River RestorationRiver Restoration– Danish experience and examples

National Environmental Research Institute

River Restoration– Danish experience and examples

Editor: Hans Ole Hansen

Department of Streams and Riparian Areas

Ministry of Environment and Energy

National Environmental Research Institute

1996

River Restoration– Danish experience and examples

Editor: Hans Ole Hansen

Ministry of Environment and EnergyNational Environmental Research Institute

1996

River Restoration– Danish experience and examples

Editor:Hans Ole Hansen,Department of Streams and Riparian Areas

Published by:National Environmental Research Institute©,Denmark

Publication year:September 1996

Translation:David I. Barry, On Line Activities

Layout:Kathe Møgelvang and Juana Jacobsen

Cover picture:J.W. Luftfoto and Sønderjylland County

Printed by:Silkeborg Bogtryk

ISBN: 87–7772–279–5

Impression: 600

Price: DKK 150 (incl. 25% VAT, excl. postage)

For sale at:National Environmental Research InstituteVejlsøvej 25, P.O. Box 314DK–8600 Silkeborg, DenmarkTlf. +45 89 201 400 – Fax +45 89 201 414

MiljøbutikkenInformation and BooksLæderstræde 1DK–1201 Copenhagen K, DenmarkTel.: +45 33 379 292 (Books)Tel.: +45 33 927 692 (Information)

3

1233.13.23.33.43.53.63.73.83.93.103.113.123.133.143.153.163.173.183.193.203.213.223.233.24

45

Introduction 5

From idea to reality 13

Completed watercourse rehabilitation projects 21

Tøsbæk/Spånbæk brook at Dybvad 22Pump station at Gjøl 24Lerkenfeld stream at Østrup 26River Storå at Holstebro 28Idom stream at Idum 30Rind stream at Herning 32River Gudenå at Langå 35Lilleå stream at Hadsten 37Lammebæk brook at Daugård 39Kvak Møllebæk brook at Skibet 41River Brede at Løgumkloster 43River Brede at Bredebro 46River Odense at Ejby Mølle, Odense 48River Odense at The Seahorse, Odense 50Lindved stream at Hollufgård, Odense 52Holmehave brook at Borreby Mill, Odense 55Esrum stream at lake Esrum 58Græse stream at Frederikssund 60Store Vejleå stream near Glostrup 62Køge stream at Lellinge 64Køge stream at Bjæverskov 66River Suså at Holløse Mill, Skelby 68Lilleå stream at Kongsted 70

Søbæk brook at Neksø 72

Classification system for watercourse rehabilitation 73

Environmental impact of watercourse rehabilitation 80

Appendix A 91

References 98

Contents

5

1Hans Ole HansenBent Lauge Madsen

There are approximately 30,000 km ofwatercourse of natural origin in Denmark,and an equivalent length of man-madewatercourses. This should provide goodopportunities to enjoy nature, as well as amultitude of habitats for a diverse floraand fauna.

However, during the course of thiscentury the majority of our watercourseshave been channelized to drain agriculturalland, freshwater fish farms, industry andurban areas. Channelization was oftenaccompanied by the construction of weirsand other obstructions, and in manycases these effectively hindered the freepassage of fish and stream macroinverte-brates. As a result, there are now onlyfew watercourses that live up to our ideasof a natural watercourse. The situation isstarting to improve, though, partly as aresult of changes and improvements inthe administration of our watercourses.

Danish watercourseadministrationThe two main laws governing Danishwatercourses are the Watercourse Actand the Environmental Protection Act.From the administrative point of view,Danish watercourses are divided intothree groups: County watercourses,municipal watercourses and privatewatercourses. The County is the water-course authority in the case of countywatercourses, while the Municipality isthe watercourse authority for bothmunicipal and private watercourses. Thewatercourse authority’s task is to ensurecompliance with the provisions of the

Watercourse Act, for example withrespect to watercourse maintenance.

Watercourse environmental qualityobjectivesThe original Danish EnvironmentalProtection Act from 1974 encompassed aplanning system that in the case ofwatercourses, was implemented in theform of a system of specific qualityobjectives, a system that has played, andstill plays, a crucial role in endeavours tosafeguard watercourse environmentalquality (Box 1.1). The environmentalquality objective for each watercourse isset forth in the County Plan. In settingthe objectives, the County takes intoaccount the natural state of the water-course, what impact man has had, theintended use of the watercourse, andwhat can realistically be achieved.Through this system of quality objectivesit has been possible to differentiatebetween different watercourses andconcentrate efforts where they are ofgreatest benefit.

Pollutional state of DanishwatercoursesThe County has supervisory responsibilityfor the pollutional state of all water-courses. Pollutional state is evaluated byinvestigating the macroinvertebrate faunainhabiting the watercourse, and is ratedon a scale from I to IV. I corresponds to awatercourse with a very varied macro-invertebrate fauna while IV correspondsto one with a very uniform or absentfauna. The national streampollutionmonitoring network comprises 220

Introduction

6

stations where pollutional state ismonitored annually. In addition, though,the individual county authorities monitorpollutional state less frequently at manyhundreds of additional stations.

Action Plan on the AquaticEnvironmentIn 1987, the Danish government passed anew Action Plan on the Aquatic Environ-ment aimed at considerably reducingnutrient and organic matter loading ofthe aquatic environment. Since adoptionof the Action Plan, the quality of thewater in our watercourses has improvedyear by year, largely due to the upgradingof sewage works. However, clean wateralone is not sufficient to ensure satisfac-tory watercourse quality. If the water-course lacks physical variation, habitatsfor the flora and fauna will be limited innumber and quality. At the same time,poor physical conditions often have anegative impact on water quality becauseoxygenation and self-purification will beless effective. Similarly, drainage ofriparian areas can also have a negative

effect on water quality due to increasedloading with ochre, etc.

Restoration or rehabilitationConsiderable work still needs to be doneto improve the physical condition of ourwatercourses if watercourse quality is tomatch up to the increasingly good qualityrequirements stipulated for stream water.This can be achieved through environ-mentally sound watercourse maintenanceas well as through various types ofrestoration measure. Since these twoapproaches are usually combined withthe general objective of improving thephysical condition of our watercourses, itis useful to use a term that encompassesboth environmentally sound maintenanceand restoration measures.

In this book, we have chosen to usethe term watercourse rehabilitation, aterm gaining increasing acceptance in thescientific community. When the measureused only involves a change in thephysical condition of the watercourse(excavation, etc.), we use the termwatercourse restoration.

15 years’ experienceWith the advent of the new WatercourseAct some 15 years ago, it became legallypermissible to rehabilitate Danish water-courses. This possibility has been ex-ploited, and over the years, numerousrehabilitation projects have been carriedout – ranging from the laying out ofspawning gravel to major projects aimedat remeandering watercourses andimproving the interplay between water-courses and their river valley.

