Silva v Ku-ring-gai Council

[2009] NSWLEC 1060

Land and Environment Court

of New South Wales

CITATION:

Silva v Ku-ring-gai Council [2009] NSWLEC 1060

PARTIES:

APPLICANT
Nelson Silva

RESPONDENT
Ku-ring-gai Council

FILE NUMBER(S):

10805 of 2008

CORAM:

Taylor C

KEY ISSUES:

DEVELOPMENT APPLICATION :- to pipe an existing open channel watercourse; definition of rivers; application of Water Management Act to tributaries of larger rivers

LEGISLATION CITED:

Environmental Planning and Assessment Act 1979
Land and Environment Court Act 1979
Rivers and Foreshores Improvement Act 1948
Water Managment Act 2000
Local Government (General) Regulation 2005
Ku-ring-gai Council’s Development Control Plan 38 and 47
State Environmental Planning Policy (Sydney Region Growth Centres)
Ku-ring-gai Planning Ordinace Scheme
Ku-ring-gai Council Riparian Policy 2004

CASES CITED:

Narrambulla Action Group Inc v Mulwaree Council 41068 of 1995 [1996] NSWLEC 199
Gartner v Kidman [1962] HCA 27; (1962) 108 CLR 12
Knezovic v Shire of Swan-Guildford [1968] HCA 38; (1968) 118 CLR 468 (21 June 1968)
Warringah Council v Ardel Limited and Anor [2000] NSWLEC 7
Ross G Mitchell v John Baptist Vella and Mary Magdalan Vella [1998] NSWLEC 250
Don Burke and [16] others v Hawkesbury City Council & Ors [2001] NSWLEC 222
BGP Properties Pty Limited v Lake Macquarie City Council [2004] NSWLEC 399

TEXTS CITED:

Gore, D. and Taylor, M.P. 2003, Australian Journal of Earth Sciences, 50, 467-470.
Taylor and Stokes (2005a) in the Environment Planning and Law Journal, 22, 193-211; and
Taylor and Stokes 2005b in the Australian Geographer, 36 (2), 183-200
Thoms and Sheldon, 2000, in Regulated Rivers: Research and Management, 16, 375–383.
Williams et al. (1998) in Wetlands (Australia), 18(1), 25-48),

DATES OF HEARING:

21 October 2008, 1 December 2008 and 28 January 2009

 
DATE OF JUDGMENT: 

6 March 2009

LEGAL REPRESENTATIVES:

APPLICANT
Mr C. Gough, solicitor
of Storey and Gough Lawyers

RESPONDENT
Dr J. Smith, solicitor
of Deacons

JUDGMENT:

THE LAND AND
ENVIRONMENT COURT
OF NEW SOUTH WALES

Taylor C

6 March 2009

10805 of 2008 Nelson Silva v Ku-ring-gai Council

Judgment

1 This appeal arose following the refusal by Ku-ring-gai of a development application (DA0415/08) by Mr Nelson Silva to pipe an existing open channel watercourse at 27 Miowera Road, North Turramurra.

2 The matter before the Court on January 28th commenced initially as an on-site s 34 conciliation conference. The parties could not come to agreement at the initial on-site conciliation on 21st October 2008, so the conference was terminated. The parties agreed to the matter proceeding to adjudication by the Court under s 34 (4)(b) of the Land and Environment Court Act 1979. This judgment is under s 34 (5) of the Act. The parties agreed that I could have regard to the evidence and submissions from the s 34 conciliation conference phase of the proceedings.

The Proposal and site

3 The subject site is located on the eastern corner of Miowera Road between Normurra Avenue and Somerset Avenue in Turramurra. The site contains a dwelling house on land that slopes from the north-west corner (RL 143.85) to the south-east corner (RL 133.83) and has a steep cross fall (north-south) of approximately 5 metres. The watercourse runs through the south-east corner of the site.

4 The development application DA0415/08 is for the approval of a reinforced concrete pipe with a diameter of 1050 mm, approximately 28 m in length, to be placed in the bed of an unnamed watercourse at the rear 27 Miowera Road, Turramurra, North Sydney so as to capture and transfer runoff. The remaining area of the channel is to be backfilled and levelled, the result being that the existing exposed watercourse in the property will no longer be evident. I was informed that the adjoining property to the west (upstream) through which the watercourse runs is also proposed to be piped, but that this does not form part of the application.

5 The watercourse to which the application applies to, forms part of a single channel, which drains eventually to Cowan Creek. The catchment is now highly urbanised, a process that appears to have begun in earnest from c.1950’s onwards (Exhibit F, aerial photograph from 1951).

6 According to the evidence provided by Mr Tilly, a geomorphological and hydrology expert, on behalf of the Applicant, the watercourse is comprised of 74 m (24.7 %) of open channel with approximately 226 m (75.3 %) of piped watercourse (Exhibit D). The proposal at 27 Miowera Street will result in a loss of approximately 34 % of the remaining open sections of watercourse.

7 The catchment area of the watercourse at the downstream boundary of 27 Miowera Avenue (the subject site) was estimated by Mr Tilly to be a maximum of 10.1 ha. Where the watercourse is no longer piped at the rear of Somerset Avenue (Exhibit D) it was estimated by Mr Tilly to be a maximum of 16.6 ha. The watercourse is not shown as a drainage line on either of the Hornsby 1:25,000 topographic maps (editions 2 and 3) presented to the court as Exhibit E. Much of the catchment is now covered by houses and associated suburban blocks.

