ters is, however, one of sharp decline. In Britain asa whole, 90% of fresh water bodies are less than 1hectare in area (DoE, 1993). There are probably some400,000 remaining ponds in England and Wales, theremnants of a 65% loss over the last century, with anestimated continuing loss of 1% (around 9000 ponds)per annum (Sansom, 1993).

Very few of these water bodies are truly ‘natural’.Many are modified to some extent from their originalstate; usually enlargement by dams or dredging, al-though groundwater abstraction can affect the waterregime in many water bodies. The larger water bodiesare almost exclusively permanent, although seasonaldrawdown at the lake margins may be ecologicallyimportant. However, a large number of smaller waterbodies are temporary, drying on a seasonal basis orduring extended dry periods.

Scales of importance

Our still waters are important at a range of scales fromthe global to the local.

At the global scale, a significant number are des-ignated as RAMSAR sites, or may otherwise make asignificant contribution to the maintenance of biod-iversity (The UK became a signatory of the Biod-iversity Convention at the ‘Earth Summit’, Rio deJaniero, in 1992.)

At theEuropean scale, a large number of still wa-ters are contained within designations under variousEC/EU Directives including:

• SACs (Special Areas for Conservation) under theEC Habitats Directive (CEC, 1992).

• SPAs (Special Protection Areas) under the ECBirds Directive (CEC, 1979).

• SA[E]s (Sensitive Areas [Eutrophic]) under theEC Urban Waste Water Treatment Directive (CEC,1991a).

• NVZs (Nitrate Vulnerable Zones) under the ECNitrates Directive (CEC, 1991b).• Stretches or areas designated as fisheries under the

EC Freshwater Fish Directive (CEC, 1978).• Abstraction points designated under the EC Sur-

face Water Abstraction Directive (CEC, 1975).In addition, the EC Bathing Waters Directive

(CEC, 1976) does not preclude the designation offreshwater bathing beaches (there are many instancesin continental Europe), although the UK Govern-ment has chosen not to designate any such freshwaterbeaches. The proposed EU Directive on the Ecolo-gical Quality of Surface Waters, and the prospectivewetland directive that may stem from the recent ECCommunication on Wetlands (EC, 1995) may alsorelate to the still fresh waters of England and Wales.

At thenational scale, various still fresh waters fallwithin, or are either partially or wholly covered by,designated NNRs (National Nature Reserves) or SSSIs(Sites of Special Scientific Interest) under the Wildlifeand Countryside Act 1981, or its predecessor 1949Act. Still waters form a significant component of theecological and landscape interest of various NationalParks, most significantly the Broads of East Angliaand the Lake District of Cumbria, as well as of AONBs(Areas of Outstanding Natural Beauty) throughoutthe country. Mesotrophic lakes, and wetland habitatsskirting lakes of all types, are noted as of particularecological value inBiodiversity: The UK Action Plan(DoE, 1994), and many other types of still waters maybe important habitats for species scheduled in the Plan.

At the local scale, smaller still waters are fre-quently important features of LNRs (Local NatureReserves), and may also be important components ofsites of heritage value (for example, the famous con-cert venue at Kenwood House in North London, orthe Estate Lakes of Blenheim Palace and other suchexamples of traditional English landscaping).

The values of still waters

It is important to note that all still waters, whetherdesignated or not under domestic or international le-gislation, or forming part of a high profile site, maynevertheless be of importance for any or all of a widerange of reasons summarised in Table 1. A villagepond, though individually of low importance at thelarger scale, may act as an important focal point forvillage life. In addition, these small water bodiesmay provide an important education resource, providevalued fisheries and leisure opportunities, and act as

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Table 1. The Potential Importance of Still Water Bodies

Ecological values:Habitats of importance to aquatic species

Habitats of importance to migratory species

Source of primary and secondary productivity

Amenity values:Fisheries

Field sports (e.g. wildfowling)

Leisure opportunities

Water sports (e.g. diving, canoeing, swimming,

paddling, etc)

Utility values:Abstraction for potable supply

Provision of water to industry

Provision of water for livestock watering and spray irrigation

Balancing ponds for canal water

Water management values:Balancing ponds and floodwater detention/desynchronisation

Water Quality improvements/waste treatment

Long-term environmental/heritage records:Diatom frustules; chrysophyte scales;

photosynthetic pigments

Pollen grains

Cladoceran and Ostracod carapaces

Chironomid head capsules

Carbonaceous granules from coal-burning

Archaeological remains

Other values:Component of landscape, heritage and

natural beauty

Educational resource

Shellfish farming

important corridors or ‘islands’ for wildlife. Small stillwaters then, whilst perhaps of low significance indi-vidually at the national scale, nevertheless collectivelyrepresent a highly important and largely overlookednatural resource. As previously observed, this resourceof small still water bodies is inadequately protected.

