Riverstone Parade Pty Limited v Blacktown City Council

Commissioners' judgment

1. The Commissioners' judgment identified the proposal for bulk earthworks and associated activities at [3]-[8]. Lot 211 has an area of about 228 ha and the site the subject of the appeal is the northern half of Lot 211. The proposal is described at [9]-[18]. According to the Statement of Environmental Effects - Version 2 (SEE), the proposed earthworks are limited to an activity area of approximately 60 ha, generally in the northern section of the precinct.
2. The SEE describes the proposal as the cutting, stockpiling and filling of part of the site to create a series of benches upon which future industrial development will occur. Approximately 1,400,000 m3 of on-site material is proposed to be cut from the higher northern portion of the site to be used to fill low lying areas in the southern and central portions. Another 125,000 m3 of excavated natural material (ENM) is to be sourced from projects such as the construction of the North West Rail Link.
3. The contentions of the Respondent, Blacktown City Council (the Council), identified unsatisfactory impacts on the floodplain (contention 1) and the precedent and cumulative impact - impacts of filling on floodplain (contention 2) at [20].
4. Planning controls were identified at [22]-[46] including the State Environmental Planning Policy (Sydney Regional Growth Centres) 2006 (the SEPP) and the Riverstone West Development Control Plan 2009 (the DCP). The judgment can be extracted as follows: Planning controls 22 State Environmental Planning Policy (Sydney Regional Growth Centres) 2006 (SEPP - SRGC) applies. The SEPP was amended in 2009 by amending instrument State Environmental Planning Policy (Sydney Regional Growth Centres) Amendment (Riverstone West Precinct) 2009. The aims of the policy (in conjunction with amendments to the regulations under the Act relating to precinct planning) include: (a) to co-ordinate the release of land for residential, employment and other urban development in the North West and South West growth centres of the Sydney Region; [(b) to enable the Minister from time to time to designate land in those growth centres as ready for release for development,] (c) to provide for comprehensive planning for those growth centres, [(f) to provide for the orderly and economic provision of infrastructure in and to those growth centres,] 23 Clause 20 SEPP - SRGC applies to 'Development on and near land at Riverstone West'. It states: (1) This clause applies to the land outlined in red on the North West Growth Centre Development Control Map. (2) Despite any other provision of this Policy (including any Precinct Plan), the consent authority must not grant consent for development on land to which this clause applies unless it is satisfied that the proposed development: (a) will be undertaken in a manner that is consistent with the Floodplain Management Strategy (being part of the Riverstone West Precinct Development Control Plan), and (b) does not increase flood levels on adjoining properties in events up to the design 100 year recurrence flood, and (c) limits any increases in flood velocities on adjoining properties in events up to the design 100 year recurrence flood to minor increases only, and (d) is not likely to result in adverse flood impacts on adjoining properties (including during the construction stage of the proposed development). (3) This clause does not apply to development that the consent authority is satisfied is minor and will not result in unacceptable adverse flood impacts on adjoining properties. … 26 Of relevance is Riverstone West Development Control Plan 2009 (RWDCP) prepared by the Department of Planning in 2009. It is assumed that this DCP applies as it is called up in cl. 20(2)(a) SEPP-SRGC, … 27 Amongst other things, the purpose of RWDCP is to "consolidate and simplify the planning controls to ensure the orderly, efficient and environmentally sensitive development of the Riverstone West Precinct as envisaged by the North West Growth Centre Structure Plan, State Environmental Planning Policy (Sydney Regional Growth Centres) 2006…and as refined by the Riverstone West Indicative Layout Plan" (s 1.2.2). 28 Section 1.7.1 RWDCP sets out the development assessment process. Step 2 requires an applicant to prepare relevant Precinct-wide plans/ strategies identified in the table in s 1.7.3. Section 1.7.2 allows variations to development controls providing the applicant can demonstrate that the proposed development is consistent with the vision and development objectives for the precinct as well as the relevant objectives and controls in SEPP-SRGC. 29 Unusually, the table in s 1.7.3 does not indicate a requirement for a precinct-wide Cut and Fill Plan for earthworks development applications. 30 Section 1.7.3 goes on to provide the specific requirements for all precinct wide plans and strategies that must be submitted with a DA. Relevantly, and amongst others, a Floodplain Management Strategy (FMS) and an Integrated Water Management Strategy are required. 31 In regards to the FMS, the DCP states: The Floodplain Management Strategy (FMS) must comply with the requirements of Appendix C in this DCP. … 32 Section 2.2 Development Objectives, relevantly states: The development objectives of Riverstone West are to [amongst other things]: 1) Maximise employment opportunities within Riverstone West for the local and regional communities 2) Ensure development does not cause any offsite flood impacts that are unacceptable to Council. … 34 RWDCP Appendix C - Floodplain Management Strategy is therefore relevant. This appendix outlines the specific requirements for the preparation of an FMS. The appendix states: The land to which this strategy applies (the Subject Land) is Lot 211 DP 8300505 (located within the Riverstone West Precinct) and [emphasis added] Lot 11 DP 816720 Riverstone Parade, Riverstone located immediately to the west of the Precinct (refer Figure C). 35 The objectives of Appendix C are to: 1) Define exiting flooding at the site and in the vicinity of the site in accordance with the NSW Floodplain Development Manual, 2005, the Growth Centres Development Code and Council procedures 2) Determine the flood impacts on account of the proposed development, and investigate mitigation options which will input into the Floodplain Management Strategy 3) Develop a strategy that demonstrates flood impacts at the site and adjoining the site are managed in accordance with the requirements of the Growth Centres SEPP Amendment (Riverstone West Precinct) 2009, the Growth Centres Development Code and the development controls in Section 4.3 of this DCP 4) Ensure that the Floodplain Management Strategy is supported by a Flood Emergency Response Plan and a Cut and Fill plan [emphasis added] 5) Ensure that the Floodplain Management Strategy addresses the specific requirements listed in Strategy Formulation Requirements in the Appendix of this DCP. 36 Amongst other things, the Strategy Formulation Requirements 2, 3 and 4 require studies of a wide range of possible flood events including as a minimum the 2 year ARI, 5 year ARI, 20 year ARI, 100 year ARI, 200 year ARI (approximate HHF [defined as the highest historical backwater flood recorded in the Hawkesbury/Nepean Catchment, being the 1867 flood with a recorded level of 19.7 m AHD or 2.4 m above the current 100 year backwater level of 17.3 m AHD for that catchment]), 500 year ARI and PMF [probable maximum flood - the largest flood that could conceivably occur at a particular location] events. In addition, the flood studies are to consider backwater flooding from the Hawkesbury River, flooding of Eastern Creek and any relevant tributaries. The requirements specify the combination of flooding events to be investigated. … 43 While the table in s 1.7.3 of RWDCP does not indicate a requirement for a Cut and Fill Plan for precinct-wide earthworks development applications, objective 4 in Appendix 3 [Flood Management Strategy] requires that the Floodplain Management Strategy to be prepared by an applicant be supported by a Flood Emergency Response Plan and a Cut and Fill Plan. 44 The objectives and controls for cut and fill are found in Section 4 of the DCP - Environmental Management under s 4.2 - Cut and Fill. Relevantly the objectives of cut and fill are to: provide a platform capable of supporting a range of business and industrial uses; minimise the impacts of earthworks on stormwater salinity and groundwater; manage flooding impacts in accordance with the requirements of the Growth Centres SEPP Amendment (Riverstone West Precinct) 2009; and ensure that any cut and fill does not adversely affect the conservation and rehabilitation of the riparian corridors. 45 In regards to the controls, they include: 1) A Cut and Fill Plan must be prepared in accordance with Table 4 in Section 1.7.3 [This is not specified in Table 4] 2) Earthworks within the Subject Land (as shown in Figure C1 of Appendix C Floodplain Management Strategy of this DCP) are to be undertaken to achieve a balance between cut and fill in accordance with the Floodplain Management Strategy (FMS) as described in Appendix C of this DCP. The FMS will confirm the final Cut and Fill Plan, which is based on the Preliminary Cut and Fill diagram shown in Figure C2 of Appendix C. 3) The finished earthworks levels are to be generally in accordance with the Preliminary Cut and Fill contours shown in Figure C3 of Appendix C. The FMS will confirm the final cut and fill levels. 8) Earthworks associated with filling within the Precinct may be undertaken in accordance with the Staging Plan as required in Appendix C. DAs are to be lodged for each stage of the earthworks, and shall be supported by documentation that demonstrates conformance with the requirements of Appendix C. 10) The Staging Plan in the Floodplain Management Strategy must be updated if there is a deviation from the most recent staging plan in Appendix C. 11) Minimum cut and fill levels must comply with Figure 20. The slope between the designated levels shall be a maximum of three per cent.
5. The evidence of the various flood experts Mr Thomas (for the Appellant), Mr Bewsher and Mr Hardwick Jones (both for the Council) is identified at [47]-[74] and is partially extracted below: 57 The basis of the assessment is the 1:100 year flood level of RL 17.3 mAHD. 58 Amongst other things, the experts considered the FMS. The joint report outlines the potential fill options for the Riverstone West Precinct considered in the FMS. ∙ Option 1 is based on the maximum fill extent defined by the Indicative Layout Plan [Figure 5 RWDCP] approved as part of the rezoning of Lot 211. It involves no cut within Lot 211 and the net loss of floodplain storage below 17.3 mAHD of 3.62M m3. ∙ Option 2 is based on the same layout plan as Option 1 but considers floodway constraints and selective cut within Lot 211. It results in a net loss of floodplain storage below 17.3 mAHD of 3.74 M m3. ∙ Modified Option 2 [considered during conciliation] involves selective cut within Lot 211 and a net loss of floodplain storage below 17.3 mAHD of 2.65M m3. This is the option assessed in the FIA - referred to in that document as the "updated development layout". 59 The FMS modelled the combined probabilities of concurrent flood events required by the RWDCP: Eastern Creek 100 year ARI + Hawkesbury 100 year ARI; Eastern Creek 100 year ARI + Hawkesbury 5 year ARI; and Eastern Creek 100 year ARI with no concurrent flooding of the Hawkesbury. In addition, for completeness, Worley Parsons modelled a combination of a 100 year ARI Eastern Creek flood with a 20 year ARI Hawkesbury flood for option 1. … 64 Notwithstanding the limitations of the models, all three experts agree that the modelling undertaken for the FMS and the FIA appears reliable and provides accurate estimates of the impact of the proposed development on flood levels and velocities under local flooding conditions. They agree that the changes in flood velocities due to the three options are likely to be small and consistent with cl. 20(2)(c) of SEPP-SRGC (Exhibit 9- [13]-[14]). 65 The joint report includes a number of tables summarising the predicted maximum rise in flood levels for both local and regional flooding derived from the three models used for the range of flood events given in paragraph 59. … 70 With respect to regional flood levels, all three experts agree there will be an increase as a consequence of the proposed development. The increase in levels for option 1 is agreed at no more than 12mm; for modified option 2, the experts consider the range is from 5mm to 9mm.