8 The development application raised a number of contentions from the Council, the principal items of which can be summarised as follows:

(a) The watercourse is a river as defined in the Water Management Act 2000 ( WMA ) and consequently the development application (DA) is integrated development. The DA was not supported by the NSW Department of Water and Energy.
(b) The piping of watercourses is contrary to Council and State Government policy and is contrary to the general objectives of Ecological Sustainable Development (ESD). The piping of watercourses results in negative impacts on water quality and quantity and the piping will have the effect of sterilising the subject property’s watercourse’s biology and ecology.
(c) The application does not provide a rehabilitated riparian zone of 5 m as was approved under DA1736/02 for the subject site.
(d) The proposal will have a detrimental impact upon the landscaping at the subject site and is contrary to the Council’s Ku-ring-gai Planning Ordinance Scheme (KPOS) and the DCP 38.

9 Arising from these contentions the primary questions that arose from the proceedings were as follows:

i. Is the watercourse at 27 Miowera Road that is proposed to be piped in the development application a natural watercourse or an artificially created channel?
ii. If the watercourse is a natural feature does it constitute a river as per the definitions in the WMA 2000 ?
iii. Notwithstanding the answer to the above questions, does the application to insert a concrete pipe in the watercourse have merit with respect to the ecological and physical impacts as well as the planning and broader environmental objectives for the area ?

Background – case law, planning instruments and legislative definitions of a river

10 The fundamental issue in this dispute is centred around the definition of a river and what might therefore permissible activity within such an environment with respect to its impact upon the physical and ecological functioning of that system. The definition of a river is a surprisingly complicated matter and it was one that required determination with respect to the watercourse at 27 Miowera Road.

11 The definition of a river is not a simple matter that can be applied with geographic uniformity and certainty in the Australian landscape. Taylor and Stokes (2005a) in the Environment Planning and Law Journal volume 22, 193-194; and Taylor and Stokes 2005b in the Australian Geographer, volume 36 (2), 183-184, discussed the complexity in defining a river in different geographic locations. We recorded the following relevant points:

“Accordingly, “river” can mean different things to different people. Such differences can be explained by an individual’s cultural beliefs and childhood domicile, which may have had extremely different climatic characteristics and different types of river. For example, a native of the Namib Desert may consider all rivers which drain into the Atlantic Ocean off the west coast of Africa to be bona fide rivers, even though they flow only two or three times a year and rarely reach the sea. In contrast, a person from northern Europe may think of rivers as continuously flowing bodies of water that may also be navigable for the purposes of recreation or transport. In Australia, landscapes are characterised by contrasting climate regimes: from the seasonally wet tropics of the north; to the Mediterranean climates of South and Western Australia; to the deserts in the centre and the temperate climes in southeast Australia and Tasmania. Consequently, people from different localities may have vastly different perspectives of what a river is. For example, inhabitants of Alice Springs will think of the Todd River as a watercourse that flows very infrequently while inhabitants of Launceston will never have seen the North or South Esk rivers without a copious flow of water.”

12 It is worth noting that at least 83 % of Australia’s river networks are characterised by ephemeral systems that experience semi-arid to arid (dryland) climatic regimes (see Thoms and Sheldon, 2000, in Regulated Rivers: Research and Management, 16, 375–383. With respect to NSW, Williams et al. (1998) in Wetlands (Australia), 18(1), 25-48), identified that at least 950 water bodies draining NSW were ephemeral. Nevertheless, scientific definitions do not necessarily prevail in the determination and definition of what constitutes a river in the Australian sense. In Narrambulla Action Group Inc v Mulwaree Council 41068 of 1995 [1996] NSWLEC 199 Bannon J observed:

“Dr O'Loughlin referred to the arid conditions of Australia, and it was plain to me that while his views deserve respect, he thinks of waterbodies in a scientific way, which includes waters such as Coopers Creek, but does not fit the definitions given by the Courts, taken as they are, from European conditions.”

13 Correctly or otherwise, the legislative and case-law definitions of what constitutes a river are deeply ingrained with Eurocentric perceptions of what is a river. In Gartner v Kidman [1962] HCA 27; (1962) 108 CLR 12 (30 May 1962) Windeyer J [at para. 13] referred to the often-quoted passage from Angell, J.K. A Treatise on the Common Law, In relation to Watercourses: Intended More particularly as an illustration of the Rights and Duties of the Owners and Occupants of Water Privileges, 5th ed. (1854) p. 3:

"A watercourse consists of bed, banks and water; yet the water need not flow continuously; and there are many watercourses which are sometimes dry. There is, however, a distinction to be taken between a regular flowing stream of water, which, at certain seasons is dried up, and those occasional bursts of water which in times of freshet or melting of ice and snow descend from the hills and inundate the country".

14 This approach was adopted in Knezovic v Shire of Swan-Guildford [1968] HCA 38; (1968) 118 CLR 468 (21 June 1968) by Barwick CJ who said [at para. 18]:

“It seems to me, on an examination of such authorities as exist and of the work of recognized writers on this subject, as well as the decision of the Court, that it is settled that a watercourse consists of a stream with a bed, with banks, and water. That the flow of the water in the stream is intermittent or seasonal will not prevent what would otherwise be a watercourse from being accounted such: but though it is quite true that a watercourse may exist though its bed be dry for some periods, the watercourse, in my opinion, must exhibit features of continuity, permanence and unity, best seen, of course, in the existence of a defined bed and banks with flowing water. It must, in my opinion, essentially be a stream and be sharply distinguished from a mere drain, or a drainage depression in the contours of the land which serves to relieve upper land of excess water in times of major precipitation. It is not enough that the water, when it does flow, does so in what may be seen as a defined course or channel. In the case of a drainage depression, the water being drained off can be expected to flow in the lowest portion of the contours confined by the rising levels of the adjacent land: thus water can be seen when flowing to do so in what could be called a defined channel. If the seasonal rainfall is within an average tolerance in amount and timetable, the flow in the depression may well exhibit some regularity in the depth of water flowing in the contour depression and in the extent to which it spreads as it flows. If there is some such normality in the volume flowing, the impression of a defined channel with limiting margins will be enhanced. If, as I would expect to be the case, there is considerable variation in the rainfall and in the volume and velocity of the water flowing in the depression, the impression of a defined channel may be considerably less. But, in any event, the existence of such a defined channel will not make the drainage depression a watercourse nor the limiting margins of the water's flow in a rainy season or period "banks" of a stream. Thus, though water when it flows in such a period flows in what can be called a defined channel, such a drainage depression will lack banks and a bed in the proper sense of that term, that is to say, identifiable margins of a continuous and permanent stream which contribute to its unity whether or not water is in fact continuously flowing over the bed. The word "occasional" in the quotation from Angell on Watercourses will here, in my opinion, embrace seasonal events, even if they occur with some regularity from season to season. (at p. 476).”