A surprising number of Red Data Book species(our most endangered species of plants and animals)occur in temporary water bodies (Biggs et al., 1994;Collinson et al., 1995), and Pond Action (1993) con-clude that the wildlife value of ponds is likely to behigh where the surrounding land has been sympathet-

ically managed. The importance of a water body doesnot therefore depend only upon its size or permanence.Even the humble, yet totally artificial, garden pondmay be important for many of the reasons outlinedabove, and may provide important sites for threatenedaquatic species (for example, the great crested newtTriturus cristatus) which feature in Red Data Booksor are scheduled under the Wildlife and CountrysideAct 1981, the EC Habitats Directive (CEC, 1992) orthe UK Biodiversity Action Plan (DoE, 1994).

The current basis for still water management

Greater attention is paid to rivers, as opposed to stillfresh waters, in the UK compared to most other coun-tries in northern Europe. The reasons most commonlygiven for this difference in emphasis are that theBritish still water resource comprises a much higherproportion of smaller water bodies and that the coastprovides for a larger amount of our leisure needs.

A ‘straw poll’ of water quality managers in alleight of its regions revealed that the EnvironmentAgency has generally lacked a cohesive strategy foraddressing the needs of the still waters under its con-trol. Whereas some still waters, and particularly largerwater bodies and those with a higher political pro-file (owing to designations under EC/EU Directivesrelating to human uses, or heritage considerations),were the subject of detailed investigations and/or man-agement plans, or were included in Catchment Man-agement Plans, the consensus amongst the managerspolled was that the Agency dealt with still waters ona largely reactive basis. Where still waters were givenattention, the reason for this attention was generallyrelated to human uses of the water body rather than toinnate ecological values. Despite thisad hocapproach,a range of threats (summarised in Table 2) face our stillwaters and particularly our smaller still water bodies.

Priorities for the future

The challenge for the future is to find cost-effectivemeans of sustaining the nation’s resource of fresh stillwaters, managing them in a way that strikes a balancebetween their ecological needs and the uses to whichwe put them and their upstream catchments. The evid-ence presented above suggests that, as a nation, weare failing in our obligations to protect our resource

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Table 2. Significant Threats to Fresh Still Water Bodies

Organic pollution: Domestic sewage, Agricultural activity, Food processing industries

Eutrophication: Point sources, Diffuse sources

Acidification: Aerial Deposition, Afforestation

Siltation: Land use changes, Deforestation

Drainage/Infilling: Agricultural intensification, Urban development

Dumping: Cheap disposal sites for land-owners, Fly-tipping

Introduction of alien species of plants and animals

Complex pollutants: Organophosphates and other synthetics, Heavy metals, Oestrogenic substances

of small still waters, which may have a dispropor-tionately large cumulative value. In this section, theconstraints under which regulatory authorities operateare considered prior to making final recommenda-tions about future priorities for action to protect theecological and utility values of our still waters.

Resource constraints

Regulatory authorities by necessity operate under fin-ancial and human resource constraints. This factoralone is sufficient to explain why focus has been givento so few of our water bodies. Resource constraintsrequire us to limit ourselves to larger and higher pro-file lakes, and one has to weigh up the desirabilityof increasing this level of investment against othernational priorities such as the provision of hospitalbeds or educational services. Assuming 200 workingdays per person per year, and an average of four stillwaters per working day, it would take in excess of560 person years of resource per annum to visit eachof our 450 000 still water bodies just once per year.(This figure will be an under-estimate due to periodicunsuitable weather conditions.) A single visit in anyone year would be inadequate to take account of theconsiderable spatial and temporal variation that occurswithin a still water body, and so would not represent acost-effective deployment of the substantial amount ofhuman resource.

Although the National Rivers Authority before andthe Environment Agency now have invested signific-

antly in technology that may ultimately provide a morecost-effective means of assessing still waters (remotesensing, test kits, biomarkers, etc), these technolo-gies are as yet immature or under used. Technologyalone can not necessarily be relied upon to surmountthe substantial resource constraint, which is currentlyin shortfall by some three orders of magnitude, werewe to need to deal with every still water. The is-sue then is not to demand ever more funding but,particularly in the light of the new duty upon the Envir-onment Agency to have regard for costs and benefits,to find more efficient ways of utilising our availableresources.

Legal constraints

The existing legal framework under which regulat-ory authorities operate in England and Wales providesus with a range of powers and duties, in addition tosome conspicuous oversights. The legislation avail-able to the Environment Agency can be broken downinto three major categories: legislation inherited fromconstituent organisations; new legislation introducedby the Environment Act 1995; and other strands oflegislation that provide the Agency with additionalpowers.

