4 The on-site hearing was attended by:
* Mr A. Caughey junior, Mr A. Caughey senior, who represented Cranebrook Sales
* Mr M. Freeburn, surveyor;
* Mr V. Hardy, townplanner;
* Mr G. Ryan, engineer.
Attending for the Council was:
* Ms K. Poulos, barrister;
* Mr A. Wood, engineer;
* Mr M. Bullivant, solicitor, and
* Mr P. Warwick, surveyor, and
* Mr W. Stimson, townplanner.
5 The proposal in Exhibit A is to create the subdivision with a battle-axe lot at the rear of approximately 1473 sq m leaving a street front allotment of 550 sq m. The street front lot would have a frontage of just over 16 metres leaving a driveway for the rear lot of 4 m. A site for a new house is proposed 5 m downhill from the common boundary between the street front lot and the rear lot, and the envelope is shown as 15 m wide and 8 m deep. It is located between contour 44.9 and contour 45.5.
Issues
6 The issues in the appeal are in summary:
1. that the new battle-axe lot is largely flood prone in the 1 in 100 year flood zone and the Council has a policy not allowing subdivisions that create lots within that flood plain.
2. Also the house envelope is located in a position where it would require filling to bring the house above flood level and this is not favoured for various reasons.
3. The Council considers that the whole of the Wallacia village is a high hazard area due to the fact that in the 1 in 100 year event the town would be completely isolated and would require evacuation. Therefore Council officers do not favour increased further development of the village via subdivision of flood fringe land.
7 The applicable statutes and controls are:
the Penrith Local Environmental Plan 2002 for the villages of Mulgoa and Wallacia; the Penrith Development Control Plan 2006 relating to flood liable land; the ' Flood Plain Development Manual' [NSW April 2005].
The Evidence
8 At the on-site hearing we looked at the subject property and noticed that on its northern side is the Wallacia Public School with several of its buildings lower down the hill and therefore within the flood plain. Obviously the caravan park below the site is well within the flood plain. On the southern side of the subject property are two lots of similar size to the subject site having similar houses up near Mulgoa Road. The lots also back onto the caravan park. Further south from these houses and lower downhill are two storey or one storey houses above garages, along the street that serves the caravan park. They are in the flood plain. In other parts of Wallacia there are existing houses below the 1 in 100 year flood plain, however these have been limited so some extent by the zoning of the village, which contains them to the Zone 1 (VR) Residential area. Beyond that zone are rural zones.
9 The site is wholly within Zone 1(VR) and its objectives are:
(a) to provide for the housing needs of Penrith rural villages, and
(b) to protect the rural character of these villages; and
(c) to ensure that the nature and scale of these new developments is compatible with the existing development.
10 Permissible with consent in that zone are bed and breakfast establishments, dwelling houses and ancillary structures, cafes or tea-rooms, child-care centres, community facilities, dual occupancy development, educational establishments, guest houses, health care consulting rooms, home businesses, places of assembly, places of worship, recreation areas, recreation facilities, tourist establishments, and utility installations of various kinds.
11 The surveyors were both in agreement that the 1 in 100 year flood level on the subject site would reach RL 45.8 m and the proposed dwelling being located between RL 44.9 and 45.5 would require some filling to enable the house to be built with half a metre freeboard above the maximum floor height, or be erected on piers. The battle-axe driveway would also require some filling if it is to be kept free of flood water in that 1 in 100 year event.
12 However, it was pointed out to me that in the Council's Development Control Plan 2006, the Safe Flood Access criteria is driveways having a depth of flooding up to a quarter of a metre depth with low velocities. In the case of the subject property even if the driveway was not filled in its last few metres, it would only be 0.55 m deep in water at its end at the house envelope. Therefore it would only need 300 mm of fill to raise it to an acceptable level that would allow easy and safe evacuation to the higher land in Mulgoa Road; ie. the village on the hillock.
13 Mr Wood had produced a Council map of Wallacia which identified the 1 in 100 year flood line for most of the village including the subject site. At a rough estimate it showed that in the 1 in 100 year flood the property would be about two thirds underwater. The water would be at zero depth at the uphill boundary of proposed Lot 92 and about 900 mm at the north-west corner of the dwelling envelope. A greater depth at the rear boundary would be about four metres. However, this is at a distance of about 55 m from the house.