15 In Ross G Mitchell v John Baptist Vella and Mary Magdalan Vella [1998] NSWLEC 250 (9 October 1998) Sheahan J also considered the definition of a river and came to the same conclusion as Barwick CJ and Windeyer J in previous decisions [at para. 93]:

“I agree with the respondents' submission that for a "waterbody" to come within the definition in Part 3 of Schedule 3 EPAR, it must exhibit features of continuity, permanence and unity, and must otherwise accord with the definitions given by Barwick CJ in Knezovic and Windeyer J in Gartner. Bannon J effectively adopted these definitions for the purposes of Schedule 3 of the EPAR and I see no reason to depart from his reasoning.”

16 Sheahan J followed the same reasoning in Don Burke and [16] others v Hawkesbury City Council & Ors [2001] NSWLEC 222 (28 September 2001). In his judgement he noted the similarity of his findings as well as reliance on other relevant cases pertaining to the definition of a watercourse [para 77]:

“I can see no reason at all to depart from the reasoning in all those cases on this occasion”

It is clear from various case-law judgements that a bona fide river must have a defined bed and banks and flowing water.

17 The WMA under Dictionary defines ‘rivers’ and also states what other connecting systems should be included in any such definition:

river includes:
(a) any watercourse, whether perennial or intermittent and whether comprising a natural channel or a natural channel artificially improved, and
(b) any tributary, branch or other watercourse into or from which a watercourse referred to in paragraph (a) flows, and

18 The relevance of (b) is that it includes any other watercourse (of an unspecified nature or origin) that flows into anything that can be described as a river in (a).

19 During the on-site visit, the parties were taken to the banks of the Cowan Creek to where the watercourse draining through 27 Miowera Road flows. While there was no dispute between the parties that Cowan Creek was a river, the Applicant contended that the watercourse flowing via 27 Miowera Road was not a natural feature and therefore did not fall within the WMA’s definition of a river. Since the term ‘watercourse’ is not defined in the WMA, the Applicant took me to definitions of watercourse contained in a range of documents. These included:

20 Local Government (General) Regulation2005, s (or clause) 110 Guidelines for categorisation of land as a watercourse:

Land that is categorised as a natural area should be further categorised as a watercourse under section 36 (5) of the Act if the land includes:
(a) any stream of water, whether perennial or intermittent, flowing in a natural channel, or in a natural channel that has been artificially improved, or in an artificial channel that has changed the course of the stream of water, and any other stream of water into or from which the stream of water flows, and
(b) associated riparian land or vegetation, including land that is protected land for the purposes of the Rivers and Foreshores Improvement Act 1948 or State protected land identified in an order under section 7 of the Native Vegetation Conservation Act 1997.

21 State Environmental Planning Policy (Sydney Region Growth Centres) 2006 Dictionary:

watercourse means any river, creek, stream or chain of ponds, whether artificially modified or not, in which water usually flows, either continuously or intermittently, in a defined bed or channel, but does not include a waterbody (artificial).

22 Macquarie Dictionary (online version):

noun
1. a stream of water, as a river or brook.
2. the bed of such a stream: * But if he stays until it rains -- and this may mean years -- he will see that these dry watercourses at least have a function. —harold lewis , 1973 .
3. a natural channel conveying water.
4. a channel or canal made for the conveyance of water.

23 In each of these definitions of ‘watercourse’ there is an emphasis on natural systems. This is mirrored in part (a) of the Dictionary definition of ‘rivers’ but any notion of naturalness is equivocal with respect to part (b) of ‘Rivers’ in the WMA Dictionary. Notwithstanding this doubt, examination of the Objects of the WMA s 3 reveal the following relevant items:

The objects of this Act are to provide for the sustainable and integrated management of the water sources of the State for the benefit of both present and future generations and, in particular:
(a) to apply the principles of ecologically sustainable development, and
(b) to protect, enhance and restore water sources, their associated ecosystems, ecological processes and biological diversity and their water quality, and
(c) to recognise and foster the significant social and economic benefits to the State that result from the sustainable and efficient use of water, including:
(i) benefits to the environment, and
(ii) benefits to urban communities, agriculture, fisheries, industry and recreation, and
(f) to integrate the management of water sources with the management of other aspects of the environment, including the land, its soil, its native vegetation and its native fauna,
(g) to encourage the sharing of responsibility for the sustainable and efficient use of water between the Government and water users,
(h) to encourage best practice in the management and use of water.

24 Of particular pertinence are items (a), (b), (f) and (h). These are directed towards better-integrated, more ecological sustainable use and improvements of and best practice in the management of water.