However, rehabilitation projects areseldom followed up by studies of theimpact of restoration on biological,chemical and physical conditions in thewatercourses and their riparian areas.Similarly, the experience gained from theindividual projects is seldom published,and hence is seldom of benefit to othersworking with watercourse rehabilitation.There is therefore a need to describe the

various types of rehabilitation project andmethods, and to evaluate their impact.

In 1994, the Danish EnvironmentalProtection Agency, the NationalEnvironmental Research Institute and the14 Danish Counties therefore initiatedthe project “Watercourse restoration –Methods and effects”. The main aim ofthe project was to collect and collateexisting knowledge on restorationmethods and their effects. The presentbook, which is partly built up aroundexamples from the counties, is the firstresult of this project.

A further aim of the project was todescribe the physical conditions requiredby the fish inhabiting our watercourses.Fish are a good indicator of watercoursequality, and an understanding of theirrequirements is an important tool whenplanning restoration or changing main-tenance practice. If conditions are goodfor fish, they are usually also good forstream macroinvertebrates and plants.The results of this part of the project havebeen published as a report describing theconditions required by all Danishfreshwater fish (1).

The European Centre forRiver Restoration (ECRR)Since the first international conference in1991 in Lund, Sweden (2), on riverrestoration there has been an increasingEuropean interest in restoring water-courses and river valley ecosystems forthe benefit of wildlife. At the same time,there is increasing awareness thatreinstating naturally functioning water-course-river valley systems also yieldscatchment management benefits,particularly by increasing flood waterstorage capacity, enhancing nutrientretention and ameliorating low discharge.Sustainable management and restorationof watercourses and river valley ecosys-tems may also reduce river maintenancecosts and provide better amenity andrecreational facilities.

The environmental quality objective for each Danishwatercourse is set forth in the County Plan. TheCounty Council can choose between a variety ofenvironmental quality objectives, or they can formu-late their own objectives. In principle, there are threegroups of watercourse quality objectives: Stringent(A), basic (B) and eased (C, D, E, F). The objectives areas follows:

A: Areas of special scientific interestB1: Salmonid spawning and nursery watersB2: Salmonid watersB3: Cyprinid watersB4: Watercourses with a varied flora and fauna but

of little value to fishC: Watercourses to be used for drainage purposesD: Watercourses affected by waste waterE: Watercourses affected by water abstractionF: Watercourses affected by ochre

Box 1.1.

Watercourse

environmental

quality objectives.

Introduction

7

Danish regional and nationalauthorities have accumulated considerableexperience and know-how regardingwatercourse and river valley managementand restoration during the last decade,both with respect to legislation, conser-vation and administration, as well as topractical experience in carrying outdifferent management and restorationmeasures in river systems and monitoringof their ecological effects.

Environmentally sustainable manage-ment and restoration of watercourses wasincluded in the Danish Watercourse Actas early as 1982, and in 1987 naturerestoration was introduced as an elementof the 1987 “Strategy on MarginalLands”, the aim of which was to restore20,000 ha of former wetlands. More than1,000 small and larger-scale riverrestoration projects have so far beenundertaken, primarily by the DanishCounties and Municipalities.

The National Environmental ResearchInstitute (NERI) is the national platform inDenmark for monitoring and scientificresearch on watercourse and river valleymanagement and restoration. In Denmarkwatercourse and river valley managementand restoration projects are mainlyundertaken by the Counties andmunicipalities with the support of theDanish Environmental Protection Agencyand the Danish Forestry and NatureAgency. NERI collaborates with the localand central authorities on the collectionof information on watercourse and rivervalley management and restoration andthe dissemination of the experiencegained through newsletters, workshops,training courses, technical handbooks,videos, etc.

In 1993, the EU Life Programmegranted funds to establish a majorEuropean Demonstration Project inDenmark and the United Kingdom led bythe Sønderjylland County. As part of thisproject the European Centre for RiverRestoration (ECRR) was established atNERI in Silkeborg in 1995.

NERI is a sectorial research instituteunder the Danish Ministry of Environmentand Energy and is the Danish NationalFocal Point for the European EnvironmentAgency (EEA). In addition, NERIdepartments currently participate in threeEuropean Topic Centres, undertakingprojects for the EEA in international foraconcerning monitoring, establishment ofdatabases, etc. NERI currently has around450 members of staff, as well as 30 PhDstudents and 56 MSc students.

The main aims of the ECRR are topromote sustainable watercourse andriver valley management and restorationmeasures and ensure widespread take-upand dissemination of related manage-ment and restoration activities. TheCentre focuses on establishing a state-of-the-art information base on watercoursemanagement and restoration of naturalhabitats in damaged watercourses andtheir river valleys. This will be achievedusing experience gathered in the Euro-pean Countries concerning watercoursemanagement and restoration conceptsand methodology, as well as on theplanning, execution and impactmonitoring of restoration projects.

The aims of the ECRR will be achievedthrough developing a European Networkof relevant national institutions (Figure 1.1).The Centre and the European RiverRestoration Network will collaborate onensuring the collection and assessment ofexperience and knowledge obtainedthroughout Europe on watercourse and

river valley management and restoration,as well as the dissemination of theinformation to the European audiencethrough newsletters, conferences,workshops, technical handbooks, videos,etc. In addition, the ECRR and theNetwork will promote watercourse andriver valley management and restorationthrough the initiation of DemonstrationProjects in each European country. Theseactivities will ensure that knowledge onriver and river valley management andrestoration will be communicated to thewidest possible European audience forthe benefits of Nature and Society.

The present volume is the ECRR’s firsthandbook and is intended to demonstrateto the European audience the experienceaccumulated in Denmark on watercourseand river valley management andrestoration. For further information youare welcome to contact the ECRR inSilkeborg. The Centre can demonstrateDanish experience via posters and videosand can arrange for tours to Demonstra-tion Project sites in various parts ofDenmark.

The ECRR’s address and telephonenumber is as follows:

European Centre for River RestorationNational Environmental Research InstituteVejlsøvej 25, P.O.Box 314DK-8600 Silkeborg, Denmark

Tel. +45 89 201 400Fax. +45 89 201 414e-mail ECRR@dmu.dk

Basis for watercourserehabilitationWatercourse rehabilitation is purposefulimprovement of the physical and ecologi-cal condition of watercourses. It is a rapidand direct means of achieving theimprovements one would like to see takeplace in watercourses, and in some cases

Figure 1.1.

The European

Centre for River

Restoration and the

European River

Restoration

Network.

Introduction

European Centre for River Restoration

National Network

ECRR

NERIDenmark

European Network

8

Watercourse Act of June 9, 1982

PART 8Restoration of watercourses

37.— (1) In the case of public watercourses whose condi-tion does not fulfil the regional water quality objectives,the watercourse authorities are empowered to improveconditions by means of the following measures:

(a) the establishment of artificial overhanging banks,(b) the laying out of large rocks,(c) the laying out of logs and the like on the

watercourse bed,(d) the establishment of current concentrators and(e) the establishment of spawning grounds.