14 In Mr Ryan's opinion, the proposal to have the subdivision and locate the dwelling in the position shown by the building envelope (it would be bound by a s.88B instrument on title), would pose no serious risk to the safety of the occupants of the proposed dwelling. And minor filling on the edge of the flood plain would not redirect flood waters or adversely affect flood behaviour in the 1 in 100 year event.
15 He agreed with Council engineer, Mr Wood, that the topography around Wallacia is fairly unique and that the probable maximum flood (PMF) had been calculated at being up to 9m higher than the 1 in 100 year event. This is apparently related to the narrow space between Wallacia and the Blue Mountains and the volume of water which would run off the catchment in the huge storm needed to create the maximum flood.
16 Where Mr Wood and Mr Ryan part company is in the identification of the risk factor of the site.
17 Mr Ryan and Mr Hardy said that because of the distance of the site from the river being about 200 m and the shallow depth of water on the site, particularly on the location of the proposed house-site, that the flow velocities on this flood fringe area would be very small and would not have any destructive impact.
18 He said that the classification of flood hazard are three main categories:
1. floodway
2. flood storage
3. flood fringe.
He said the site would be classified as "flood fringe" and minor filling proposed would result in negligible change to the flood level or flow characteristics due to the size of the flood plain and the distance from the river.
19 Under the NSW Flood Plain Development Manual, he believed the site would be classified as low hazard - "flood fringe," and this would fit with the requirements of the Council's DCP 2006:
"That any development will not increase flood hazard or risk to any other properties; nor will it be affected in its structural adequacy of any building and that building be sited in the best position to avoid flood waters and allow easy access for evacuation".
20 Mr Wood agreed with Mr Ryan up to a point, however he took a broader view of the definition of high hazard area as applied under the statute and controls. He said because of Wallacia becoming isolated in the 1 in 100 year event , he considered that the whole village is high hazard even though there are areas that may be above the 1 in 100 year flood.
21 His opinion is principally due to the isolation of the village and creates a potential demand on State Emergency Services for evacuation of houses below the flood plain, and the need to sustain food and shelter to those above the flood plain, with the potential need for evacuation. He said part of this opinion is based on the State Emergency Services estimate that in a major storm there may only be one hour's warning of major flood waters coming down the river. This would cause an emergency situation, and the SES currently estimates that if it did need to evacuate the village, it would need three hours to do so.
22 From the evidence I formed the opinion that this is the crux of the difference between the parties. The subdivision complies with all the Council's requirements in other regards in consideration of the flooding issue.
23 Site filling could actually be avoided by constructing a new dwelling on short piers to the required height above the flood plain including the short length of driveway that might be required to be elevated. Mr Stimson said it would be possible to build a two-storey house on the building envelope provided at the north-west corner it was not two-storeys, so that the Council's maximum building height could be complied with.
24 In turning to the question of flooding and how it might prohibit or permit a subdivision I was taken to the wording of the applicable instruments and controls.
25 An overall opinion on the matter came from the applicants submissions and evidence being that:
"if the Council considers the whole of Wallacia a high hazard area, and therefore this subdivision should not be permitted, then the Council should be refusing subdivisions of any land above the flood height. Also it should refuse any dual occupancy application which might intensify or increase the population of Wallacia if the time of evacuation or difficulty of sustaining the village if isolated by flooding are the determining factors".
26 The applicants submitted and it was not contested by the Respondent, that subdivisions had been granted in the very recent past for other lots in Wallacia. Admittedly they are entirely above the flood plain, however, if the Council's policy is as indicated it would mean that additional new dwellings proposed in Wallacia should be prevented.
27 The applicant also noted that the whole of its allotment is zoned for village residential purposes and has been zoned that way for many years. Further, that the zoning has actually been renewed at the time of the Council gazetting its Local Environmental Plan 2002 (LEP). If the Council was concerned about the whole of Wallacia being "high hazard" then land below the 1 in 100 year flood line should not be the current zoning.