25 The Water Management Principles in s 5 (2) that underpin the Objects of the WMA explain further the intent of the legislation. These state relevantly:

(a) water sources, floodplains and dependent ecosystems (including groundwater and wetlands) should be protected and restored and, where possible, land should not be degraded, and
(b) habitats, animals and plants that benefit from water or are potentially affected by managed activities should be protected and (in the case of habitats) restored, and
(c) the water quality of all water sources should be protected and, wherever possible, enhanced, and

(d) the cumulative impacts of water management licences and approvals and other activities on water sources and their dependent ecosystems, should be considered and minimised, and
(h) the principles of adaptive management should be applied, which should be responsive to monitoring and improvements in understanding of ecological water requirements.

26 As per the Dictionary definition of ‘Rivers’ in part (b) of the WMA neither its Objects nor the Principles exclude explicitly artificial water sources. As such they must be deemed to be inclusive in terms of watersources.

27 Other relevant planning instruments that relate to the determination of the status of the watercourse in 27 Miowera Road are Ku-ring-gai Council’s DCP 47, Water Management. The Dictionary of Definitions for this DCP does not describe what is a ‘watercourse’. Nevertheless, a waterbody is defined (p. 6) as follows:

Waterbody means a river (being a stream, whether perennial or intermittent, flowing in a natural channel, or in a natural channel that has been artificially modified, or in an artificial channel which has changed the course of a stream), a branch of the river, an estuary, tidal waters, a lake, a pond, an inlet, a bay, a lagoon or an artificial waterbody.

28 Thus, akin to the WMA, the DCP 47 definition of ‘Waterbody’ appears to be comprehensive in that it includes a waterbody that is both natural and artificial. This would include a channel and its flow whether constructed artificially by way of stormwater works or as a consequence of natural runoff and erosion processes. Accordingly, this would include the unnamed watercourse at the rear 27 Miowera Road, irrespective of its origin, natural or artificial.

29 In addition, DCP 47 at Chapter 7 – Development Adjacent to or Over Existing Drainage Systems, section 7.4 states:

Any development that includes an ‘activity’ being undertaken within 40 metres of the top of the bank or shore of ‘protected waters’, with the exception of waters administered by the NSW Waterways Authority and in certain identified circumstances, is Integrated Development. Integrated Development requires consent from at least one public body other than Council. Contact Council prior to finalising the location if the development or any works associated with that development are located within 40 metres of a waterbody.
The following controls apply to development over or adjacent to a natural waterbody:
a) No works shall be undertaken on or near a natural waterbody that would cause straightening, relocation, widening, narrowing, piping, lining or reprofiling of the natural waterbody.

30 Further, at Chapter 9 - Road and Trunk Drainage, section 9.3.4 the DCP states the following relevant points:

Note: Council does not permit the use of pipes or traditional concrete lined channels or their equivalent to replace existing open watercourses. Where new drainage channels are proposed, they must be designed and constructed in an environmentally sensitive manner that mimics the environmental benefit of a natural open watercourse.

31 In respect of piping of watercourse, the Applicant relied upon an extract of the Council’s 1993 Stormwater Management Manual that was sent to the Applicant (Mr Silva) on 18th November 2005 by the Council in relation to information of piping watercourses. At section 3.3 the Manual states the following:

For these reasons the Council has adopted a policy that seeks to preserve the natural drainage system, and hence it will not normally permit the piping of or alterations to the location of watercourse.
However, Council may consider written requests for the extension of existing piped drainage where it is adequately demonstrated that:
(a) the watercourse has insufficient capacity for the design storm; or
(b) the watercourse is significant eroded and cannot reasonably be restored; or
(c) the watercourse constitutes a significant physical risk to public or private property and no reasonable alternative to piping is available

32 Although the Respondent told the Court that DCP 47, adopted March 2004, superseded the 1993 Stormwater Management Manual, the supply of this latter information to the Applicant provided confusing and contradictory information with respect to the piping of watercourses.

33 In addition to the arguments surrounding the definition of the watercourse as per the WMA, the Council also contended that the development application was contrary to DCP 38, The Ku-ring-gai Residential Design Manual. The relevant aims of the DCP that relate to the application are provided in clause 1.2 and are as follows:

3. Conserve and protect the natural, built and cultural heritage significance of Ku-ring-gai, including heritage items and conservation areas, and encourage development which respects that significance.
4. Conserve and protect endangered species (flora an fauna), the natural topography, and other geographical and environmental features of Ku-ring-gai.
5. Achieve ecological sustainable development.
6. Ensure appropriate provision is made for drainage in order to minimise impact on neighbours, watercourses, trees and other elements of the built and natural environment.
7. Protect and minimise the impact of development on adjoining properties and the natural environment.

34 In addition there are a range of relevant objectives listed under clause 3.1, Environmental Constraints, in particular items a), b), c), f) and i). The assessment criteria 3.1.6, Natural Landscape, is also relevant since it requests that development applications shall not unreasonably intrude or impact upon natural features (inter alia) of the landscape and water courses.

35 With respect to the KPSO the Council noted that the following items under Schedule 9 were relevant:

1(a) to maintain and, where appropriate, improve the existing amenity and environmental character of residential zones; and
1(b) to permit new residential development only where it is compatible with the existing environmental character of the locality and has a sympathetic and harmonious relationship with adjoining development;
2(c) any building or development work shall maintain or encourage replacement of tree-cover whenever possible to ensure the predominant landscape quality of the Municipality is maintained and enhanced;

36 The Council’s Riparian Policy (2004) was also sited as a relevant consideration since it aims are (inter alia) to conserve, enhance and protect existing riparian corridors; prevent further piping and channelling of watercourses; and where possible reinstate existing piped or channelised watercourses to their natural form.

37 Finally, the Council also contended the application before the court was contrary to the Sydney Regional Environmental Plan No 20 – Hawkesbury-Nepean River (No 2-1997) (SREP 20), whose aims are to protect the aforementioned river system by ensuring that the impacts of future land uses are considered in a regional context.