(2) The watercourse authorities defray the expenses ofrestoration.

(3) The Environmental Protection Agency can subsidizelarger restoration projects.

(4) Anyone sustaining a loss as a result of a restorationproject has the right to compensation.

(5) The Minister for the Environment lays down morespecific regulations concerning restoration projects,including regulations concerning the cooperationbetween water authorities and between watercourseauthorities and other authorities, as well as on theinvolvement of the public.

PART 6Regulation of watercourses

16. Regulation of a watercourse is here taken to meanchanging the physical characteristics of the watercourse,including its course, its width, the height of its bed withrespect to Danish Zero Level and its slope, with the excep-tion of measures encompassed by Parts 8 or 10.

17. Watercourses may only be regulated pursuant to thestipulations of the watercourse authority.

Act of June 14, 1995 amendingthe Watercourse Act

37 a.—(1) In watercourses wheresluices are highly detrimental towatercourse quality, the CountyCouncil can decide pursuant to theprovisions of this Act to implementwhatever measures are necessary torestore satisfactory environmentalquality, including regulating thewatercourse.(2) Measures pursuant to subsection (1)

may not be implemented if to doso disregards significant historicalinterests.

(3) The provisions of Sections 3 (1.1),3 (2) and 3 (3) of the NatureProtection Act do not apply tomeasures implemented by theCounty Council pursuant tosubsection (1).

(4) The Environmental ProtectionAgency can subsidize the implementation of measuresencompassed by subsection (1).

is the only means. In the present spirit ofthings in Denmark, rehabilitation onlyencompasses measures that improve thequality of watercourses as naturalecosystems or as angling waters. Thespecific aim of rehabilitation can be tochange the watercourse’s appearance, tocreate habitats for the fauna and flora, torestore free passage or to improve thewatercourse’s self-purification properties.

Rehabilitation (restoration) wasincorporated in the new DanishWatercourse Act in 1982. The individualmeasures are described as five simplemethods (Box 1.2) – methods that topresent Danish eyes provide extremelylimited possibilities to rehabilitatewatercourses. That they are so limited ispartly due to the misgivings with whichthe restoration concept was received by“drainage interests” at the time the Actwas being drawn up, especially by theagricultural sector. Clear information waswanted about what restoration wouldmean for the watercourse of the future.

A further reason is that the inspirationto restore watercourses largely came fromthe USA. In places such as Michigan andWisconsin, efforts had been made toimprove habitats for salmonid fish inshallow watercourses resembling Danishwatercourses (3). The aim of restorationin the USA was – and still is – to furtherimprove fish waters that are already ofgood quality, i.e. to increase thecatchable fish stock. One way of doing sowas to create artificial overhanging banksusing logs that often extended severalmetres into the adjacent terrain. TheseAmerican experiences were the inspira-tion for the wording of the DanishWatercourse Act, and for the first Danishattempts to rehabilitate watercourses.Apart from these first projects, however,we have not been bound by theAmerican examples. Moreover, methodsof the type used in the USA introduceunnatural “hardware” into watercoursesand are considered undesirable in thepresent Danish view of watercourses.

Box 1.2. Provisions

of the Danish

Watercourse Act

pertaining to

restoration and

regulation.

Thus in contrast to this approach,current Danish philosophy instead favoursrehabilitation measures that blend in withthe natural conditions in the watercourseas simply as possible. For example, wenow prefer to restore free passage atdams by means of riffles and bypass

reaches, while as far as possible refrainingfrom building fish ladders. The latter areconsidered too selective as they primarilyfacilitate the passage of strong salmonids,while other fish and macroinvertebratesare unable to pass. In contrast, a riffle orbypass reach can be traversed by all the

Introduction

9

implementation of environmentally soundmaintenance has led to a four-fold increasein the trout population of county water-courses in less than ten years (6) (Figure1.3). Environmentally sound maintenancehas primarily been implemented in thecounty watercourses, and to a lesserextent in the municipal watercourses (7).

Environmentally sound watercoursemaintenanceWatercourse maintenance can be elabo-rated to environmentally sound water-course maintenance. While traditionalmaintenance aims to “repair” thechanges that take place in a watercourse,environmentally sound watercoursemaintenance aims to actively change thewatercourse in order to develop formsthat make it a well-functioning habitat.

Restoration and environmentally soundmaintenance supplement each other.They both improve physical conditions inwatercourses. With environmentallysound maintenance, one can develop anarrow meandering course in achannelized watercourse using the forcesat work within the watercourse. Thesenew meanders primarily lie within thewatercourse’s cross-sectional profile andare usually formed in a process dominatedby deposition in which the aquatic plantsbecome replaced by marsh plants, whicheventually merge with the banks. As arule, the results are clearly apparent in theform of a narrow winding course thatdevelops within the course of three yearsor less.

fish and macroinvertebrate speciesinhabiting the watercourse. In addition,riffles and bypass reaches function as anatural part of the watercourse, and insome cases do so better than upstreamand downstream reaches (4).

Regulation as a rehabilitation measureDespite the fact that the five methodsmentioned in Part 8 of the WatercourseAct (Box 1.2) are extremely limited, inpractice it has nevertheless been possibleto use other and more extensive forms ofrehabilitation. All that was needed was toobtain approval to regulate the water-course under Part 6 of the WatercourseAct (Box 1.2). The watercourse regulationprovisions were originally formulated witha view to easing water drainage throughdeepening, straightening and wideningof the cross-sectional profile. However,rehabilitation also involves changing thephysical form of a watercourse, and fromthe legal point of view is thereforeregulation. It was thus on the basis ofprovisions on watercourse regulation thatNordjylland County undertook the firstreal rehabilitation projects in Denmark in1980.

A 1995 amendment to theWatercourse Act – Section 37a – added anew provision to the Part dealing withrehabilitation (Box 1.2). This provisionenables the County Council to improveconditions in watercourses in whichsummer discharge is poor, for example,immediately downstream of intakes tofreshwater fish farms. In such cases, theCounty could limit the amount of waterdiverted to the fish farm by stipulating aminimum residual discharge in thewatercourse.

MaintenanceIt is not just through physical restorationthat one can improve the condition andform of watercourses. This can also beachieved through watercourse mainte-nance.

Maintenance of Danish watercourseshas traditionally served the sole purposeof holding in check the natural changesthat take place in watercourses so astoensure that the water could drain awaysufficiently effectively. Thus withtraditional maintenance, one removesvegetation in the watercourse and tosome extent on the banks, removes mudand sand deposits, and removes graveland sand. One works against the naturalforces at work in the watercourse, andhas therefore to repeat maintenanceregularly to keep the watercourse in check.