6. The parties' submissions were summarised at [75]-[90]. At [75]-[80], [86] and [88]-[90] the Commissioners stated: 75 The applicant contends that in view of the strategic aims of SEPP - SRGC, the Court should take a purposive approach in considering cl. 20(2) of SEPP-SRGC. 76 Mr Clay, for the applicant, asserts there are different standards applied to the relevant sub clauses (2)(b), (c), and (d). In addition, cl. 20(3) identifies another standard. Specifically, cl. 20(2)(b) states "does not increase", cl. 20(2)(c) limits any increases to "minor increases", and cl. 20(2)(d) states the proposed development must not result in "adverse" flood impacts. Clause 20(3) considers minor development that will not result in "unacceptable adverse" flood impacts. 77 In Mr Clay's submission, the key question to be answered is - what is the proper construction of the phrase in cl. 20(2)(b) -"does not increase flood levels". It is his submission that this phrase means an increase in flood levels which is more than nominal, not trivial, not negligible and therefore material. He cites a number of cases to support this contention including Dainford v Lamb (1985) 3 NSWLER 255 at [268] where Powell J said in considering the phrase "affected substantially and adversely": By adding the word 'substantially' to a clause which would otherwise be operated if the relevant effect was anything more than just nominal, the draftsman was intending to indicate that, before the clause could operate, the relevant effect must be shown to be of real substance. In Manning v Bathurst Regional Council & Others (No 2) [2013] NSWLEC 186, Pepper J at [63] and [71] in regards to the meaning of unlikely to be affected" said: [63] … In other words, 'affect' is not to be construed to include any and all 'effects' no matter how trivial, of a development … [71] … The only applicable touchstone is one of materiality, or conversely, immateriality or triviality … 78 In regards to the application of cl. 20(2)(b) to the expert evidence, Mr Clay maintains that this only applies to adjoining properties and not to the broader region and that the agreed position of the experts was that the increase would be about 10mm which falls within the accuracy limits of the flood models. To that extent, the increase must be considered negligible or immaterial and therefore cl. 20(2)(b) is not offended and cl. 20(2)(d) is met. With respect to cl. 20(2)(c), the experts agree that the increase in velocity is likely to be minor and acceptable. While he agrees that the development is more than minor, Mr Clay asserts that the performance outcome of "will not result in unacceptable adverse flood impacts on adjoining properties" in cl. 20(3) is achieved by this proposal. In regards to the 100/20 combination of flood events and a possible increase of 40mm, Mr Clay maintains that the Court should accept Mr Thomas' evidence on the unlikely occurrence of such an event. He submits there is no evidence that this combination should be considered as the design flood level, which he asserts, is Mr Bewsher's view. 79 Mr Clay maintains that while cl 20(2)(a) requires the proposed development be undertaken in a manner consistent with the Floodplain Management Strategy in RWDCP, this implies broad compliance and a common sense approach that achieves the desires outcomes of the SEPP and DCP. To that end, the proposed cut and fill volumes should be based broadly on the relevant figures in Appendix C of RWDCP. 80 With respect to the regional flooding impacts of the proposal, Mr Clay contends that this is effectively a diversion as the DCP expects there to be some regional impact as it allows fill within the floodplain. He asserts that the emphasis in the SEPP and the DCP is on local flooding and there is no requirement to consider the cumulative regional impacts. Mr Clay maintains the context must be the regional/strategic level set by the creation of a growth centre and any impacts must be offset against regional and broader community benefits. He contends that the regional impacts of adding 2.65M m3 to a floodplain in excess of 22,000 km2 would have the equivalent impact of adding a few grains of sand to a glass of water. … 86 In regards to cl. 20(2) SEPP-SRGC Mr Miller contends that: subclause (a) is capable of being achieved however the development application falls short; as subclause (b) is not satisfied, the Court must not approve the DA; as any increase in velocity of floodwaters is agreed by the experts as being minor, subclause (c) is met; subclause (d) doesn't specify flood levels and requires consideration of the construction stage, as the applicant has not modelled the impacts of the cut and fill proposed in the DA, satisfaction of this subclause is uncertain. … 88 Council's view is that the development application is deficient in many ways as it does not fully meet the requirements of RWDCP. This includes: no modelling of any fill below the 17.3 mAHD level; no investigation of the impacts of the staging of the earthworks on flood level, and in particular, the impact of the earthworks the subject of the DA; and no current stormwater plan. 89 Mr Miller maintains that any suggestion that the DCP permits flood impacts is incorrect and elevates the DCP above the SEPP. 90 In regards to the regional flooding impacts and associated potential damages, Mr Miller contends that this is not a distraction and council's concerns are entirely reasonable and responsible and the issue is an important matter for consideration under s 79C.
7. At [91]-[106] the Commissioners outline their reasoning and findings: Consideration and findings 91 The main issue in these proceedings is the impact of the net increase in fill and subsequent loss of flood storage as a consequence of the proposed earthworks on local and regional flood levels. 92 Section 79C of the EPA Act requires us to take a number of relevant matters into consideration in our determination of this development application. 93 The starting point of our consideration must be SEPP-SRGC as this is the environmental planning instrument that applies to the site (s 79C(1)(a)(i)). Essentially, the aims of the SEPP are to co-ordinate the release and planning of land for urban development in an orderly and sustainable manner in Sydney's regional growth centres, including the North West Growth Centre. 94 Clause 20 - Development on and near certain land at Riverstone West -specifically applies to this development application. Clause 20(2) makes it clear that "Despite any other provision of this Policy" (including any Precinct Plan), the consent authority must not grant consent for development on land to which this clause applies unless it is satisfied of all four specified matters in subclauses (a), (b), (c) and (d). 95 Subclause 20(2)(a) requires that the proposed development will be undertaken in a manner that is consistent with the Floodplain Management Strategy which is part of the RWDCP [Appendix C]. Therefore, the SEPP requires the application of the DCP. Notwithstanding the deficiencies in RWDCP (discussed elsewhere), the DCP in turn consistently requires demonstration of compliance with the SEPP. Apart from the exceptions noted below, we are generally satisfied that the applicant's detailed Floodplain Management Strategy, to the extent that this underpins the proposed development, complies with Appendix C of RWDCP. We acknowledge the applicant's acceptance of the deficiencies in the Development Application and council's agreement that most of these deficiencies can be dealt with by way of conditions. 96 In our view, subclause 20(2)(b) is the key to whether consent can be granted to the proposed development. This subclause requires the consent authority to reach a state of satisfaction that the proposed development 'does not increase flood levels on adjoining properties up to the design 100 year recurrence flood'. 97 In this regard we prefer Mr Miller's submissions on the interpretation of the subclause (at [85]). In our view 'does not increase' has the same meaning as 'there will be no increase'. The ordinary meaning of 'no' (Macquarie Dictionary) in this context is "not in any degree", and for 'not'- "a word expressing negation, denial, refusal or prohibition". In our view, this subclause prohibits any development that would lead to an increase in flood levels on adjoining properties. There is no qualification of the word 'increase' other than a prohibition through the use of 'not'. This is contrasted with the qualifications of the degree of flooding or level of impact allowed in subclauses (c) and (d). 98 At [17] of the joint report, and confirmed in oral evidence, the experts agree that the proposed development will increase flood levels outside Lot 211 and therefore on adjoining properties; albeit the increase is less than 10mm for most modelled flood scenarios, a figure acknowledged to be within the sensitivities of the models. While we note the dispute between the experts about the 100 year ARI Hawkesbury flood with a 20 year ARI Eastern Creek flood and its significance, the potential increase of this combination is 40mm. Even if we accept Mr Thomas' considered and reasonable explanation of the rarity of this event and discard this combination, as there will be an increase in flood levels arising from the other modelled events, we cannot grant consent to the development application before us. 99 We also note the agreement between Mr Bewsher and Mr Thomas at paragraph [69] of this judgment that refining the fill footprint in the south-east corner of Lot 211 would probably reduce the predicted flood level for the 100/20 combination to an acceptable level, no modelling has been undertaken to demonstrate whether that acceptable level is still an increase, and or what the impact may be on the other specified combinations of flood events. Therefore, despite this agreement, we cannot be satisfied to the level required by cl. 20(2). 100 While modelling has been undertaken for the design 100 year recurrence flood, but not specifically up to that point as required by c. 20(2)(b), we do not see this particular element of the subclause as a matter warranting refusal. 101 Although we have determined that we cannot grant consent to the proposed development, we have considered the other subclauses and matters to be addressed under s 79C. 102 As the experts agree that the proposal limits any increases in flood velocities on adjoining properties to minor increases, we are satisfied that subclause 20(2)(c) is met. 103 On the face of it, the increases in flood levels on adjoining properties appear to be small however, as no modelling has been undertaken of the proposed stage 1 earthworks, we cannot be satisfied there will be any adverse flood impacts on those properties as a consequence of the proposed development. To this end, subclause 20(2)(d) is not met but could be with further modelling and assessment. 104 In regards to the regional impacts, the focus of cl 20(2) is on adjoining land and therefore local impacts. RWDCP appears to have a broader, more ambiguous focus. While Appendix C requires an FMS to consider local impacts, it must also be prepared in accordance with the NSW Floodplain Development Manual 2005. The Manual does not specify the size of any study area however it provides a range of factors to consider in defining the study area. The Worley Parsons FMS considered it unrealistic to consider the entirety of the Hawkesbury-Nepean system given its massive size. The FMS investigated the impact on an area of about 98km2 being the 'local' floodplain with a consistent 100 year ARI flood level equivalent to 17.3 mAHD'. In our view this is a reasonable approach. 105 Notwithstanding the disagreement between Mr Thomas and Mr Bewsher about the assessment of the cumulative impacts of the proposal on the floodplain, we note the experts' agreement (paragraph [70] of this judgment) that there will be an increase in flood levels at a more regional level. While this is a relatively minor increase, it will nonetheless have an economic impact and must be considered in the public interest under s 79C(1)(e). The SEPP provides no specific guidance in regards to regional impacts although applying the same logic to regional flooding as is given to local flooding in cl. 20(2)(b), we must similarly refuse the proposal on this basis. We also note the Development Objective (2) in RWDCP which is to "ensure development does not cause offsite flood impacts that are unacceptable to Council". On the evidence before us we cannot be satisfied that the offsite flood impacts would be acceptable. 106 Both the SEPP and s 79C(1)(a)(iii) require consideration of RWDCP.