Evidence and Findings

38 I had the benefit of two site visits, on the first of which (21st October 2008) I heard evidence from Mrs Clohessy of 24 Normurra Avenue, which is the property on the opposite side of the watercourse. She gave oral evidence that she had seen turtles in the creek and that previously there had been significant vegetation along the path of the watercourse.

39 On the second site visit I observed water flowing in the site’s channel, some small pools as well as other aquatic fauna in the form of an Eastern Water Dragon, Physignathus lesueurii on the eastern boundary fence of 27 Miowera Road. It is common knowledge that these lizards are often found by water, especially by creeks, river and lakes where there are overhanging branches or rocks that provide basking opportunities. These lizards have a diet that includes aquatic insects, terrestrial invertebrates and plant matter.

40 I was also able to observe areas of organic matter and inorganic sediment that had been moved recently following the preceding rains. Observations of the bed of the watercourse were obscured by the Applicant’s concrete pipe, which was already placed in the channel. However, I was able to observe natural bedrock outcrops at the downstream end of the pipe and also during the first site visit at the end of Mrs Clohessy’s garden. Despite the emplacement of the pipe, the channel form was clearly evident, in that there was a well-defined bed and banks.

41 Mr Tilly, the Applicant’s Geomorphologist expert contended in his written evidence (Exhibit B) that the watercourse bed and banks may have been artificially created along with the channel as an outlet for the upstream piped drainage network. Ms Findlay, the Council’s geomorphological expert agreed that the stormwater infrastructure has had an impact on the system but contended the watercourse channel was artificially modified rather than being artificially created. The original channel form was evident in the photographs submitted in Exhibit 1, Tab 9. These show vegetation (unidentifiable) along the path of the watercourse.

42 On the second site visit we were also taken to the downstream end of the system where the watercourse emerges from the piped sections close to Darri Track at the rear of Somerset Avenue. Here, I was shown grooves and small potholes in the Hawkesbury Sandstone bed of the watercourse by Ms Findlay. I was shown by Ms Findlay how the grooves extended underneath the concrete structure of the pipe system. This latter observation indicates that the erosion features are older than the stormwater pipe system. It was agreed generally by the expert geomorphologists that the features probably pre-date 1950. Although the age of the features are not precisely known, Ms Findlay stated relevantly (Exhibit 4):

“these features take hundreds of years to develop and indicate the presence of flows within this part of the landscape for many years.”

43 These erosion marks in the channel bed, are part of collection of features that form from water flowing over a hard, bedrock surface. I have observed similar features elsewhere in other watercourses (e.g. Gore and Taylor, 2003, Australian Journal of Earth Sciences, volume, 50, 467-470). Such features are referred to by geomorphologists as (inter alia) striations, flutes, grooves, scallops and potholes and their rate of formation is dependent on various hydraulic and hydrological factors including bedload transport (volume and size); frequency of run off, substrate hardness, discharge, velocity and water-bedrock chemistry interactions. Hawkesbury Sandstone is known to be a resilient material (hence its common use as a building material in Sydney). Consequently, it is likely that these features have formed over a considerable time period, one that at least predates the construction of the stormwater system. Notwithstanding a definite age, one must draw the conclusion from their presence that water flow of a reasonably regular and substantive nature has drained the upper parts of this small catchment for an extended timeframe.

44 In regard to the likelihood of water flowing in the specific area of the proposed development, the Applicant, in providing the Hornsby 1:25,000 maps (Exhibit E) enabled me to examine the nature contours of the land in the immediate vicinity. On both maps it is clear that the lowest point of the contours in the area pass directly through the Applicant’s property, in such a configuration to indicate that there is a natural drainage basin in this locality. The fact that no channel is marked here cannot be determinative because the land was highly urbanised when these maps were drawn and in any case, the ‘blue line’ on a map is a cartographer’s rather than a geomorphologist’s line. The drawing of a ‘blue line’ to indicate a river is not a scientific assessment (Taylor and Stokes, 2005a,b). Nevertheless, accepting the validity of a ‘blue line’ to indicate a river or stream, the eastern side of the catchment to the south, where similar contours exist in the absence of urban development, contain such a line.

45 In regard to the question of whether the watercourse has sufficient flow or otherwise for it to be defined as a river under the WMA, Mr Tilly undertook a water balance modeling exercise of the catchment using the MUSIC software and rainfall data for Turramurra (Bureau of Meteorology station 66158), which has a record of 65 years and an mean rainfall in excess of 1300 mm per annum. These results (Exhibit D), estimated that under the current developed (45 % impervious) catchment conditions that there would be flow in the channel 81.7 %, albeit with low flow volumes of < 1m3/day for an estimated 39.8 % of the time. He further calculated that for 73.7 % of the time daily flow volumes were < 1.2L/sec.

46 Mr Tilly also calculated flow conditions under natural, undisturbed conditions (0 % impervious). This modeling showed that there would be no runoff for 22.6 % of the time; daily runoff being < 1m3/day for 48.6 % of the time and estimated < 1.2L/sec for 83.5 % of the modeled 65 year time period.

47 The flow requirement for a river in the WMA is not quantified although Talbot J in Warringah Council v Ardel Limited and Anor [2000] NSWLEC 7 (25 January 2000) noted the following:

37. The Oxford Dictionary places significant emphasis on "a copious natural stream" and "a copious flow" , neither of which expressions could be applied to the subject site.
38. The statutory definition of a river is to be applied with due regard to common sense. It is not necessary to read the definition down in order to do this, at least for present purposes. A natural channel is one that is caused by nature so that it is inherent in the character of the land. The Court has not been satisfied that this criteria has been met. On the balance of probabilities, historically there may have been some flow through the site after heavy rain, but the Court cannot be satisfied that it would have generated the features of the present watercourse if council had not interfered with the natural discharge of stormwater, exacerbated by the industrial development across Aquatic Drive to the north.