With the advent of the new Water-course Act, traditional maintenance ofwatercourses has in most cases beenreplaced by more environmentally soundmaintenance. With the new practice, oneworks with the natural forces in thewatercourse by limiting weed clearance,by clearing a current channel, and by notdredging outside the watercourse’sstipulated cross-sectional profile. One nolonger removes stones and gravel andone does not clear vegetation on the banks.One has still to ensure that the dischargecapacity stipulated in the ProvisionalOrder governing the watercourse is notdiminished, however. There is usuallyconsiderable leeway to do so, though,since the cross-sectional profile of manyof the watercourses is actually greaterthan that stipulated (5) (Figure 1.2).

Environmentally sound maintenancecan have a markedly beneficial impact onthe watercourse environment. In FunenCounty, it has thus been shown that the

Figure 1.2. Three

cross-sectional

profiles of the

upper reach of the

river Gudenå. The

thin line indicates

the profile in 1992,

while the thick line

indicates the profile

as it should be

according to the

Provisional Order of

1941 (5).

Introduction

0 1 2 3 4 5 6 m

2,387 m from the source1,123 m from the source633 m from the source

Hei

gh

t ab

ove

sea

leve

l (m

)

60

61

62

63

64

65

66

0 1 2 3 4 5 60 1 2 3 4 5 6

10

maintenance practice has improvedphysical conditions in thousands ofkilometres of Danish watercourse duringthe same period (7). Thus in the majorityof Danish watercourses, good physicalconditions will have to be ensured byenvironmentally sound maintenance. Inaddition, environmentally sound main-tenance is often a precondition forfulfilment of the aims of a rehabilitationproject. For example, environmentallysound maintenance can hold sandmigration in check so that newly establishedspawning grounds can function (7).Environmentally sound maintenance isalso a precondition if there are to besuitable hiding places for the trout fry.

Environmentally sound maintenancedoes not enjoy the same public attentionas restoration projects. With restorationwork, the public can see improvement inthe watercourse from day to day. Incontrast, the improvements brought aboutby environmentally sound maintenancetake place gradually over longer periods.Restoration therefore has an impact overand above that on the watercourse reachin question, by creating general interestin the endeavours to improve our water-courses.

As mentioned in the introduction, thisbook primarily focuses on restoration.Thus despite the important role played byenvironmentally sound maintenance, itwill not be discussed further.

The need for rehabilitation

When assessing the need for watercourserehabilitation, a first step is to determinehow many watercourses are impoverishedin comparison with what one considers tobe a naturally functioning watercourse.That a watercourse is naturally function-ing does not necessarily mean that it isuntouched. Thus even in the modernlandscape, there are watercourses thathave retained their natural functions tosuch an extent that they serve as goodhabitats for a diverse fauna andflora, and

Figure 1.3. In

county water-

courses on Funen,

the trout popula-

tion has increased

in step with the

introduction of

environmentally

sound watercourse

maintenance. In the

municipal water-

courses, in contrast,

the trout popula-

tion has remained

sparse, probably

largely due to hard-

handed mainte-

nance (6).

Such “deposit-based” meanders oftenhave difficulty in cutting through thewatercourse’s cross-sectional profile andinto the adjacent terrain to develop anatural freely meandering watercoursewith erosion-based meanders. Given therelatively low slope of Danish water-courses, the development of “erosion-based” meanders will take a long time,often 100 years or more.

With physical restoration, the timeframe is much shorter. Using an excavatorone can rapidly excavate new meanders.Similarly, one can reopen culverted reaches,one can remove obstructions and one canlay out new stone and gravel beds inplaces where only a sandy bed remains.Moreover, when it comes to reopeningculverted reaches or restoring free passageat obstructions such as weirs and dams,there is no alternative to physicalrestoration, not even in the long term.

Excavators are expensive to run,however. Thus the total length of water-courses improved over the last 10 yearsby remeandering and reopening ofculverted reaches in Denmark is estimatedto be less than 100 km – and perhapseven only half of that. In contrast, theimplementation of environmentally sound

in which the ecological and hydrologicalprocesses function appropriately.

Another way of assessing the need forrehabilitation is to consider the largenumber of watercourses that do not yetlive up to their quality objective. A Danishnationwide survey encompassing morethan 11,000 watercourse monitoringstations revealed that at two thirds of thestations, the watercourse did not complywith the stipulated quality objective (8).While one reason for this is continueddischarge of sewage effluent, in the vastmajority of cases poor physical conditionsare responsible. Thus, according to thisDanish survey, 26% of watercoursesunder 2 metres in width failed to complywith their quality objective because ofhard-handed maintenance and poorphysical conditions (Table 1.1).

Watercourses of natural originAs mentioned earlier, there are approxi-mately 30,000 km of watercourse ofnatural origin in Denmark (7). These arewatercourses created by the geologicalforces of nature.

In addition, there is an equivalentlength of canals and drainage ditches.However, these are only the relics of atime when there were even more, manyof the field drains having disappearedagain after it became technically andeconomically feasible to drain the fieldswith drainpipes. No statistics are availableas to how many kilometres are involved.Typically, though, nearly all the ditchesand brooks in cultivated fields will havedisappeared into drainpipes because theywere in the way of work in the fields. Onthe other hand, the open ditches andbrooks in woods and forests have beenleft open because tree roots wouldotherwise have rapidly blocked thedrainpipes.

On the basis of cartographic studies,Brookes (9) has estimated that of the30,000 km of Danish watercourse ofnatural origin, only about 900 km haveretained their natural form. The percent-

Introduction

0-1 1-10 11-20 21-50 51-100 >100

Trout density (No. per 100 m2)

0

20

40

0

20

40

60Pe

rcen

tage

of

wat

erco

urse

sCounty watercourse

Municipal watercourse

19851991

11

age of watercourses that have retainedtheir natural form varies considerablyfrom county to county (Figure 1.4). It ishardly surprising that the greater theformer drainage intensity in a county, thelower the percentage of watercoursesthat have retained their natural form.

The watercourses have lost theirnatural form because of channelizationand deepening, and the very hard-handed maintenance formerly practised –a maintenance practice that shouldrightly be called regulation.

It is common ecological knowledgethat the more diverse the environmentalconditions, the more diverse the faunaand flora (10). The uniformity ofchannelized and deepened watercourses,which is maintained by hard-handedmaintenance, thus provides poor conditionsfor life.

In contrast, the great physical variationin current velocity, depth, bed sub-stratum, vegetation, and bank form thatcharacterizes naturally meanderingwatercourses provides a wide variety ofhabitats for plants and animals.

In a naturally meandering watercourse,the distance between meanders isgenerally approximately 10–14 times thewidth of the watercourse when full to theedge (Figure 1.5). This distance is referredto as the meander wavelength. Thecurrent in a meandering watercourseaffects its bed and sides with forces thatare much smaller than in a corresponding

Figure 1.4.

Percentage of

watercourses having

retained their

natural form shown

for each of the 14

Danish counties (7).