The legislation inherited from constituent organ-isations (NRA, Her Majesty’s Inspectorate of Pollu-tion, and the Waste Regulation Authorities) has beenrolled forward into the Environment Agency and con-solidated under the Environment Act 1995. Although

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strands of former HMIP powers are directly relevant incontrolling acidic aerial deposition and the dischargeof dangerous substances to water, the bulk of powersand duties relating to the water environment are inher-ited from the NRA through consolidation of the WaterResources Act 1991. Most of the powers and dutiescontained in the Water Resources Act are limited to‘Controlled Waters’, a definition from which still wa-ter bodies that are not connected directly to surfacewater streams or to groundwater are excluded. It istherefore precisely those smaller still waters that ap-pear to be most at risk that are excluded from the legalarmoury inherited from the NRA.

Although perhaps not their primary intention, vari-ous pieces of new legislation introduced by the Envir-onment Act 1995 may add considerably to the powersof the Agency to deal with matters affecting our stillwaters. These new pieces of legislation include:

• Section 4 of the Act introduces a new ‘umbrella’duty to the achievement of sustainable develop-ment. Sustainability relates to the protection ofboth ecological and societal values, and the protec-tion of biological and heritage resources thereforeform central aspects of the duty. It is reasonableto presume that the Agency will target its ef-forts to deliver the maximum benefits to the waterenvironment.

• The new requirement under Section 5(2)(b) of theAct to "...form an opinion of the state of pollutionof the environment..." of England and Wales existswithout reference to any particular legal restric-tions, and so the Agency is therefore at liberty tooffer objective opinions of the state of our nationalfreshwater resource and upon the actions that maybe required to safeguard and/or restore it.

• The Agency is required to take account of the costsand benefits of its decisions. Given the unfortunatetrend in loss of small still waters, and their dispro-portionately large ecological and societal values,it is possible that the greatest ecological and soci-etal benefits per unit investment may be achievedby targeting these largely neglected water bodies.It is also incumbent upon the Agency to investig-ate innovative and cost-effective means to betterutilise its limited resources to deliver the bestvalue-for-money.

• Under arrangements with local authorities, healthand safety registers of manmade still watersgreater than 25,000m2 will transfer across to theAgency in due course, giving the Agency new

powers to control aspects of these still water bod-ies.

The United Kingdom has made various other com-mitments to ecological protection, which provideadditional powers for regulatory authorities. Theseinclude:• The UK Biodiversity Action Plan, produced in

compliance with the requirements of the Biod-iversity Convention.• The Conservation (Natural Habitats etc) Regula-

tions 1994, which require all regulatory authoritiesto use their powers to promote nature conservationin SACs designated under the EC Habitats Direct-ive (CEC 1992) and SPAs designated under the ECBirds Directive (CEC 1979).• TheConvention on Wetlands of International Im-

portance Especially as Waterfowl Habitat(The"Ramsar Convention"), which aims to stem pro-gressive encroachment on and loss of wetlands,and ratified by the UK in 1976. Under the terms ofthe convention, the definition of wetlands includesfresh and saline waters up to a depth of 6 metres(i.e. including most of the smaller still waters andmuch of the littoral zone of many of our larger wa-ter bodies), and signatories are required to developa national strategy for their protection. The UKhas not to date developed such a strategy, however,the Ramsar Commission has recently recognisedthat Water Management will be a crucial issuein the 21st century. Although not directly provid-ing additional powers to the Agency, the RamsarConvention provides additional justification forundertaking actions affecting aquatic systems.As part of its ongoing activities, it is necessary for

the Agency to influence partner organisations to usethe powers and duties at their disposal to provide pro-tection for the freshwater environment. These partnersinclude both statutory agencies (Ministry of Agricul-ture, Fisheries and Food, English Nature, CountrysideCouncil for Wales, etc) as well as Non-GovernmentalOrganisations (e.g. Royal Society for the Protection ofBirds, Wildfowl and Wetlands Trust). In addition, theAgency seeks to influence land owners and land usersaccording to best practice.

In concluding this subsection on legal constraints,it is worth noting that the legislation available toprotect small still water bodies is weak. Prior notific-ation to Local Authorities is required before buildinga pond, other than a garden pond, and planning per-mission may be required if the pond is put to non-agricultural uses and is within 25 m of a classified

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road or is created by exporting soil or gravel fromthe site. However, no such notification and permis-sion is required for filling in a pond. In the light bothof the declining trend and the Government’s commit-ments to maintaining biodiversity, this omission in thelegislation is in urgent need of review.

Knowledge constraints

The conference and these proceedings have gone along way towards bringing together the state of theart in current understanding of lake and reservoirmanagement. The Environment Agency also has aprogramme of continuing research including particip-ation in the 1996–8 Pond Survey (joint funding withDoE); a project on lake classification and monitoring(linked to a closely-related sediment profiling studyfunded by English Nature); continued development oflake eutrophication models; and studies on novel tech-niques for the biological assessment of still waters. Inaddition to its own programme of research, the En-vironment Agency also participates in research led bypartner organisations.