Evidence

1. The Appellant tendered an appeal court book comprising four volumes (exhibit A) made up of, inter alia, relevant planning instruments, transcripts, exhibits and the Council's contentions at first instance. The Appellant's expert evidence included the Flood Impact Assessment (FIA) and Flood Management Strategy (FMS) of Mr Thomas, hydrologist, both dated 19 September 2014 and the Statement of Environmental Effects dated September 2014 prepared by Mr Grech, town planner. The Council's expert evidence included floodplain development advice dated 19 November 2014 prepared by Mr Bewsher, hydrological and flooding expert, and a modelling and impact assessment prepared by WMAwater dated 4 December 2014. Mr Hardwick Jones was the principal author of the WMAwater report, the modelling for which was conducted by Mr Parsons. Also before the Commissioners was a joint expert report on flooding dated 9 December 2014 prepared by Mr Thomas, Mr Bewsher and Mr Hardwick Jones.

Grounds of appeal

1. The Appellant stated that the various grounds of appeal could be grouped into three areas and that is how they are considered below.
2. The Council submitted that none of the alleged errors were vitiating as the Commissioners also resolved at [105] that the application should be refused under s 79C(1)(e) of the Environmental Planning and Assessment Act 1979 (NSW) (the EPA Act) and there is no challenge to that finding in this appeal. The Appellant submitted that s 79C was considered through the lens of the SEPP and the DCP and there was no freestanding s 79C determination. That the Commissioners separately considered s 79C(1)(e) and refused consent on the basis of that subsection is clear when [85], [90], [92], [101] and [105] are read, suggesting the Council's submission is correct. The Commissioners' approach is supported by the terms of s 79C(1) and was the approach adopted in Hub Action Group Incorporated v Minister for Planning [2008] NSWLEC 116; (2008) 161 LGERA 136. I will nevertheless consider the grounds of appeal.

