5 The applicant contends conditions 13 (c) and (d) are inappropriate on a subdivision permit, if necessary they should be on a development permit. In this respect the applicant notes in a previous Tribunal determination in relation to development on Lot A these conditions were rejected and there is no proposal for development on Lot B.
6 In relation to condition 13(f) the applicant contends this condition is invalid as it has no nexus with what has been permitted. It is submitted the subdivision of the land into 3 lots does not create any need for additional drainage nor does it prevent Melbourne Water taking steps to acquire part of the land if it considers this is necessary in the future to achieve an environmental design in accordance with its current policy for the design of new waterways.
7 Melbourne Water contends the conditions are necessary as there are no adequate controls to ensure future development on Lots A and B is appropriate so that there is no impact on flood levels and no impact on any future works in the waterway. In this respect it is submitted the 40m wide drainage easement to be contained in Lot B is required to enable appropriate drainage requirements to be put in place for properties along Potts Road which are all affected by the associated flood levels of the Potts Road Drain and to ensure the availability of access to the waterway. This drain is located at the rear of the land.
8 It is Melbourne Water's view that as Lot B is entirely subject to flooding any development in Lot B is inappropriate as it poses a danger to people and property, will increase the impact of flooding on upstream properties by reducing the storage capacity of the naturally occurring retarding basin that encompasses the lot and will also restrict the management of the floodway by potentially impeding or limiting the nature of works that can properly be undertaken by the flood plain manager to limit or mitigate the effects of flooding. As the waterway manager it is the only opportunity Melbourne Water has to obtain access over private land to properly perform its functions.
9 Melbourne Water also expressed the view that if there are no restrictions on development of Lot B at this subdivision stage there is no ability in the future to prevent inappropriate development as the existing legislative requirements do not require the Responsible Authority to refer development applications to Melbourne Water and there is at present no need for a permit for development for residential purposes on Lot B. There is no proposal for any development on Lot B and as a result of the quarrying activities on the land at the rear it is subject to set back requirements.
10 The subject land is located on the north eastern side of Potts Road, Langwarrin. The site is 'L' shaped and has an overall area of 8231m ² with a frontage width of 29.89m and a rear boundary width of 56.03m. It is subdivided under the permit into 3 lots. Lot 1 has an area of 753m² and contains an existing dwelling. Lot A comprises 6 separate parts with an overall area of 3262m² and is to contain 20 dwellings yet to be constructed. A permit was issued by the Tribunal for the development of the 20 dwellings[1]. Lot B has an area of 2243m² and is 56.03m wide and 40.03m deep.
11 An existing 8.05m wide drainage easement in favour of lots on LP 52070 runs across the site close to the rear (north eastern) boundary and is now contained in Lot B.
12 The subject site is one of several substantial lots on the north eastern side of Potts Road zoned Residential 1 that are yet to be fully developed. Opposite the site is existing residential development. The site is also subject to Development Plan Overlay Schedule 1.
13 To the north west and south east adjoining the site is a double storey brick dwelling and a single storey concrete dwelling and bungalow. To the rear is land used for extractive industry by Burdett's Quarries. This land is separated from the subject site by dense vegetation. This area of land to the north east is subject to Amendment C35 which has been exhibited. C35 in summary proposes to rezone the land to Residential 1and Rural Conservation, and apply a Development Plan Overlay that includes transfer of the remnant bushland to the Crown.
14 The land has a fall of approximately 5m to the north east mainly within the wider, rear portion of the site. Vegetation on the site is sparse except for an area of dense bush adjacent to the rear north eastern boundary contained in Lot B. It is this area of dense bush that Melbourne Water has indicated should be included within a drainage easement to be retained as a 'natural' open waterway. The rear of the subject site is traversed by the Potts Road Drain (waterway). In this section it is a small ephemeral stream. The channel is generally a shallow depression approximately 50 cm deep and 2m wide.
15 Whilst Lot B is said to be flood prone this land is not subject under the Frankston Planning Scheme to either an Urban Floodway zone or Land Subject to Inundation Overlay. Mr Daff indicated that in a 1 in 100 year storm event the flows are not contained in the Potts Road waterway which traverses the rear of the site hence the low land abutting the waterway which includes Lot B is flooded. The existing 8m wide easement which was created at the time of the creation of the lots in Potts Road is considered satisfactory for a low-density subdivision but it was never intended to carry the runoff resulting from a 1 in 100 year flood event on an urbanised catchment. Mr Daff also indicated the waterway was located outside the easement for some of its length.