48 I note however that these assessments were made when considering the definition of a river under the Rivers and Foreshores Improvement Act 1948, whose objectives were different as to the WMA. The aim of the WMA is to protect, enhance and restore the quality of water and its sources as well as to apply the principles of ecological sustainable development. Further, the definition of a river under part (b) of “rivers” in the Dictionary is a more inclusive definition in that it includes tributaries and branches or other watercourses that flow into or from watercourses that have perennial or intermittent flow occurring in a natural channel or a natural channel artificially improved.

49 In order to ascertain the naturalness of the channel at 27 Miowera Road, the Applicant provided a sequence of aerial photographs, the first of which was dated from the year 1930 (Exhibit F). This image showed a meandering feature running across the approximate area of the Applicant’s property. Due to the poor quality of the image it was not clear precisely what this feature was. It may have been a track as suggested by Mr Tilly (Exhibit 4). In response, Ms Findlay contended that the drainage easement across the property was not coincident with the watercourse and that it is a separate feature that has always been present. She further stated that the meandering, rather than straight, channel planform in Exhibit F indicates that the watercourse is most likely to be natural. In any case, the image was not clear enough to provide conclusive evidence on this matter.

50 The next image, dated 1951, was clear and showed without any disagreement between the parties that a channel and associated (riparian) vegetation was present in the vicinity of the Applicant’s property. The channel does not appear to be piped at this date. However, it does appear that this watercourse has been modified beyond 27 Miowera Road due to it having unnaturally straight sections of channel and it passing along property boundaries. This image is also not determinative as to whether the feature is a natural channel artificially modified or an artificial drainage channel.

51 However, the 1951 aerial photography does show that a watercourse was present in the area of the subject site. It is also an area where the contours of the land (Exhibit E) indicate there is likely to be a natural drainage basin if the catchment were not urbanised.

52 In addition, apart from the aerial photographs and the topographic contours on the 1: 25,000 maps, there is other significant evidence of the presence of a range of other river-related features. These include evidence for aquatic biota using the system; evidence of flow for 81.7 % of the time in the channel, albeit low volumes; evidence of natural sediment and erosion processes; evidence of bed and banks as far back as 1951 and evidence of riparian vegetation along the watercourse up until recently times, whereafter it was removed.

53 The court heard evidence from Mr Tilly and Ms Findlay about the source of the water. Both experts agreed that flow in the channel was sourced at least in part from soil through flow. Soil through flow is water that percolates through the interstices of the soil matrix. It seems to me that the source of the water is irrelevant to a large degree – what is relevant is that there is either flow or there is not as per Barwick CJ’s decision in Knezovic v Shire of Swan-Guildford. Base flow of creeks and rivers are often sourced by spring flow, which put simply is the surface expression of groundwater. Rainfall and surface runoff will also contribute to stream flow under certain conditions. However, some of this flow must also include, by virtue of gravity, rainfall’s recharge of groundwater systems, some of which is sourced from soil through flow.

54 Given that the base of the watercourse at 27 Miowera Road is comprised of bedrock and is perched above Cowan Creek, where the main groundwater recharge zone is likely to exist, it is highly probable that the presence of long-term flow in the channel is due to soil moisture recharge and its consequent through flow. Additional flow will be supplemented in wetter periods from overland flow and rainfall directly into the watercourse.

55 The geomorphological experts also considered the use by the NSW Department of Water and Energy (DWE) of the 20 ha guide to determine whether there is a likelihood of their being a natural channel present. This is an informal and non-statutory method because it does not take into account any special characteristics or circumstances. Perhaps more pertinently, the 20 ha rule does not take into account Part (b) of the WMA Dictionary definition of ”rivers” and significantly. In any event, the 20 ha rule appears to not have influenced the view of DWE who did not support the development application for piping at the subject site (Exhibit 1, Tab 5 and 6).

56 Mr Tilly and Ms Finday also considered the ‘9 part test’ (Exhibit 4) that was used by Taylor and Stokes (2005a,b) to assess the presence/absence of fluvial features that are usually present in a bona fide stream or river. Similar to the 20 ha rule and the ‘blue line’, these criteria are not prescriptive and are not statutory guidelines. Nevertheless Taylor and Stokes’ (2005a,b) ‘9 part test’ are considered here for completeness:

i) Are there definable channel banks and a channel bed?
Both experts agree that there are bed and banks and but differ in their view as to their origin. Mr Tilly contended the channel is an artificial system while Ms Findlay contends that it is a natural system, artificially modified. Exhibit 1, Tab 20) shows the presence of a well-formed channel at the site. The 1930 aerial photograph presented to the Court (Exhibit F) is inconclusive, although the meandering feature visible on this aerial photograph could be interpreted as the bed of a channel in the approximate location of 27 Miowera Road. This was Ms Findlay’s conclusion and I agree that this is the most likely explanation. The 1951 photograph is clearer and shows a channel and riparian vegetation. I accept this evidence and the current status that there is a channel with well-defined bed and banks, which undoubtedly has been altered markedly by urban runoff.
ii) Are there fluvial bedforms e.g. pools, riffles, sediment point bars etc and if so what are they?