Issue 1 - construction of cl 20(2)(b)

1. In respect of cl 20(2)(b) of the SEPP, three grounds of appeal are advanced: 1. The Court erred in its construction of clause 20(2)(b) of State Environmental Planning Policy (Sydney Regional Growth Centres) 2006 ("the SEPP") in failing to hold that on its proper construction "no increase" means "no material increase" or "no increase other than a negligible increase" and therefore applied the wrong test to the question of compliance with clause 20(2)(b). 1A. In finding that, for the purposes of cl.20(2)(b) of the SEPP, the carrying out of the proposed development would result in an increase in flood levels on adjoining properties the Court erred in law as, on the evidence before the Court, properly considered, there was no evidence to support the finding, or alternatively the facts before the Court were incapable of justifying that finding either directly or by inference. 4. Insofar as it may have formed part of the Court's reasons for refusal, in making the finding at [99] that there was no modelling of the potential amendment referred to in the experts' agreement, the Court failed to afford the Applicant procedural fairness in not giving the Applicant the opportunity to do that modelling.

Ground 1 - construction of subclause (b)

1. The Appellant submitted that the Commissioners erred at [97] in finding that "does not increase" meant "there will be no increase". First, the Commissioners ignored the only authority cited (Macquarie Dictionary) on the question on the proper construction of verbs of the same character as "increase". In the course of recounting the Appellant's submissions at first instance, reference was made to Dainford Ltd v Lamb (1985) 3 NSWLR 255 at 268 and Manning v Bathurst Regional Council (No 2) [2013] NSWLEC 186; (2013) 199 LGERA 147 at [63], [71] as supporting the position that an "increase [in] flood levels" for the purpose of subclause (b) "means an increase in flood levels which is more than nominal, not trivial, not negligible and therefore material" (judgment at [77]). However, no attempt was made to reconcile those decisions with the Commissioners holding contrary to the Appellant's submission (see judgment at [97]).
2. Second, the Commissioners failed to consider the maxim de minimis non curat lex ("the law does not concern itself with trifling matters"). This principle, which applies to questions of construction generally, addresses the scenario in which a provision may be read to allow minor departure from, for example, a prohibition: see Farnell Electronic Components Pty Ltd v Collector of Customs (1996) 72 FCR 125 at 130 per Hill J. The applicability or otherwise of the de minimis maxim depends upon the context in which it falls to be considered: see Farnell at 130. In this regard it is significant to reiterate that the language of subclause (b) is "does not increase", not (as the Commissioners paraphrased it) "there will be no increase". The Commissioners' reliance on the Macquarie Dictionary definition of "no" as meaning strictly "not in any degree" at [97] is thus not directly to the point. The proper question for the Commissioners was whether the phrase "does not increase" should be read as an absolute standard.
3. Clause 20(2)(b) is a proper candidate for the application of the de minimis maxim since an increase in flood levels (as a result of proposed development) can vary greatly - it can range from the trivial to the very substantial. A development application would properly be refused in the latter scenario, but not in the former. However, in failing to acknowledge this issue, the Commissioners made an error of law in requiring perfect compliance where the language of subclause (b) did not suggest or require an exclusion of the operation of the de minimis maxim.
4. Third, the Commissioners gave undue weight to the text of other subclauses of cl 20(2) and insufficient weight to the purpose of the SEPP. The Council's submissions at first instance, which the Commissioners preferred, were to the effect that subclauses (b) should be applied strictly on its terms because its text was to be contrasted with the qualifications in subclauses (c) and (d), which respectively deal with "minor increases" in flood velocities and "adverse flood impacts" (see judgment at [87], [97]).
5. Considering cl 20(2), subclause (b) if construed without allowance for trivial or negligible increases in flood levels on a de minimis basis, is out of step with subclauses (c) and (d), and cl 20(3), which contain qualifications allowing for the consent authority to consider degree of the "increases" or "impacts" that would result from proposed development. That is a reason not to construe subclause (b) with utmost strictness. Indeed, a relevant textual conflict for the purposes of Project Blue Sky Inc v Australian Broadcasting Authority [1998] HCA 28; (1998) 194 CLR 355 arises if perfect compliance is required on only one of the relevant flooding issues which cl 20(2) addresses.
6. In that respect, assistance regarding the "purpose" of the provisions of the SEPP is provided in cl 2 which expressly states the "Aims of Policy". It is apparent from that clause that key objectives of the SEPP are to encourage "residential, employment and urban development" in the designated "growth centres" (cl 2(a)), to allow the land to be "release[d] for development" (cl 2(b)), and "to provide for the orderly and economic provision of infrastructure in and to those growth centres" (cl 2(f)).

Finding on ground 1

1. The first ground requires the statutory construction of cl 20 in the SEPP. The Appellant relied on the well-known principles in Project Blue Sky at 381-382 [69]-[70] per McHugh, Gummow, Kirby and Hayne JJ (footnotes omitted): 69 The primary object of statutory construction is to construe the relevant provision so that it is consistent with the language and purpose of all the provisions of the statute. The meaning of the provision must be determined "by reference to the language of the instrument viewed as a whole". In Commissioner for Railways (NSW) v Agalianos, Dixon CJ pointed out that "the context, the general purpose and policy of a provision and its consistency and fairness are surer guides to its meaning than the logic with which it is constructed". Thus, the process of construction must always begin by examining the context of the provision that is being construed. 70 A legislative instrument must be construed on the prima facie basis that its provisions are intended to give effect to harmonious goals. Where conflict appears to arise from the language of particular provisions, the conflict must be alleviated, so far as possible, by adjusting the meaning of the competing provisions to achieve that result which will best give effect to the purpose and language of those provisions while maintaining the unity of all the statutory provisions. Reconciling conflicting provisions will often require the court "to determine which is the leading provision and which the subordinate provision, and which must give way to the other". Only by determining the hierarchy of the provisions will it be possible in many cases to give each provision the meaning which best gives effect to its purpose and language while maintaining the unity of the statutory scheme.
2. Clause 20(2) of the SEPP states that consent must not be granted for development unless a consent authority is satisfied of the matters in subclauses (a)-(d). At issue in this ground is the construction and application of subclause (b) which states "[development] does not increase flood levels on adjoining properties in events up to the design 100 year recurrence flood". "Adjoining properties" and "design 100 year recurrence flood" are not defined in the SEPP. At [97] the Commissioners held that "does not increase" means precisely as it states. At [98] the Commissioners identified that the experts agreed that the proposed development would increase flood levels outside Lot 211 and therefore adjoining properties. At issue is the meaning of "does not increase".
3. The Appellant adopts an overly critical approach to the wording of the judgment in [97] contrary to the principles articulated in Brimbella Pty Ltd v Mosman Municipal Council (1985) 79 LGERA 367 at 368 cited in many subsequent authorities. Whether couched in the terms used by the Commissioners or as whether compliance with an absolute standard is required by the statute according to the Appellant, no legal error in reasoning is disclosed by the Commissioners' adoption of the Macquarie Dictionary definition of "no".
4. The Appellant's contentions at first instance on the meaning of cl 20(2)(b) were summarised at [76]-[78] of the Commissioners' judgment. Reliance was placed on Dainford Ltd v Lamb considering "affected substantially and adversely" and Manning v Bathurst Regional Council (No 2) considering "unlikely to be affected" as supporting a contention that "does not increase flood levels" means "an increase in flood levels which is more than nominal, not trivial". As the Council submitted, those authorities provide no assistance given the different statutory framework and statutory terms considered therein. "Increase" cannot be equated with "affect".
5. As the Appellant accepted relying on Farnell at 130, whether a statutory phrase in absolute terms should be so construed depends on the context in which it is to be considered, as cited in DC Pearce and RS Geddes, Statutory Interpretation in Australia, (8th ed 2014, LexisNexis Butterworths) at [4.22]. The Appellant submitted that because flood levels can vary greatly ranging from very small to very large (a matter of fact), and that a development application would be refused in the latter not the former (an assertion), subclause (b) should be read in a qualified not absolute manner. No question of statutory construction or failure to apply the de minimis maxim arises from these general submissions referring to matters of fact. It is not self-evident from the statutory scheme that "does not increase" in subclause (b) should be read as qualified by "trivial or minor".
6. The third contention is that the Commissioners gave undue weight to other subclauses of cl 20(2) and insufficient weight to the purpose of the SEPP. The Commissioners accepted the Council's submissions on the construction of subclause (b) read in the context of the other subclauses of cl 20(2). I agree with the Council's submissions on this aspect of this ground as follows. Legal meaning will usually correspond with the grammatical meaning per Project Blue Sky at [78]. Giving effect to harmonious goals in the SEPP does not mean that the qualifying words in subclause (c) or (d) of minor or adverse should be implied in subclause (b). Subclause (b) addresses flood levels. Other subclauses are directed to flood velocities (subclause (c)) and flood impacts (subclause (d)). Subclause (b) can be read in a manner which does not require additional words to be read into it and give effect to subclauses (c) and (d). Such a reading of subclause (b) is not out of step with the other subclauses and does not result in a textual conflict contemplated in Project Blue Sky at [70]. This approach to construing cl 20(2) is consistent with the principles identified in Project Blue Sky at [69] and [70] set out above.
7. There is no absurdity in the Commissioners' finding that "does not increase" means "there will be no increase". That the aims of the SEPP includes the coordination of broad categories of development in growth centres (cl 2(a)), the release of land for development (cl 2(b)) and the orderly and economic provision of infrastructure in growth centres (cl 2(f)) does not undermine this approach to construction. As identified in the Council's submissions, the SEPP applies to large areas of land intended for development as growth centres.
8. This ground of appeal fails.