A body of research into the functional analysis ofwetland (e.g. Maltby, 1991; Dugan, 1993; Maltby etal., 1994) and riverine (Harper et al., 1992; 1995)systems has been steadily growing over the past dec-ade. The essence of functional analysis is to determ-ine, where possible on a semi-quantitative basis, theprocessesthat habitat features perform within ecosys-tems. In aquatic systems, these processes are hydro-logical (for example, desynchronisation and detentionof floodwater), physico–chemical (for example, nu-trient stripping, settlement of suspended matter, etc),ecological (for example, primary productivity or pro-vision of diverse habitats), and heritage (for example,the preservation of archaeological remains). In recentyears, various workers have sought to link functionalanalysis with environmental economics (e.g. Denny,1994; Everard, 1998a,b) as a justification to protect,restore or recreate wetland habitats, and to integrateconservation and management. It is probable that theextension of functional analysis techniques to stillwaters will provide a fruitful line of research.

Environment Agency policy should be led by thebest available science. However, having briefly con-sidered present and potential future lines of investig-ation, and acknowledged that better scientific under-standing will always improve management decisions,the clear trends outlined previously in this paper sug-gest that lack of knowledge is not one of the major

constraints to action. In light of the serious decline ofour smaller still waters, lack of knowledge should notbe used as an excuse for lack of action.

A recommended strategy for the management of stillwater bodies

Whilst it may be desirable to include all of our stillwaters in Catchment Management Plans (or their suc-cessor Local Environment Agency Plans), or to for-mulate Action Plans or utilise elegant models suchas those addressed elsewhere in this book, to addresstheir specific needs, we must also acknowledge theresource constraints under which we operate. For thisreason, the present focus of intensive activity on just afew larger and/or high profile water bodies is unlikelyto change in the foreseeable future. Nor is it likelythat technological breakthroughs will significantly en-hance our ability to deal with the key issues. It ishoped that, through consultation on Catchment Man-agement Plans/Local Environment Agency Plans), theconcerned public and external organisations can no-tify us of perceived problems in additional still waters,which we can then prioritise for detailed study andaction.

What then of the remainder of the 450,000 wa-ter bodies that fall outside of this safety net? Fromthe above discussion, it is apparent that, althoughindividually they may be of low significance at thenational scale, our smaller still waters collectively rep-resent a highly valuable resource, the needs of whichare only poorly considered or recognised in existinglegislation. This situation begs two questions:• Financially, can we afford to consider them?• Ecologically, can we affordnot to consider them?

There is an innate tension between these two ques-tions, and it is unlikely that Government will increasepublic expenditure on our still waters in the face ofother national priorities. It is therefore up to the Envir-onment Agency, and particularly in the light of its newduties, to investigate innovative, cost-effective meth-ods to better account for the needs of the nation’s stillwater resources.

Promotion of a wider public ownership of the prob-lems is one of the options available to the Agency tomaximise its effect per unit investment. This recom-mendation is not offered merely as a platitude; ratherit recognises that the Agency has a central pro-activerole to play in promoting wider awareness and own-ership of problems of common concern. The terms ofthis pro-active role may include:

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• Promoting a wider awareness of the importanceand values of still waters (for example, throughRSNC or the schools national curriculum, definingthe role of still water protection within Agenda 21,liaison with the media for public education, etc),ensuring that the relevant information is presentedin a form comprehensible to a form comprehens-ible to and usable by the general public.• Notifying partner organisations of particular prob-

lems observed during routine Agency investigativework.• Promoting a wider awareness of the powers avail-

able to the Agency, to its partners and to thewider public to utilise for the purpose of still waterprotection.• Targeted support, both technical and financial, for

specific projects.• Applying pressure upon Government to close

loopholes in the law such as those preventing theloss of ponds and to comply with the requirementsof the Ramsar Convention.Public awareness and ownership of problems are

frequently cited as being central to sustainable solu-tions. This principle is clearly applicable to the pro-tection of our diverse national still water resource.The Environment Agency has a key role to play inthe protection of natural resources, yet protection ofthese resources frequently relies upon action by thoseover which we have no direct regulatory powers. Act-ive promotion of public participation and ownershipof problems affecting still waters by the Agency maytherefore not only represent a cost-effective and in-novative solution, but would appear to offer the bestprospect for sustained protection.

Acknowledgements

The author wishes to thank the conference organisersfor inviting this contribution to the proceedings, andfor the production of a ‘state of the art’ volume on theecological management of lakes and reservoirs. Theopinions expressed here are the author’s own and donot necessarily represent any official view.

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