Table 1.1. Reasons

for noncompliance

with quality

objectives for

watercourses under

two metres in width

(8).

channelized watercourse. This is especiallyso during periods of high discharge,when it is natural for the meanderingwatercourse to flood its banks. Thisreduces erosion in comparison with whatwould occur if discharge of correspondingmagnitude was forced through achannelized watercourse. Erosion alsotakes place in meandering watercourses,but the special “corkscrew” form of thecurrent ensures that the eroded materialis deposited again immediately down-stream of a meander bend. Sand migrationis thus considerably less in a meanderingwatercourse than in a channelizedwatercourse.

FloodingRehabilitating channelized watercoursesin such a way as to restore a more naturalpath and enable the watercourse to floodits meadows often has a positive influenceon hydrological conditions in downstreamreaches. Thus allowing a watercourse toflood its immediate surroundings reducesthe risk of flooding further downstream,where the consequences can be moresevere due to the size of the watercourseand the magnitude of discharge. Inaddition, the flooded areas temporarilystore the water such that oscillations

Cause of problem %

Poor physical variation due to channelization 15Hard-handed maintenance 11Sewage effluent from sparely built-up areas 27Sewage works effluent 22Loading from agriculture 7Low water discharge 5Ochre 5Loading from freshwater fish farms 2Miscellaneous 6

Figure 1.5. A watercourse meander.

Current, bed and depth conditions follow

fixed patterns along a watercourse’s

meanders (7).

between high and low discharge are lesspronounced.

Flooding can also have a local impact.Thus it enhances the capacity of themeadows to denitrify nitrate derived fromthe cultivated fields because the anoxiczone is greater in a wet meadow.

In addition, flooding can reduce therisk of iron leaching from meadowscontaining pyrite. With channelized anddeepened watercourses the groundwater

Introduction

60 50 40 30 20 10 0 10 20 30

Watercourses still having their natural form (m km-2)

% of totalCounty

% drained

Drained area

(1,000 ha)

Nordjylland

Viborg

Aarhus

Ringkjøbing

Vejle

Ribe

Sønderjylland

Funen

Vestsjælland

Roskilde

Frederiksborg

Storstrøm

Copenhagen

Bornholm

30

40

45

34

48

32

62

55

78

57

71

80

64

60

129

109

136

112

98

67

183

135

162

33

45

198

>

>22

(gravel)

Deposition

Riffle

(mud)

Pool

DepositionPool

12

References to Chapter 11 Nielsen, J. (1995): Fish requirements as to

watercourse physical condition – A selectionof existing knowledge (in Danish withEnglish summary). – Environmental ProjectNo. 293, Danish Environmental ProtectionAgency. 129 pp.

2 Osborne, L.L., Bayley, P.B. & Higler, L.W.(eds.) (1993): Lowland stream restoration:Theory and practice. – Freshwater Biology(special issue) 2: 187-342.

3 Hunt, R.L. (1992): Evaluation of trouthabitat improvement structures in threehigh-gradient streams in Wisconsin.– Technical Bulletin No. 179, Department ofNatural Resources, Madison. 210 pp.

4 Nielsen, J. (1994): Fish passage at obstruc-tions in Danish streams. – Vejle CountyCouncil. 9 pp.

5 Hansen, H.O. (in press): Remeandering of aDanish headwater stream: The river Gudenådemonstration project. – Internat. Verein.Limnol.

6 Wiberg-Larsen, P., Petersen, S., Rugaard, T.& Geertz-Hansen, P. (1994): Better water-course maintenance increases the number offish (in Danish). – Vand & Jord 6: 263-265.

7 Madsen, B.L. (1995): Danish Watercourses– Ten years with the new Watercourse Act:Collected examples of maintenance andrestoration. – Environmental News No. 11,Danish Environmental Protection Agency.206 pp.

8 Friberg, N., Græsbøll, P. & Larsen, S.E. (inpress): Causes of the generally poor state ofsmaller Danish watercourses (in Danish). – Environmental Project, Danish Environmen-tal Protection Agency.

9 Brookes, A. (1984): Recommendationsbearing on the sinuosity of Danish streamchannels. – Technical Report No. 6,Freshwater Laboratory, Danish Environmen-tal Protection Agency. 130 pp.

10 Thienemann, A. (1950): DieVerbreitungsgeschichte derSüsswassertierwelt Europas (in German).– Die Binnengewässer Band XVIII, Stuttgart.

11 Ansbæk, J., Jensen, F., Schultz, K.E. &Aagaard, P. (1981): The significance ofwatercourses to society (in Danish).– Freshwater Laboratory, Danish Environ-mental Protection Agency.

12 Ejbye-Ernst, M. (1993): Watercourse fishpopulations (in Danish). – Ribe CountyCouncil, Technical and EnvironmentalDepartment. 39 pp.

table sinks in the adjacent fields. As aresult, a greater area becomes oxic, andthe pyrite present in the soil might bewashed out as ochre. In some parts of thecountry, ochre contamination haseffectively precluded the presence of adiverse watercourse fauna.

Remeandering of a watercourse canthus remedy some of the consequencesof former channelization and deepeningof the watercourse. Moreover, it can havea positive influence on water quality, notjust in the watercourse itself, but also inother aquatic areas.

Restoring continuity betweenwatercourse reachesUniform physical conditions is just one ofthe problems associated with channelizedwatercourses. Another is that the water-course fauna is often hindered frommoving freely upstream and downstreamby dams and other obstructions.

Many of the obstructions wereestablished in connection with channeliza-tion, when weirs were built to even outthe former gentle fall over the meanders.Right up to the end of the 1970s, closelyspaced obstructions were common evenin relatively small river systems (11)(Figure 1.6). In some places, obstructionshave hindered the free passage of fish forcenturies. Despite concentrated efforts toremove the obstructions, considerablenumbers still remain. An example is RibeCounty, where large areas were stillclosed to migratory fish in 1993 despite

Figure 1.6. Obstruc-

tions in the Vegen

river system late in

the 1970s. The

obstructions

hindered trout in

reaching the

spawning grounds.

Figure 1.7. Water-

courses of Ribe

County that were

still closed to

migratory fish in

1993 (12).

considerable efforts to make theobstructions passable (Figure 1.7).

Despite the many rehabilitationprojects that have already been under-taken in Denmark, there still remains aconsiderable need to carry out furtherprojects in order to achieve the diverseflora and fauna that we expect in ourwatercourses.

Introduction

Obstruction for salmonidsSpawning gravel

13

2From idea to realityMogens Bjørn Nielsen

The present chapter discusses the mostimportant considerations, technicalaspects and legally required approvalsthat are involved when undertaking awatercourse rehabilitation project inDenmark. As the examples in this bookillustrate, the purpose of rehabilitation,the solutions, and the interests that haveto be taken into consideration vary fromwatercourse reach to watercourse reach.