Ground 1A - challenge to finding on evidence

1. The Appellant also submitted that the Commissioners erred in finding the proposed development would result in an increase in flood levels on adjoining properties in the absence of evidence or facts supporting such a finding. The basis of the Commissioners' decision was an apparent consensus between the expert witnesses as to the fact of an increase in flood levels on three particular modelled scenarios. However, the increases in each scenario were within the range of tolerance or accuracy of the model used. The modelled "increase", viewed within the tolerance of the model results, actually is no increase. The relevant evidence was recorded as follows (see judgment at [66], emphasis added by Appellant): Mr Bewsher and Mr Thomas agree that the results of the modelling of the three local flood scenarios required by RWDCP indicate that there will be an increase in peak flood level outside Lot 211 of less than 10mm. … It is agreed that the accuracies of flood models are traditionally considered to be 10 to 20mm.
2. In other words, the expert witnesses effectively agreed that the model was not sensitive enough to predict one way or another whether there would in fact be an increase in flood levels.
3. The facts before the Commissioners therefore, properly viewed, were that no agreed scenario gave a result exceeding the sensitivity of the model. The Commissioners' view that there was an increase was therefore contrary to that agreed fact, and was a finding in the absence of fact. As such it was an error of law: Tuite v Wingecarribee Shire Council (No 2) [2008] NSWLEC 321 at [76] and the authorities therein cited. The Commissioners then appear to have considered their hands were tied: "we cannot grant consent to the development application before us" (see judgment at [98]), giving rise to the result on this issue.

Finding on ground 1A

1. This ground of appeal purports to identify a question of law framed as a finding by the Commissioners allegedly made without evidence. The issue identified however is really a question of fact which should be determined by the expert evidence at the hearing. The ground essentially relies on the application of what is said to be the plain reading of the words of the judgment at [66] which is submitted not to sit squarely with the Commissioners' conclusion at [98]. Analysing the judgment in this manner without regard to the expert evidence is misleading as to the evidence which was adduced before the Commissioners. A reading of the judgment as a whole does not lead to a conclusion that the modelling undertaken was agreed by the flood experts as disclosing no relevant increase in flood levels because of the modelling accuracy limits identified at [66].
2. The flood modelling evidence summarised in the judgment at [59]-[70] does not give rise to an implied finding that because of a range of accuracy of the flood models applied there was effectively nil impact identified in the flood modelling undertaken. For example, the Commissioners record at [64] that all three flood experts agreed that the modelling was reliable and provided accurate estimates of the impact of the proposed development on flood levels and velocities under local flooding conditions. At [70] the Commissioners stated that in relation to regional flood levels all three experts agreed there would be an increase as a result of the proposed development with various levels identified.
3. Summary of evidence in a judgment is necessarily shorter than the full extent of evidence provided at a hearing and the Commissioners' judgment should be considered in light of that evidence as a whole. As the Council's review of the evidence made clear the application of "logic" on this occasion does not accurately reflect the nature of that evidence. Tuite, a case in which a commissioner made a finding of fact in the absence of evidence capable of justifying that finding, has no application in this ground of appeal.
4. The Council also criticised the Commissioners' statement in the last sentence of [66] as incorrect submitting that the range of accuracy was not agreed by the experts and it was a statement in Mr Thomas' evidence only and not accepted by the other two experts. Regardless of whether this was inaccurate or not, it is clear from the expert evidence referred to in par 6 of the Council's written submissions that there was no agreement by the experts at the hearing that the modelled flood level increases by all the experts of any of the options were effectively reduced to no increase at all for those increases up to 10 mm.
5. This ground of appeal fails.

Ground 4 - denial of procedural fairness

1. The Commissioners' finding at [99] denied the Appellant procedural fairness. The hearing rule requires that the decision-maker alert the person entitled to be heard to the questions or "critical issues" to be addressed: Kioa v West [1985] HCA 81; (1985) 159 CLR 550 at 587 per Mason J; Ju Sheng Xia v Minister for Immigration, Local Government and Ethnic Affairs (1993) 27 ALD 668 at 673-674; Commissioner for the Australian Capital Territory Revenue v Alphaone Pty Ltd [1994] FCA 1074; (1994) 49 FCR 576 at 590-591.
2. In the present case the Commissioners appear to have fortified their decision in respect of the modelled scenario other than the 100/20 combination by pointing out a failure to model the refined fill footprint that could have confirmed the agreement of the expert witnesses that it would reduce the flood level on that scenario (see judgment at [99]), not the reverse of it as is implicit in the last sentence of [99]. To the extent that that is the case, the Appellant has been impermissibly deprived of the opportunity to provide evidence on that question.