Mr Tilly does states that the uneven bed form and any present in-channel features could have easily developed since the piped drainage system was constructed. At the site hearings, observations of the current channel were obscured by the pipe, which has been placed in the channel, pending the outcome of this hearing. Ms Findlay contended that photographic evidence prior to the imposition of the pipe coupled to the description of the channel in DA 440/04 for the adjoining property at 29 Miowera Road as having ‘pools and riffles’ is evidence that such features are characteristic of the subject watercourse. At the site visit, I observed small pools and sediment accumulation, indicating natural stream processes were operating in the watercourse.
iii) Is there any evidence for substantial erosion from water flow within the drainage feature?
Both experts stated that erosion was present in the channel and also at the site observations. It was evident that the channel was eroded down to bedrock at the subject site. Downstream of the subject site there was evidence of erosion in the form of grooves in the channel bed. At the site bank erosion along with the presence of the products of erosion – sediments and the like were also visible.
iv) Are there any spring lines that may indicate seasonally intermittent or perennial flow?
The experts agreed there were no spring lines. However, there was evidence from observations and hydrological modeling that flow persists in the channel for the majority of the time. The fact that the water is sourced from soil through flow as opposed to what is often thought of as spring flow (a geographically constrained point of resurgence) is irrelevant. It is irrelevant because of the fact there is water in the watercourse at least 81.7 % of the time, albeit in small volumes. Further, the definition of ‘spring’ from the online Oxford English Dictionary describes it as ( inter alia ):
2.a. A flow of water rising or issuing naturally out of the earth; a similar flow obtained by boring or other artificial means.
Thus, soil through flow must also be flow that is produced naturally out of the earth and could also be construed at least as a component of ‘spring flow’.
v) Is the catchment large enough to sustain perennial or intermittent groundwater flow?
Both experts agree that the catchment is too small for perennial or intermittent groundwater flow. Mr Tilly argues that the watercourse is totally dependent upon rainfall whereas Ms Findlay is of the view that the catchment is large enough to sustain intermittent or sub-surface flow. However, evidence presented to me demonstrates that the process of groundwater recharge is indeed occurring and that this is helping to sustain flow in the channel for 81.7 % of the time.
Soil through flow is a component of ground water recharge. In Don Burke and [16] Others v Hawkesbury City Council & Ors [2001] NSWLEC 222 (28 September 2001), Sheahan J, preferred the evidence of Dr Erskine who considered the role of ground water and soil flow in evaluating whether the watercourse was a waterbody or river. Sheahan J quotes Dr Erskine: [at para 71]:
“ there is insufficient groundwater or soil water flow to maintain a saturated drainage depression for any period of time.”
Dr Erskine in Don Burke refers to groundwater and soil through flow in the same sentence, implying that they can provide a common and unified source of flow in a river. Nevertheless, the finding in the Don Burke case is contrary to the flow modelled at the subject site. Evidence from the subject site in relation to this application shows that the processes of groundwater recharge via soil through flow is sufficient to maintain low levels of flow at least on an intermittent basis.
vi) Are there any indicators of prolonged wetness within the drainage feature?
Mr Tilly contended there were no features that indicated that there was evidence of prolonged wetness in the subject drainage line. Ms Findlay disagreed and stated that moss and riparian plant species ( Taro sp.) indicated that significant levels of moisture must be present to support these plants. Oral and written evidence from Mrs Clohessy was that hydrophilic (water-loving) animals (eels, frogs, lizards, turtles) had been seen in the creek over a number of years. Given the water flow modeling results of Mr Tilly, the presence of water-associated flora and fauna identified at the watercourse is not surprising.
vii) If surface flow is present, is it continuous and how extensive across the base of the drainage feature is it?
Mr Tilly stated that surface flow is not continually present in the system and that the drainage line is characterised by ephemeral flow rather than permanent or intermittent flow. His modeling shows that water flow is < 1m3/day for 39.8 % of the year with zero flow being present in the current system for an estimated 18.3 % of the 65 year modelled time period. Nevertheless Mr Tilly contended that the flow did not meet the ‘continuous flow’ criteria of Taylor and Stokes’ (2005a,b) ‘9 part test’. Ms Findlay agreed flow was not continuous but relied upon the modeling results that showed flow for around 80 % of the time. Observations at the on site inspection indicated that flow was low and was largely restricted to the central portion of the channel, but the experts noted that during wetter periods it was likely to fill the channel at the subject site to ~ 50 % of its bank top height. It is clear that flow is present in the watercourse for the majority of the time but the flow is not continuous and for ~ 40 % of the time period it is of a low volume.
viii) Are there any visible aquatic habitats that might sustain aquatic fauna?
Mr Tilly contended that there does not appear to aquatic habitat while Ms Findlay argued that a photograph of the site dated 31/03/06 (Exhibit 1, Tab 22) showed, various sedimentary deposits that are potential habitat for aquatic macroinvertebrates. In addition to the pools evident in the photographs, I was able to observe at the last on-site inspection the presence of standing water, which by itself would create habitat. However, the presence of hydrophilic animals at the site indicates that the watercourse sustains at least some aquatic life.
ix) Are there any aquatic flora present that would require periods of uninterrupted moisture?
Both experts agreed that there was no flora that required uninterrupted moisture. Ms Findlay contended that the Taro sp. would require significant, regular periods of moisture. The lack of channel bank vegetation and highly modified channel condition makes this difficult to assess. I note that in Exhibit 1, Tab 9, there is abundant vegetation along the watercourse, a matter that was also commented on by Mrs Clohessy in her evidence.

57 The information arising out of the application of the ‘9 part test’ would indicate that the applicant has not established that there is a preponderance of evidence to show that the watercourse at 27 Miowera Road is not a river.

58 On the balance of the evidence in tandem with the on site observations I am not satisfied that the watercourse in the property of 27 Miowera Road is not a watercourse. The definition provided in the WMA is constructed so as to be inclusive of all forms and types of watercourse. Given this finding, this means that this development application must be integrated development and that the requested works are a controlled activity, as per s 91 of the WMA.

59 Even if I am wrong in my interpretation of the watercourse and the application of the legislation are sufficient refuse the application as discussed below, the proposal is also contrary to a range of other relevant Council and State planning and policy documents. This is also sufficient to warrant rejection. Further, refusal of the development application would also be consistent with previous assessments of the watercourse and requests for associated works.