The chapter examines restoration stepby step – from the initial idea untilcompletion of the project in the field. Inaddition, a check list is included at theend of the chapter that Danish authoritiesshould find useful when drawing upprojects aimed at improving watercoursesand riparian areas. If modified to takelocal conditions into account, the procedurecould also be used by the authorities ofother countries.

Course of a Danishrehabilitation projectCarrying out a watercourse rehabilitationproject in Denmark is often a matterrequiring patience. The following stagesare normally involved:. Initial idea. Pilot studies. Contact to landowners and provisional

acceptance

. Coupling of interests between land-owners, the public and the authorities,and drawing up of the project. Approvals and processing by theauthorities. Clarification of financing. Construction – the physical work. Assessment and follow-up.

By far the majority of the projects areundertaken by the Counties and Munici-palities in collaboration with one or moreother parties. The Counties have drawnup a policy and strategy in the environ-ment and nature area, and administer themajority of the laws pertaining to water-courses and the landscape. In addition,many of the Municipalities have plans fortheir watercourses, and in some casesalso have restoration plans. There are alsoexamples of projects having been under-taken by private interest groups or theState.

The European Centre for RiverRestoration at the National EnvironmentalResearch Institute in Silkeborg houses alarge collection of reports and projectdescriptions pertaining to watercourserestoration. There one may obtain inspira-tion and benefit from the experiencegained in earlier projects. In order to beable to expand the collection and buildup a broad European base of information,

14

the Centre is very interested in receivingproject descriptions, assessments andother experiences on restoration projectscarried out in European countries.

Initial ideaThe initial idea for a watercourse restora-tion project typically comes from:

. Private individuals. Groups of landowners. Residents associations. Interest groups, e.g. angling associa-tions, nature conservation societies,ornithological societies. Municipal Councils, municipal techni-cal departments. County Councils, county landscapedepartments, county environmentaldepartments.

Over the last few years, the Counties andMunicipalities have increasingly receivedenquiries from landowners concerningrestoration of watercourse reaches ontheir property. In some cases, the enquirieshave come from residentsassociations. Infact, the question “Couldn’t we have ourformer meandering stream back in themeadow?” once posed by the residentsof Bevtoft in Sønderjylland County wasthe impetus for one of the first majorremeandering projects in Denmark – therestoration of 2 km of Gelså stream (seeChapter 5).

Marginalization of riparian areas andthe fact that an increasing number ofrural properties are being overtaken byurbanites also increase the possibilities forundertaking watercourse restorationprojects. Enquiries from establishedinterest groups tend to be somewhatmore organized, their members oftenhaving a very good knowledge of whichwatercourses would benefit fromrestoration. Ideas also arise in so-called“Regional Countryside Councils” set upby the Counties, and in which the“green” organizations are representedtogether with farming organizations, etc.

acquired, for example showing theformer course prior to channelization,biological conditions should be investi-gated, various measurements made andsoil samples collected. In addition,information on discharge in the water-course or in the catchment area shouldbe obtained, larger-sized technicalstructures in and alongside the water-course should be checked, and possiblelegal constraints on the project beinvestigated. On this basis, an assessmentshould then be made of whether or notthe project is technically realistic. Theresults of the pilot study will subsequentlybe incorporated in the detailed projectdescription.

Contact to landowners andprovisional acceptanceAssuming the pilot study or the outlineproject does not preclude the projectbeing undertaken, thereafter followswhat is often the most important phase.Thus beforeproceeding with the project,it is advisable to go over the project ideawith the landowners involved. The firstcontact should be made personally to eachindividual landowner. It is very importantthat the project outline presented tothem is clearly only a proposal. Thisensures that it will be possible to incorpo-rate local ideas and wishes into theproject, something that is only normallypossible provided one is not technically orpolitically bound to a particular solutionbeforehand.

It is inadvisable to arrange and under-take a large public meeting at too early astage, when the basis for the project istoo loose and only the basic idea and asummary pilot study are available. Thedemocratic rights of parties involved areassured by the mandatory periods for thesubmission of objections and appealsduring the various stages of the approvalprocess (Figure 2.1). Thus the publicmeeting should not be held until suchtime as one has discussed the projectwith the landowners affected andincorporated some of their ideas andcomments into the project, but is still opento possible further changes to the project.

The usual outcome is that not all thewishes and comments can be followedsimultaneously, and the choice betweenpossible solutions thus becomes apolitical decision. Hence it is normally agood idea that politicians from theresponsible watercourse authority alsoparticipate in the public meeting. Theinvolvement of politicians signals toparticipants that there is more to theproject than just some technicians’ idea.Moreover, one is more likely to acceptsolutions arrived at on a political basiswhen one has seen and heard thepoliticians in question.

The fact that restoration can also leadto a more varied nature in the watercourseand its immediate surroundings, andthereby to better hunting and fishing, cansometimes help tip the balance in favourof undertaking such projects.

Pilot studiesIn order to obtain a first impression ofwhether an idea is scientifically defensible,a pilot study or an outline project shouldbe made. Relevant maps should be

The stream Rind

restoration project.

From idea to reality

15

Coupling of interests between land-owners, the public and the authori-ties, and drawing up the projectBefore drawing up the project it isimportant to formulate one or more clearobjectives. A restoration project can oftentake account of many different environ-mental and natural interests, and thewider the proposal is, the more backing itwill often be possible to obtain. On theother hand, though, it is not possible totake account of all interests at the sametime and place. Priorities have thereforeto be established.

A watercourse restoration projectcomprising restoring the watercourse toits original meandering path involves

more than just restoring the watercourseitself. Thus, riparian areas such as banksand meadows will often also be affected.In some cases, watercourse restorationinvolves raising the groundwater tableand implementing ochre removal.

The objective when restoringwatercourses and adjacent wetlandscould be one or more of the following:

. Better physical conditions in thewatercourse. Enhanced self-purification capacity inthe watercourse and greaterdenitrification of nitrogen in the wetmeadows. A more varied landscape

. A greater number of more variedhabitats for (threatened) plant andanimal species. A greater number of more varieddispersal corridors for plants andanimals. Reduced ochre loading. Protection of groundwater resources. Enrichment of outdoor life, includingangling and hunting. Compliance with international obliga-tions (conventions, protectedwetlands, etc.).

With restoration projects involvingremeandering and raising the water-course bed, possible results include:

. A meandering watercourse withgreater landscape value. Less ochre loading (in cases wherethere is ochre in the vicinity of thewatercourse). Wetter meadows with greater nutrientturnover. Greater physical variation in both thewatercourse and the adjacent areas. A greater number of different speciesof animals and plants. Better recreative possibilities, e.g.angling, walking, sailing, bird watch-ing and hunting. Enhanced quality of life.