Finding on ground 4

1. The authorities relied on by the Appellant for this ground need to be viewed in the context that these are adversarial merit review proceedings in which a proponent of development must satisfy the Court of the matters it considers are necessary to justify the granting of development consent. As identified in Forgall Pty Ltd v Greater Taree City Council [2015] NSWLEC 61 at [78], [86]-[87], where evidence is required to establish a particular factual matter in a merit appeal the responsibility to do so falls to a party which seeks to rely on that fact. There is no obligation on a commissioner to identify and provide an opportunity to a party to fill a gap identified in evidence where a party adopts a particular course leading up to and during a hearing in relation to the expert evidence it chooses to call.
2. The Appellant referred to the "amber light" approach in the court below (recorded at [84]) and in this appeal to support the submission that it was incumbent on the Commissioners to provide an opportunity to the Appellant to undertake further modelling (TS 27/05/15, p 64.49-65.08). The amber light approach was described in Maxnox Pty Ltd v Hurstville City Council [2006] NSWLEC 146; (2006) 145 LGERA 373 where Biscoe J highlighted the flexibility of Class 1 merit review proceedings under the Court Act and the objects of the EPA Act to conclude that the Court has power to give an applicant the opportunity to amend its application before the Court pronounces its final judgment: at [57]. A commissioner not giving an "amber light" to a development application before him or her does not give rise to a question of law. Whether such an approach is adopted is a matter of merit which must be weighed up by a commissioner in the exercise of his or her function as a consent authority under the Court Act.
3. The content of procedural fairness depends on the circumstances of the case (Alphaone at 713). In decisions cited by the Appellant above at par 35 the administrative decision-makers in various tribunals relied on material not provided by or to the affected party. Such authorities are not relevant to this ground of appeal in that the facts of this case are not the same. This ground is an impermissible attempt to raise a matter of merit in the guise of a failure to afford procedural fairness to the Appellant.
4. I also agree with and adopt the Council's submissions on this ground which referred to evidence from the flood experts at the hearing. The experts addressed flood modelling of various scenarios in their reports as identified at [59] and were questioned about the flood modelling. Mr Thomas' primary reason for not modelling 100 year ARI (Eastern Creek) and 20 year ARI (Hawkesbury River) local flood combination for modified option 2 (after having modelled it for option 1) was his view stated in the Joint Expert Report that the likelihood of the combination of those two events was "rarer than 1 in 100", at par 27(c). His second reason was the agreement between himself and Mr Bewsher (at par 28) that with a "small refinement" to the finished levels at the south-east corner of the site the flow path could be improved such that in the unlikely event of that 100/20 confluence there would probably be "acceptable" local flooding consequences. That is, water would not back-up behind the fill at that point and increase flood levels in the immediate vicinity offsite. Mr Bewsher also stated this in his statement of evidence, at par 41. This is not a case of the Commissioners making a finding based on the absence of a particular modelling scenario to the surprise of the Appellant.
5. Further, the Appellant's primary position before the Commissioners at first instance was that there was no need to model this combination because of the contention that it was "not identified in the DCP" as being a necessary modelling combination (TS 10/12/14, p 104.37-42). The positive submission was made that by cl 4 to the "Strategy Formulation Requirements" in Appendix C to the DCP the modelling was not required. It was open to the Commissioners in the exercise of their merit review function in the Class 1 appeal not to adopt that approach.
6. This ground of appeal fails.

Issue 2 - cl 20(2)(d) (failure to model stage 1 earthworks)

1. The two grounds addressing cl 20(2)(d) as set out in the amended summons are: 3. Insofar as it may have formed part of the Court's reasons for refusal, in making the finding at [103] that there was no modelling of the stage 1 earthworks, the Court : (a) failed to afford the Applicant procedural fairness because the fact that there was no modelling of the stage 1 earthworks was not a contention between the parties and the Court gave no notice to the Applicant that it proposed to rely upon it; (b) failed to have regard to the uncontradicted evidence that there was no need to carry out such modelling because of the modelling of the whole of the future proposed earthworks which included the stage 1 earthworks.

Ground 3(a) - procedural fairness regarding the absence of modelling

1. The Commissioners resolved at [103] that as no modelling had been undertaken of the proposed stage 1 earthworks they could not be satisfied there would not be any adverse flood impacts on adjoining properties. The Appellant submitted that they asked the proper question required by cl 20(2)(d) but on an improper basis. The absence of such modelling had not been an issue between the parties and no notice was given to the Appellant that that matter would be relied upon by the Commissioners in making their decision.
2. Although the Commissioners record submissions having been made by the Council's counsel regarding the absence of modelling of the cut and fill stage, and that no investigation of the impact of the earthworks had been undertaken (see judgment at [86] and [88]), this issue had not received attention in the proceedings prior to the hearing. It was not, for example, mentioned in the Council's contentions. It was not raised by the Council's expert as set out in ground 3(b) below.
3. Nevertheless, the Commissioners appear to have fixed on this absence of modelling of the earthworks as an exclusive basis for their refusal of the DA under cl 20(2)(d) (see judgment at [103]). Therefore, on the principles outlined in respect of ground 4 above, the Appellant was denied procedural fairness by being deprived of the opportunity to address that issue by obtaining the relevant modelling evidence.

Council's submissions

1. The failure to model the stage 1 earthworks was referred to at the hearing on several occasions, reflected in the finding at [103], that the Appellant's stage 1 construction (and cut and fill) plans considered part only of the cut and fill works on the site, and there were no final cut and fill and staging plans showing the proposed final modified option 2 configuration. Consequently there was nothing modelled for cl 20(2)(d) purposes to enable the Commissioners to be satisfied that no adverse flood impacts would occur to adjoining land at any point including during the construction phase.
2. Irrespective of whether that matter was raised directly in the contentions, it was raised without objection in the opening and during cross-examination. The Appellant joined issue on the matter and adduced evidence directly concerning it. The Appellant's narrow or technical pleading point should be rejected: see Leotta v Public Transport Commission (NSW) (1976) 50 ALJR 666 at 668; Water Board v Moustakas [1988] HCA 12; (1988) 180 CLR 491 at 497.

Finding on ground 3(a)

1. The context for these grounds is the consideration of cl 20(2)(d) of the SEPP that development cannot be approved unless it is not likely to result in adverse flood impacts on adjoining properties, including during the construction period of the development.
2. Having been taken by the Council's counsel to the transcript of the hearing before the Commissioners and the evidence relevant to the Council's submissions above, the lack of cut and fill plans for stage 1 of modified option 2 was identified from the outset of the hearing as an issue by the Council. It was the subject of cross-examination of expert witnesses. Appendix E to the FMS "Staging and Cut and Fill plans" was prepared before modified option 2 was contemplated. That was the option ultimately relied on by the Appellant in the course of the hearing before the Commissioners. The factual basis which underpins this ground of appeal alleging procedural unfairness is not established. The Council's reliance on Moustakas at 497 (citing Leotta) is apposite. My comments above at par 37 in the context of Forgall also apply to this ground. This ground of appeal fails.

Ground 3(b) - failure to have regard to uncontradicted evidence

1. The Appellant submitted that the uncontradicted evidence before the Commissioners disclosed modelling of the whole of the future proposed earthworks, which necessarily included stage 1. The FMS prepared by Mr Thomas was in evidence before the Commissioners. Appendix E to the FMS included the required "Staging and Cut and Fill Plans". The FMS states at par 35 and 36 that the cut and fill plan, which is "broadly based on Development Option 2", results in "a net cut and fill balance below 17.3 mAHD of 2.65 million m³". That figure was accepted by the Council's expert (see judgment at [55]-[56] and [108]) and represented "the total impact of the net loss of flood storage within the precinct from all DAs" (see judgment at [55]).
2. Mr Thomas also prepared the Appellant's FIA. In relation to the cl 20(2)(d) issue, the FIA concluded in table C1 of Appendix C: The development is proposed to be constructed in four (4) intermediate stages of development. Each of these stages will not have the potential to generate impacts greater than those determined and documented within this FIA Report. That is, each stage in isolation and/or combined will remain in compliance with the DCP (2009).
3. The Council's expert witness, Mr Bewsher, did not contradict that evidence in his responsive Floodplain Development Assessment. Therefore, there was no basis on the evidentiary record to refuse the DA based on the absence of evidence addressing subclause (d). The Commissioners holding to the contrary was erroneous.