Turning to the Local Environmental Plan in summary :
Cl 17(1) cites the objectives of controlling developments on flood prone land; and
Cl 17(2) says that consent must not be granted to development on or adjacent to flood liable land unless the provisions of any Council policy for the development of flood liable land have been taken into consideration by the consent authority;
Cl 17(3) says further, that consent must not be granted to developments on land inundated as a result of the 1 in 100 year flood event, which in the consent authority's opinion will significantly adversely affect potential flood behaviour including a flood peak at any point upstream or downstream or on adjoining lands or that would increase a potential flood hazard or flood damage to property, or would affect safety of proposed development in time of flood, or restrict the capacity of the floodway or increase the need for Council or State Emergency Services personnel, welfare facilities or other resources associated with an evacuation resulting from flooding. Further that any development in the flood plain should not increase the risk to life and personal safety of emergency services and rescue personnel.
28 The two engineers were in agreement that the resulting battle-axe lot of the proposal is subject almost entirely to flooding in the 1 in 100 year event, even though it is fringe flood area.
29 It is significant in the wording of cl 17(3) that each of the aspects of concern are alternative, not conjunctive. Bearing these alternatives in mind the respondents evidence is based on cumulative effect if an approval of this subdivision creates a precedent for other lots to subdivide. The respondent conceded that this individual lot would not cause any potential change of flood behaviour upstream or downstream or on adjoining lands, or increase flood hazard or damage to property, although it is concerned about safety as I described earlier in regard to evacuation of the whole of Wallacia.
30 The Council estimates that there are twenty-nine lots in Wallacia that may potentially seek subdivision if this allotment is approved. The applicant said there is only this lot and the other two similar lots adjoining and adjacent that would be able to seek subdivision. All of the other land was either deeper in the 1 in 100 year flood area, or part of the river reserve, or held by government authority, or too small except for dual occupancy.
31 The respondent submitted that within the whole of the Penrith local government area there could be up to 500 other lots that could be seeking subdivision if this development was approved, and that the cumulative effect of those, may in fact have some effect on flood behaviour along the flood plain.
32 The applicant said that this submission had no evidence that they could address and should be disregarded. at this hearing.
Conclusions
33 After considering this evidence I have formed the opinion that none of the statutory provisions of cl. 17(3) of the LEP would constitute sufficient reason to refuse the proposal, on any basis put by the respondent. It seems to me that the location of the dwelling on the proposed new lot is in such a location that it could not constitute grounds that would increase the need for the Council, or State Emergency Service or personnel or welfare facilities or other resources associated with evacuation to be increased to an extent that would justify a refusal. Nor would it pose an increased threat to life and personal safety of emergency services personnel. Even with the one hour warning that Mr Woods said could occur in a 1 in 100 year flood, any occupants of a future dwelling on the battle-axe block would only have to walk out the back door and uphill a few metres to be safe. Indeed, it occurred to me that even that would not be necessary since the dwelling is on the very edge of the flood plain, and if properly constructed as required by the statutes and controls it would be in no risk of either inundation or being washed away.
34 The probably maximum flood (PMF) although much higher than the "standard flood" is not used for design or town planning purposes. The 1 in 100 year flood is the standard.
35 Obviously the statutes and controls envisage development within flood prone land provided certain tests are passed. The major test, once an application has passed those raised in the LEP, is contained in Development Control Plan 2006.
36 In Part 2 s.2.10 Flood Liable Land, Cl (1) in Part A states:
"the primary objective in NSW flood prone land policy recognises the following two important facts:
+ flood prone land is a valuable resource - it should not be sterilized by unnecessarily precluding its development
+ If development applications are assessed according to rigid and prescriptive criteria, some appropriate proposals may be unreasonably disallowed and restricted; and some equally quite inappropriate proposals may be approved".
37 The DCP goes on to say that flood mitigation works and removal of development in high hazard areas via voluntary acquisition is envisaged, together with the minimisation of other losses due to flooding through effective planning and development controls. Development within flood prone land should be dealt with on an assessment of merits, in terms of social, economic, ecological and flooding.