When prioritizing possible projects,inclusion of the following considerationswill help ensure the greatest environmen-tal and natural return on the investment:

. Ensure that the investments andchanges are permanent. Aim for low costs for purchase andconstruction. Ensure that there are only few or nomaintenance costs once the projecthas been completed. Take account of several interestssimultaneously (as described above). Obtain good political and localbacking.

Project proposal

Comments from otherpertinent authorities

Initial approval by thewatercourse authority

Public announcementof the project

– 4-week appeals period(With public hearings

– 8 weeks notice)

Decision on possiblefinancial questions

(possible compensation)

Watercourse authorityannounces approval

– 4-week appeals period

Final decision bythe Danish EPA

Project undertaken Project rejected

Decision announced– 4-week appeals period

Decision bythe Danish EPA

Land Tribunal– 8-week appeals period

Land Tribunal Board of Appeals

Possible approval pursuant to the Nature Protection,Environmental Protection

and Water Supply Acts

SettlementNo

settlement

Appeal

No

Appeal

Appeal

Appealrejected

Ap

pea

l acc

epte

dFigure 2.1.

Schematic represen-

tation of the steps

involved in the

approval of water-

course regulation

and restoration cases

by the Danish

authorities.

From idea to reality

16

Watercourse restoration projects oftenhave to be drawn up using amultidisciplinary approach involvingtopics such as:

. Water quality. Hydrology and discharge. Biological conditions. Technical installations, such as pipesand cables under and above ground atwatercourses, bridges, houses andother structures, etc.. Legal aspects, as described below.

From the legal point of view, thefollowing measures are also watercourseregulation:

. Remeandering of a watercourse. Various improvements at weirs,including:

Construction of fish laddersSplit-stream bypass reachesRebuilding or removal of weirs/damsReopening of culverted reaches.

The regulations governing how theauthorities are to process projects aimedat improving watercourses are stipulatedby the Ministry of Environment andEnergy in a 1983 Statutory Order. Thiscovers both watercourse regulation andwatercourse restoration. These regula-tions have to be followed by the water-course authority in all cases, irrespectiveof from where and whom the originalidea or initiative for the project derives.The approval process is shownschematically in Figure 2.1.

Proposals for watercourse regulationand restoration are submitted to theCounty Council or Municipal Councilwith a view to obtaining the politicaldecision of the watercourse authority toproceed with the case.

The proposal shall include:

1. An account of the purpose of theregulation project and a justification ofthe project.

2. The necessary outline maps anddetailed plans.

3. A summary of the properties affectedby the project and a list of landownersand users who should be involved inthe project.

4. An estimate of costs including aproposal for their apportionment.

5. A timetable for the work.

If the project is undertaken as an actualrestoration project, the proposal mustinclude the following:

1. An account of the quality objective forthe watercourse and the aim of theproposed restoration project.

2. An account of the pilot studies onwhich the project is based.

3. An account of the consequences ofthe restoration project for dischargeand drainage.

4. Information on the watercourse’spresent and future form and dischargecapacity, and on the associated watertable conditions.

5. Information on the planned restorationmeasures and their location in thewatercourse.

6. The necessary sketches and maps,including an outline plan in a suitablescale.

7. A timetable for the work.8. An estimate of construction and

running costs.

If the watercourse authority decides toproceed with the case, the proposal islaid open to the general public for aperiod of at least 4 weeks in regulationcases, and at least 8 weeks in restorationcases. Announcements are usually madein the daily press or in local newspapers.Landowners and other interested partiesare informed in writing. At the sametime, the proposal is sent to organizationshaving the right of complaint (The DanishAnglers Federation and the DanishSociety for the Conservation of Nature).As many projects involve riparian areas inthe open countryside, it is often also agood idea to inform the local agriculturalorganizations. The proposal is simultane-ously submitted for hearing at therelevant authorities, which is always theCounty Council, but sometimes theMunicipal Council as well.

In all cases, it is required to submit anevaluation of the project in relation to thequality objective for the watercoursestipulated by the County Councilpursuant to the Environmental ProtectionAct. The majority of cases also require theapproval of the County Council pursuant

Approvals and processing by theauthoritiesRestoration is governed by Part 8 of theDanish Watercourse Act (Box 1.2). Thisaims to improve a watercourse’s qualityso that it corresponds to the qualityobjective for the watercourse stipulatedby the County Council pursuant to theEnvironmental Protection Act. In addition,though, it requires that the watercourse’sdrainage capacity should not be affectedto any great extent.

Developments in the restoration areahave overtaken legislation, however,which stems from the early 1980s. Thus,many of the restoration measures in usein the 1990s include elements ofwatercourse “regulation” in the form ofthe remeandering of channelized reaches,and hence are encompassed by Part 6Section 16 of the Watercourse Act (Box1.2).

A new watercource

being excavated.

From idea to reality

17

to the provisions of the Nature ProtectionAct. With such approvals, there is also astatutory 4-week complaints period. Inrare cases, approval is also required fromthe Ministry of Agriculture and Fisherypursuant to the Freshwater Fishery Act.Thus Section 33 of the Act states that“before permits are issued or decisionsreached concerning measures that canaffect the passage of fish, fishery and thefish fauna in general, the plans shall besubmitted to the Ministry of Agricultureand Fishery for comment”.

Due to the often rather complicatedlegal procedures involved, it is advisableto contact the relevant county authoritiesin advance to find out what approvals arenecessary for the watercourse reach inquestion and the measures planned. Inaddition, when drawing up the detailedproject it is advisable to evaluate howcomprehensive the impact assessmentstudies should be (see below under theheading “Evaluation and follow-up”).When agreeing to subsidize larger-sizedprojects, the Danish EnvironmentalProtection Agency will normally requirethat the environmental impact of theproject be documented in some way orother.

Based on the project proposal andwhatever comments arise during thepublic hearing phase, the watercourseauthority issues final approval for theproject.

Before this can be done, however, thefinancial aspects have to be clarified (seebelow) and, as mentioned above,whatever other approvals might benecessary have to be obtained.

Thereafter follows a 4-week appealsperiod pursuant to the Watercourse Act,irrespective of whether the case concernsregulation or restoration. The possibilityof appeals is intended as an emergencybrake in that the watercourse authority’sapproval should already have taken fullyinto account the various interests involvedand the comments and remarkssubmitted.

Appeals have a postponing affect suchthat a project may not be initiated beforethe appeal authority has issued a ruling.In these cases, the appeal authority is theDanish Environmental Protection Agency.However, in cases where it seems mostlikely that the appeal will be denied, theAgency can issue approval for initiation ofconstruction work. Some appeals areprocessed relatively rapidly, while somecan take several months.

With some projects, it is necessary tochange the existing ownership conditionsand property boundaries. The landownerscan have an interest in exchanging land,for examples if their fields are scatteredrather than being congregated nearthefarmhouse. In addition, it is a legalrequirement that property boundariesand ownership records be correctedwhen a piece of land changes hands. Themost natural would be for the authorityresponsible for the project to take care ofthe task of updating the Land Registry.