Finding on ground 3(b)

1. It is debateable whether this ground identifies a question of law. The Council argued that this ground identifies a question of fact not a question of law. I agree in that the issue really complained of is that Mr Thomas' opinion was not accepted by the Commissioners. Alleging "no need' to have regard to evidence is a merit argument. The ground also does not properly reflect the findings of the Commissioners when the judgment is read as a whole.
2. Further the evidence of Mr Thomas in the FMS at par 35 and 36 which the Appellant relies on was contradicted in any event. That submission is supported by the Council's references to what occurred at the hearing.
3. The Appendix E site-wide cut and fill plan to the FMS dated 19 September 2014 was identical to the site-wide cut and fill plan that was Appendix D to the FIA dated 19 September 2014 which was prepared only for the option 1 proposal (TS 10/12/14, p 90.25-50).
4. Mr Grech, town planner called by the Appellant, accepted in his oral evidence that there were no final earthwork and cut and fill plans that would reveal where fill was to be placed, and what final levels would be. Cut and fill plans for the various stages of works (save for the stage 1 section) were not provided. Mr Grech accepted that that detail would follow "with future development applications" (TS 10/12/14, p 98.08). The Commissioners found that without this cut and fill plan they could not be satisfied that there would be "no adverse flood impacts", noting that cl 20(2)(d) also requires satisfaction during the construction phase of work. If there were no final cut and fill plans, or staging plans beyond the Stage 1 plans, there was necessarily a need for further modelling and assessment.
5. No error in the Commissioners' reasoning in [103] whether factual or legal is established. This ground of appeal fails.

Issue 3 - regional impacts

1. Ground 2 as set out in the amended summons states: 2. In rejecting the application on the basis of regional impact at [105] the Court erred in law in that: (a) the Court applied the wrong test by applying the test under cl 20(2)(b) of the SEPP which does not apply to regional impact; (a1) In the alternative to (a) above, in finding that, for the purposes of the DCP, the carrying of out of the proposed development would result in an increase in flood levels on a regional level the Court erred in law as, on the evidence before the Court, properly considered, there was no evidence to support the finding, or alternatively the facts before the Court were incapable of justifying that finding either directly or by inference. (b) the Court failed to take into account the Riverstone West Development Control Plan 2009 ("the DCP") and in particular clause 4.2 and Figure C2 of Appendix C and the evidence in relation thereto; [amended at hearing to the whole DCP does not refer to regional impacts therefore no requirement to consider] (c) the Court failed to afford procedural fairness to the Applicant because objective (2) was not a contention between the parties and the Court gave no notice to the Applicant that it proposed to rely upon it; (d) insofar as the Court was permitted to consider objective (2) in doing so it failed to take into account the DCP, and in particular clause 4.2 [judgment [44]] and Figure C2 of Appendix C [judgment [45]] and the evidence in relation thereto.
2. The Commissioners made findings on regional impacts at [104]-[105]. These five grounds of appeal are somewhat difficult to understand in the context of the judgment. All purportedly arise from the third and fourth sentences in [105] which immediately suggests an overly critical approach to the judgment as the Council submitted. Given the clear determination under s 79C(1)(e) of the EPA Act in the first two sentences of [105] that there were unacceptable regional flood impacts any errors in the third and further sentences cannot be vitiating in any event. Grounds 2(a), (b) and (d) should be considered together. Grounds (b) and (d) in particular appear to overlap to a large extent. Ground 2(a1) can be considered discretely and I will consider that ground first. Ground 2(c) can also be considered separately.

Ground 2(a1) - Commissioners' finding regarding regional impact (alternative to 2(a))

1. The Appellant submitted that the Commissioners erred in law in finding a regional flood level increase based on the evidence. At [105] the Commissioners refer to an agreement between the expert witnesses "that there will be an increase in flood levels at a more regional level". The relevant levels of increase are identified as "for option 1 … no more than 12mm; for modified option 2, … the range is 5mm to 9mm" (see judgment at [70]). The experts "agreed that the accuracies of flood models are traditionally considered to be 10 to 20 mm (see judgment at [66]). In other words, at regional level increases of between 5 mm and 12 mm, the expert witnesses effectively agreed that the model was not sensitive enough to predict one way or another that there would in fact be an increase for one of the options (modified option 2), and also for the main part of option 1 (up to 12 mm).
2. Alternatively, in accordance with the Appellant's submission on ground 1, the test for cl 20(2)(b) of the SEPP should be interpreted to allow for trivial and negligible departures from the relevant standard.

Finding on ground 2(a1)

1. Ground 2(a1) identifies an issue of fact not a question of law. For the reasons already identified in relation to ground 1A (effectively the same issue) above at par 30-34, the experts' findings of likely increases in regional flooding are not to be regarded as reduced to nil by the words used by the Commissioners to describe the modelling sensitivity at [66]. Read in the context of the judgment as a whole, this submission must be supported by expert evidence not a submission from the bar table that there should be an assumption of nil impact.
2. In the alternative, I have not accepted the submission that no increase should be read as allowing trivial or negligible increases above in ground 1 at par 19-26. The same finding should apply to this ground. This ground fails.

Ground 2(a) misapplication of cl 20(2)(b) of SEPP to regional impacts

1. The Appellant submitted that, first, the Commissioners applied a very strict interpretation of cl 20(2)(b) of the SEPP to an issue under the DCP (see judgment at [105]). There was simply no warrant for "applying the same logic" in this way, and the Commissioners proceeded on that basis without even seeking to explain why it was importing a test from one instrument into another.
2. The DCP does not require that a DA be assessed in respect of regional flood impacts, or a statement of the test that should be applied to such an assessment. Equally, there was no indication in the SEPP that the subclause (b) test applies beyond flooding on "adjoining properties".
3. The Commissioners' direct application of a test from the SEPP to an issue said to arise under the DCP was a curious outcome given its express acknowledgement of these points, and the distinction between the two documents at [105].
4. While the DCP's focus was said to be to "regional impacts", the subclause of cl 20(2) of the SEPP from which the Commissioners imported the test it applied related to "flood levels" (subclause (b)). There is also present in cl 20(2)(d) a test applicable to "flood impacts". Even if it were appropriate for the Commissioners to look to cl 20(2) of the SEPP for guidance on assessing the DA in respect of regional impacts, it is submitted that the (qualified and qualitative) test of the likelihood of "adverse flood impacts" should have been the touchstone, rather than the (as construed by the Commissioners, unqualified and merely quantitative) test of whether a proposed development would "increase flood levels". The Commissioners clearly applied the wrong test in respect of the regional impacts issue.

Ground 2(b) - the whole DCP does not refer to regional impacts therefore no requirement to consider regional impacts

1. The Appellant submitted that the Commissioners' interpretation of the DCP so as to impose an additional requirement in respect of regional flood impacts was inconsistent with that instrument read as a whole, and in particular s 4.2 and Figure C2 of Appendix C.
2. Section 1.4.1 of the DCP states that the DCP is intended "to provide additional objectives, controls and guidance to applicants proposing to undertake development in the Riverstone West Precinct, and for Council reference when assessing DAs", but "should be read in conjunction with" the SEPP "which provides the statutory planning controls for development in the Precinct". It emphasises that the DCP "is consistent with and supports [controls under the SEPP] by providing more detail in relation to how development is to occur in the Precinct". That language would militate against the imposition of a regional impacts criterion for flooding that was not clearly stated in either the SEPP or the DCP, and is in addition to the requirements of cl 20 of the SEPP on flooding issues.

Ground 2(d) - failure to consider development objective (2) in context

1. The Appellant says that the Commissioners' interpretation of development objective (2) of s 2.2 of the DCP so as to support an additional requirement in respect of regional flood impacts was inconsistent with the DCP as a whole, and in particular s 4.2 and Figure C2 of Appendix C. In that respect, the Appellant repeats its submission under ground 2(b).
2. Furthermore, to the extent that the Commissioners considered that the stated goal of ensuring that "development does not cause any offsite flood impacts that are unacceptable to Council" reinforced an interpretation of the DCP that required proposed development not to have any flood impacts at a regional level (as opposed to merely "offsite"), it is submitted that the Commissioners overstated the effect of development objective (2).