60 This development application does not have the support of DWE. The Department of Land and Water Conservation (DLWC) assessed an earlier Application DP376018 for the subject site and its watercourse and a Part 3A permit under the Rivers and Foreshore Improvement Act 1948 (RFIA) was granted. The permit was granted contingent special on conditions that a 5 m riparian zone was to be established along the watercourse.

61 This DLWC decision is consistent with that at the adjoining, downstream property at 29 Miowera Road, where the then consenting authority for a Part 3A permit, the Department of Natural Resources, granted permission for works (DP 227380) on the same watercourse. These works also included the establishment of a 5 m riparian zone measured horizontally from the top of the bank.

62 Therefore, to permit the piping of this section of watercourse as part of this development application would be contrary and inconsistent with previous assessments undertaken by the regulating authority at this site and at the adjoining property.

63 The Council contended that the development application was also contrary their Riparian Policy (2004). However, the Applicant demonstrated in exhibit L, an extract of the Riparian Policy Map, that the creek mapping and categorization exercise had not included the watercourse at the subject site. Ms Findlay noted that Council intends to include this section of channel in the map when the policy and map are revised in an upcoming review.

64 I do not see the inclusion or exclusion of a channel on the policy’s map as being determinative. Its completeness is limited by the fact that the majority of the data used to compile the map was derived from desktop studies, with some field verification. Rather, the objectives and intent of the policy are more significant as they establish clearly the purpose of this policy. In this regard, the development application is inconsistent with the aims and objectives of that policy.

65 The application is also inconsistent with DCP 47 and DCP 38, the aims, of which, put simply, are to protect, maintain and restore natural landscapes, including watercourses. In regards to the SREP 20, the impacts arising from the application are localised and while it is accepted that such impacts can be cumulative, this application does not in reality conflict in a significant way with the regional objectives of this planning instrument.

66 It is quite clear that the watercourse is already impacted heavily. The Council have recognized that many of its urban watercourses are similarly affected. In dealing with this issue, the Council have undertaken a substantial, broad-scale condition assessment of Ku-ring-gai’s creeks as well as the development of appropriate policy and planning tools to address and where possible reverse the deleterious impacts of urbanization on the catchment creeks systems. DCP 47 and the Riparian Policy are examples of this approach.

67 In addition, watercourses in Ku-ring-gai drain predominantly to larger receiving water sources in national parks, as is the case here. As a result, it is good management practice to protect, restore, maintain these systems while simultaneously mitigating any further negative impacts on watercourses and their riparian habitats. Such management objectives are synonymous with ecological sustainable development and the Objects and Principles of the WMA as well as DCP 47 and DCP 38.

68 The biodiversity value of degraded watercourses such as that at 27 Miowera Road are clearly compromised as noted by Mr Towle and Mr Wilks (Exhibit 5), the ecological experts for the Applicant and Respondent, respectively. Nevertheless, it is clear from the evidence in this case that they still provide habitat for a range of aquatic species and by inference, they must retain the potential to enhance and improve their habitat because they are demonstrably not sterile areas of biodiversity.

69 The applicant contended that the environmental impacts arising from the development would be minor (see McCellen CJ in BGP Properties Pty Limited v Lake Macquarie City Council [2004] NSWLEC 399 (12 August 2004) at para [114]) and that the benefits arising from piping the watercourse warrant its approval. The benefits that would arise were suggested to include improved water quality and safety for the owner and his family of 27 Miowera Road from flood hazards and dangers during storm events.

70 If the Applicant argues that the negative impacts on the system are minimal then so must be any benefits. The benefits of improved water quality were not readily obvious. Mr Wilks provided evidence in the joint ecologists report (Exhibit 5) that concrete pipes contribute to further increases in the alkalinity of runoff in a system naturally adjusted to a more acidic pH. Such changes to runoff water quality negatively impact aquatic and riparian organisms adapted to more acidic natural waters.

71 The Applicant contended the watercourse posed a risk especially when in flood. Mr Tilly noted (Exhibit B):

“ Under open channel conditions the channel and immediate verges are considered as being a high flood hazard category based on velocity and depth criteria as outlined in the NSW Floodplain Development Guidelines [2005].
Further the deep and high velocity flows carried by the channel represent a high hazard to occupiers and especially small children ”.

72 It would seem to me that a small pool type fence along with trees and bushes in the riparian zone could mitigate any dangers associated with a person falling into a channel running with water. Further, acknowledgement by Mr Tilly that water flows at rates and volumes that he considers dangerous is an admission that the system does in fact function like a watercourse. Consequently, it should therefore be afforded the appropriate level of protection as per the WMA and the various other relevant planning controls applied by the Council.

Conclusion

73 The evidence before me demonstrates that the watercourse at 27 Miowera Road is a natural feature artificially modified and is a ‘river’ as per the WMA. The watercourse has the appearance and functionality (physically and biologically) of a natural watercourse, artificially modified. It has either recently contained and still contains a range of aquatic fauna species. In addition, the evidence indicates that riparian vegetation once existed down the watercourse and that given suitable restoration techniques, it can be returned to its banks to provide additional and appropriate natural habitat. In regards to the merits of the application, the proposed piping of the watercourse does not accord with the principles of ecological sustainable development (Environmental Planning and Assessment Act, 1979, s 5) nor does it correspond to the Objects and Principles of the WMA or the Council’s DCP 38 or 47.

74 On the grounds stated above, the application for piping the watercourse is refused.

75 The orders of the Court are:

1. The appeal is dismissed;
2. Development Application DA0415/08 for consent to pipe the watercourse at 27 Miowera Road is determined by the refusal of development consent;
3. The exhibits are to be returned.

___________________

Dr M Taylor
Commissioner of the Court
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