FinancingBefore the watercourse authority canissue final approval for a watercourseproject, financing has to be clarified.Many projects are in effect collaborative

endeavours, and financing often derivesfrom a number of sources in the form ofcash subsidies or labour. In some cases,labour undertaken by landowners andangling clubs is part of the financing. Inother cases, land is provided free ofcharge or compensation.

Restoration can sometimes help solverecurring problems with the maintenanceof a watercourse. Examples are reacheswhich continually silt up or where thebanks continually collapse, or culvertedreaches where costly replacement of thepipes is needed. In such cases, therelevant watercourse authority couldprofitably capitalize future maintenancecosts and instead solve the problem byrestoring the watercourse.

The most important additional sources offinancing are:. Local sources: Landowners, associa-

tions (residents associations, touristassociations, anglers) and the Munici-pal Council. Regional sources: County funds forwatercourse restoration, countrysiderehabilitation and management, andsubsidies for specific use of theriparian areas, e.g. for grazing

The river Brede

restoration project.

From idea to reality

18

. State sources: The Danish Environmen-tal Protection Agency’s funds forwatercourse restoration and ochreremoval, the National Forest andNature Agency’s central pool forcountryside rehabilitation. Various funds, firms, companies andprivate individuals. In a few cases, subsidies for very largeprojects have been obtained under theEU LIFE programme (e.g. the riverBrede, the Skjern river delta, and theheadwaters of the river Gudenå).

Check listfor the project descriptionA useful way of arranging a detailedproject description that complies withlegal regulations and requirementsregarding both regulation and restora-tion projects is as follows:

A. Introduction. Origin of the idea and location ofthe area. Purpose of the project. Summary of the physical measuresintended specifying exactly what isto be done.

drainage from the individual landowner’sproperty, as well as for future physicalconditions in the watercourse andconsequently for nature and theenvironment. In addition, supervisionensures that the funds expended on thework are used in a defensible andpolitically approved manner.

The call for tenders only has to bemade at the EU level in the case of verylarge construction projects, i.e. projectswhere the total construction costsamount to ECU 5 million or more.

Evaluation and follow-upPrior to each individual project, oneshould assess how comprehensive theimpact assessment studies should be. Inall cases, follow-up should be undertakenfor a period following completion ofconstruction work to ensure that possibledamage or undesirable consequences ofthe project are remedied. In addition, ascientific evaluation of the project by theauthority in charge is also necessary. Thisensures that valuable experience isgathered for use in future projects.

Another important matter is to reachagreement concerning maintenanceobligations and division of responsibility.Ideally, this should be clarified inconnection with approval of the project.However, from experience we know thatthis is not usually done until aftercompletion of the work.

A new stone riffle

and two-step

profile.

ConstructionHow extensive this part of the projectdescription needs to be depends on theextent of the planned construction work.If the watercourse authority decides thatthe project shall be undertaken bycontractors, a call for tenders will have tobe prepared. The call for tenders includesspecial descriptions of the work which,together with the detailed project, formthe basis for the contractor to undertakethe construction work. The rules in theCompetitive Tendering Act apply inDenmark in connection with the protec-tion of tenders, and it is recommended toseek the advice of persons with a soundknowledge of the Act.

An important task is to ensureeffective supervision of the constructionwork. This ensures that the project isundertaken in accordance with thestipulated conditions, dimensions, etc.Among other things, this is important for

From idea to reality

19

B. Description of existing conditions. General description of the locality (location,terrain, physical conditions, surveys). Preservation and regional planning con-straints, i.e. the Preservation Scheme,preservation orders and constraintsstipulated in the County Plan (raw materialreserves, EU Bird Protection Areas, environ-mentally vulnerable agricultural land, etc.). Land use (cultivation, recreational or otheruses). Fauna and flora (collation of existingknowledge/reports and new,supplementary investigations). Quality objectives and water quality(recipient quality plan, pollutional state). Drainage and discharge conditions (waterlevel, discharge, catchment size andcharacter, groundwater conditions,drainage conditions and the provisionsstipulated in the Provisional Ordergoverning the watercourse). Soil conditions. Information on specialconditions such as soft bed or potentiallyochreous areas. Valuable information canoften be obtained from existing studies inthe area. In addition, one should be awarethat it is sometimes necessary to undertakesediment analyses, typically for the heavymetals lead, cadmium, mercury and nickel.This has to be done if the excavated earthis to be dispersed on agricultural land. Thecounty authorities have information onregistered contaminated lands and ochreousareas. Technical installations, e.g. various cablesand pipes (water, sewage, telephone, gasand electricity), roads, footpaths and othercrossings, masts, structures (weirs, dams,etc.), overflows, inlets, etc. Local utilitycompanies and the Municipality’s technicaldepartment have the relevant information. Ownership (private, public, Land Registryentries, cadastral maps).

C. Planned measures. Description of the planned constructionwork suitable for preparing the call fortenders. Follow-up work, including re-establishment,sowing, planting, fencing, bridges andfootpaths.

D. Results and consequences. Expected future conditions, includingwater levels, discharge, groundwaterconditions, water quality, and flora andfauna. Consequences for land use. Future ownership. Monitoring and impact assessment.

E. Necessary permits – summary. Pursuant to the Watercourse Act. Pursuant to the Nature Protection Act. Pursuant to the Freshwater Fishery Act. Pursuant to the Ochre Act. From landowners. Review of the property’sentry in the Land Registry to determineownership, and to ensure that registeredrights and easements are not violated. Inaddition, easements can reveal informationon the location of technical installations,pipes and cables, road rights, etc. Whenclarifying ownership and agreements withlandowners, one has also to take intoaccount the possible rights of third parties.Such rights are not necessarily recorded inthe Land Registry entry for the property,and in agricultural areas will often concernleasehold agreements. Ask the ownerabout such rights and enter into anagreement with the owner thatclarifieswho is to cover, for example, aleaseholder’s crop losses caused byconstruction work.

F. Timetable. Pilot project. Preliminary discussions with landowners. Political processing of the projectapplication. Possible public hearing. Public phase. Final clarification of financing. Necessary approvals additional to thoseunder the Watercourse Act, incl. appealperiods. Final approval pursuant to theWatercourse Act, incl. appeal periods. Construction phase. Follow-up, including updating the LandRegistry and deciding future division ofmaintenance obligations and responsibility.

G. Economic aspects. A precise budget estimate and a summaryof financing.

H. AnnexesFor a typical major project the followingannexes will be relevant:. Outline maps in scale 1:100,000 and1:25,000. Old maps of the area. Survey/survey maps. Planning conditions. Existing longitudinal and cross-sectionalprofiles. Water discharge, water level, hydrographs. Present ownership. Present land use. The measures planned in the project. Coming longitudinal and cross-sectionalprofiles. Miscellaneous detailed drawings. Future ownership. Future land use.

From idea to reality