Council's submissions

1. The findings section in the judgment commences at [91] and should be considered as a whole. The regional impacts are considered under s 79C of the EPA Act not only cl 20(2)(b) of the SEPP and the DCP. Any error identified by these grounds cannot be vitiating.

Finding on grounds 2 (a), (b), (d)

1. As the Council submitted the judgment must be considered as a whole in relation to regional flooding impacts and that informs the findings at [105] which are impugned in these grounds of appeal. The issue of possible regional flooding impacts was identified as an issue of concern by the Council (see judgment at [90]). It was addressed extensively by the experts. Most of the summary of the experts' evidence from [58]-[74] refers to the results of various flood models dealing with regional impacts of flooding as well as local. The Commissioners' judgment at [70] records that all three experts agreed that there would an increase in regional flood levels as a consequence of the proposed development, the increase for the modified option 2 being in the range of 5 mm to 9 mm. Their different views on the likely costs as a result of increased flooding is identified at [72]. At [73] Mr Thomas and Mr Bewsher are quoted as agreeing that cumulative impacts of fill across the floodplain must be considered. They disagreed on whether this had been assessed correctly in the FMS with Mr Bewsher considering that cumulative impacts had not been assessed correctly, were not negligible and the consequences of even small rises in the regional flood levels are considerable and should not be ignored. The Commissioners' findings on the evidence are identified in [104]. The Commissioners identify the need for modelling beyond the immediate local impacts in order to comply with the NSW Floodplain Development Manual 2005. They agreed that the approach in the FMS of an impact area of about 98 km2 described as "local" was appropriate. That is the scale of modelling the Commissioners are addressing at [105]. As the Council submitted, an important part of the Commissioners' reasoning at [105] in relation to unacceptable offsite impacts is that these would include significant social and economic effects given the expert evidence of potential additional cost for each millimetre increase in flooding at [71]-[72].
2. Regional flooding impacts were squarely raised as an issue in the proceedings by the Council, addressed by the experts and whether the SEPP or the DCP explicitly required its consideration does not mean the issue goes away. The expert evidence clearly identified that it was relevant in the context of the FMS, as described at [104]. As the Council submitted and the judgment demonstrates, the Commissioners considered regional impacts beyond cl 20(2)(b) of the SEPP and the DCP as a necessary consideration under s 79C(1)(e) of the EPA Act. The conclusion in the last sentence of [105] that the regional flooding impacts are not "acceptable" is not a reference solely to the s 2.2(2) development objective in the DCP. It also refers back to the second sentence in that paragraph "the public interest under s 79C(1)(e)". Section 79C required that matter to be considered as part of the public interest. I agree with the Council that properly read the Commissioners' findings addressed whether the modelled flood impacts would be unacceptable as a matter of merit and in the public interest.
3. When the judgment is read in a balanced way the relevant sentences of [105] the subject of this ground of appeal demonstrate that the Commissioners were attempting to apply the available instruments, namely the DCP and the SEPP, in a coherent manner to the regional/local impacts arising from the modelling described in [104], which application did not necessarily arise in a coherent way from the instruments themselves. I have not referred to later parts of the judgment where the Commissioners discuss the shortcomings of the DCP in particular in its application to the subject land.
4. Further or alternatively, consideration of regional impacts was relevant under the DCP as the Council submitted. At [104] the Commissioners noted that the DCP at Appendix C required an applicant to formulate an FMS. The Appellant sought approval for the FMS as the basis for the modified option 2 works. The Commissioners observed at [104] that in preparing that FMS the Appellant had to do so by reference to the SEPP, and also the NSW Floodplain Development Manual 2005 which has a broader focus. Consequently, the criticism in ground of appeal 2(b) of the application of the DCP to regional flood impacts cannot be sustained when the instrument as a whole is considered. The Appellant referred to parts of the DCP in written submissions in 2(b) at par 90-96 such as the objective in s 4.2 referring to management of flooding impacts in accordance with the SEPP, earthworks to be controlled by reference to documents that apply across the subject land being the FMS, the staging plan outlining the staging of all earthworks for the precinct and Figure C2 of Appendix C, which depicts the preliminary cut and fill plan for the precinct. The Appellant relied on the fact that none of these parts of the DCP referred to regional impacts expressly. The Appellant submitted that there was no reason to apply that instrument in a regional context. In ground 2(d) the Appellant argued the Commissioners' interpretation of development objective (2) incorrectly supported its application in a regional context. I cannot agree for the reasons identified immediately above.
5. Ground 2(a) criticises the application of cl 20(2)(b) of the SEPP in a regional context. Firstly there was no warrant for doing so because the term "regional" does not appear in cl 20(2) of the SEPP. The Commissioners' statement in the first sentence of [104] that the focus of cl 20(2) is adjoining land meaning local informs the meaning of the third sentence of [105] when they refer to cl 20(2)(b) of the SEPP. The Council submitted as a statutory construction argument that the Commissioners were referring to the undefined phrase "adjoining properties" in cl 20(2)(b) as applying not just to land physically abutting the large Lot 211 but to land more remote from the site. It does not appear that the Commissioners were approaching the matter as one of statutory construction of the SEPP. Rather the Commissioners were, as a matter of logic, applying the same approach in the SEPP to local flooding to regional flooding, at least to the extent of the modelling identified in [104]. That is really a matter of merit consideration grounded in the public interest by the Commissioners rather than a failure to properly apply the SEPP. Whatever was intended by the Commissioners there is no vitiating legal error.
6. Secondly, the Appellant argued that if the SEPP could be applied, subclause (d) of cl 20(2) should have been applied by the Commissioners rather than subclause (b). Clause 20(2) states that approval cannot be given unless a consent authority is satisfied of all four matters referred to in subclause (a)-(d). If the SEPP can be applied in this context no error in application of the SEPP arises applying subclause (b) rather than (d) given that statutory context.
7. These grounds of appeal fail.

Ground 2(c) - procedural fairness regarding development objective (2) in s 2.2 of the DCP

1. The Appellant submitted that following the finding that the proposed development should be refused because of its regional impacts, the Commissioners "note[d] Development Objective (2)" in the DCP, which is to "ensure development does not cause offsite flood impacts that are unacceptable to Council", and stated that, "[o]n the evidence before us we cannot be satisfied that the offsite flood impacts would be acceptable", at [105]. Although the Commissioners recited the terms of development objective (2) in the course of their reasons (see judgment at [32]), no submissions in respect of its application to the DA were recorded. Nor was there any discussion by the Commissioners as to whether this development objective imposed a planning control against which the DA should be assessed.
2. The application of development objective (2) was not an issue between the parties in the proceedings below. It was not addressed in the Council's contentions, and it was mentioned on only two occasions, both times in passing, during the hearing (see TS 09/12/14, p 8.3-5 and TS 10/12/14, p 105.23-30). To the extent that the Commissioners relied upon development objective (2) as a separate basis for refusal of the DA, or a reason for confirming their decision on the application of the test in cl 20(2)(b) of the SEPP to the regional impacts issue, the Commissioners did so without giving notice of an intention to rely on that matter adversely to the Appellant.

Finding on ground 2(c)

1. The Council's submissions demonstrate that this issue was identified below in opening submissions by the Council and was addressed throughout the hearing given the expert evidence about off-site impacts. The issue was also raised by the Appellant (TS 10/12/14, p 105.23-30). I also consider this criticism of the Commissioners' findings is with an eye to error given that whether off-site impacts are acceptable is clearly a relevant merit matter regardless of whether words so stating appeared in the DCP or not.
2. This ground of appeal fails. The Appellant's appeal is dismissed.

Orders

1. The Court makes the following orders: 1. The Amended Summons Commencing an Appeal dated 16 April 2015 is dismissed. 2. Riverstone Parade Pty Limited is to pay Blacktown City Council's costs unless a motion setting aside that order is filed on or before 4 September 2015.

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