16 Details of the catchment were summarised by Mr Jackson. The subject land is located within the catchment of the Potts Road Main Drain a declared main drain[2]. The Potts Road catchment has an area of 124ha at Valley Road. The catchment is made up of 63ha of residential land, 51ha of rural conservation land and 10ha of low density residential land.
17 The upper catchment is approximately 65ha, upstream of Cranbourne-Frankston Road; in this area the former watercourse has been undergrounded. At the end of Raneen Drive, the pipe system outfalls to an open watercourse[3]. The waterway flows in a northerly direction across a vacant block of land before entering the Burdett's Quarry property. The waterway meanders through the quarry before flowing into the properties that adjoin Potts Road. It meanders through these properties before re-entering the quarry north west of the Site. The waterway crosses under Potts Road just south of Valley Road, where it then flows in a westerly direction to Boggy Creek. The area immediately south of Valley Road and east of Potts Road is described as a natural basin in which flood waters pond, flowing out at a reduced rate.
18 According to a survey plan of a portion of the Potts Road Waterway a 'bottleneck' occurs along the Potts Road floodplain on the boundary between No 70 and 74 Potts Road. It is said that the 63m contour forms the bottleneck and restricts flow along the floodplain. Melbourne Water indicates that in the 1 in 100 year ARI event floodwater ponds upstream of the restriction to a level of 62.70 to push the flood water through the restriction. The flood level is horizontal upstream of the restriction, including that section across the subject property because of the increased waterway area due to the raised flood level.
19 Mr Daff indicated as a result of the construction of the diversion drainage pipeline along the Cranbourne-Frankston Road after the development of Cranton Rise when Potts Road properties experienced increased flooding, this has resulted in floodwater being stored in the floodplain at a level of 62.70 and protects the downstream properties from higher flood levels. Mr Daff also expressed the view that waterway enhancement works are likely to result in an opening up of the bottleneck.
20 Mr Daff expressed the view that any filling would result in higher flood levels both up stream and down stream. If there was full development of the catchment and no filling or enhancements to the waterway, the flood level across the subject site is 62.70, if the flood plain were filled leaving an 8m corridor the flood level would increase to 63.25.
21 The Potts Road West Drainage Scheme was established in 1990. The Scheme is designed to cater for the increased load on the drainage system that would result from urban development of the rural land north of the Cranbourne-Frankston Road. Mr Daff indicated that the waterway channel and floodplain will need to be reshaped to ensure that the development of this sub-catchment, including the development of the subject site, does not collectively impact upon existing flood levels on properties both upstream and downstream.
22 Proposed work in the waterway are expected to result in a 'natural waterway' 1m or less in depth to allow piped drainage from developments along the creek to connect to the waterway. An access track approximately 6m in width is said to be required along the creek to allow maintenance/construction machinery access. Land adjoining the track is to be planted with indigenous vegetation.
23 To be valid, a condition in a planning permit must fairly and reasonably relate to the permitted development or the condition must be reasonably capable of being regarded as relevant to the implementation of planning policy as ascertained from the PE Act and relevant planning scheme[4].
24 The condition in 271 William Street requiring a splay corner to allow pedestrians to cut across the corner did not relate to the construction or use of the building proposed on that site but it was found it did relate to the planing policy in relation to pedestrian movement applicable to the area in which the building was to be constructed. As summarised in Rosemeier it does not have to be relevant to the development in the sense of being necessary in the interest of the development itself[5]. But conversely that does not mean that just any planning purpose discernible is sufficient if the purpose or policy is in fact quite unrelated to the permission being granted[6].
25 Whether a condition was reasonably capable of being related to the implementation of planning policy in the relevant sense is a question of fact[7].
26 In terms of the Frankston Planning Scheme there is a general policy within the State Planning Policy Framework identifying that Responsible Authorities should assist in the protection and where possible restoration of catchments and waterways and to consider any relevant floodplain or catchment management strategy[8].
27 The policy at clause 12.07 seeks a reduction of the impact of stormwater on catchments and at clause 15.01-2 Responsible Authorities are encouraged to assist to protect and where possible restorate catchments and waterways. Responsible Authorities are encouraged to consider the impacts of catchment management on downstream water quality and where possible should encourage 'measures including the preservation of floodplain or other land for wetlands and retention basins, to filter sediment and wastes from stormwater prior to its discharge into waterways' and to