Mt Albert - Owairaka management plan

5.0 Natural and physical environment

5.1 Physical description

Mt Albert - Owairaka provides an area of open countryside that offers a rural and natural atmosphere and respite from the surrounding urban area. The value of such an area in the city is increasing as the current population grows and the city intensifies.

The main entrance to Mt Albert - Owairaka is from Summit Drive. On the right of the entrance is a disused water reservoir, while on the left is a second flat grassed area where a reservoir was once located. Also to the left is a small picnic site. A ring road climbs up the north-east side of the cone past the northern face of the mountain where grassland is interspersed with mature vegetation on the slopes below the ring road.

The ring road provides access to an archery range on the floor of the old quarry on the east side of the mountain. Access to the range is through the old quarry entrance and it contains a small unsealed carpark and an interpretative plaque. The former quarry is now a flat grassed area, semi circular in shape, with the walls being a mixture of grass and established mature trees. A small building is situated adjacent to the archery range. Below the ring road on the eastern side, the land falls away steeply. This slope is grassed and contains a few mainly native trees.

The ring road continues up to the summit, where the land falls away steeply. At the summit there is a small parking bay, along with steps to a concrete viewing platform, trig station and interpretative plaque. A ridge extends from the trig across the top of the mountain in a north-westerly direction. This ridge is grassed and has been planted with trees. It separates the site of the old quarry (now the archery range) to the north from the rectangular playing field on the south side of the ridge.

The road then descends the southern slopes to a larger sealed parking area next to the playing field and opposite an area of land owned by Watercare Services Limited, on which there is a functioning water reservoir. An arm of the reserve extends in a south-west direction below the Watercare land and above residential properties in Mount Royal Avenue.

The playing field is bounded to the north by the central ridge, while a changing shed has been built into a bank on its southern boundary. A second picnic area is set amongst mature trees next to the carpark. Public toilets are situated at the south-west corner of the field. The ring road continues past the carpark and toilets, exiting back onto Summit Drive.

Existing reserve features are shown in Figure 5.

5.2 Geology

Mt Albert - Owairaka�s distinctive geology and topography are the result of volcanic processes operating on the Auckland isthmus over the past 150,000 years and subsequent historical modifications. The result of Auckland�s volcanic activity is a field covering approximately 360 square kilometres which includes approximately 50 eruption centres with scoria cones and tuff craters and 8,000 hectares of basaltic fields.

Volcanic eruptions on the Auckland isthmus followed the same general sequence, resulting in three distinctive volcanic landform types (explosion craters, scoria cones and lava fields) depending on when in the eruption sequence the volcanic activity ceased. Just prior to a volcanic eruption, magma rises towards the surface, encounters ground water or reduced pressure near the surface and explodes in an eruption. Heavier material is thrown horizontally forming a tuff ring, whereas lighter material rises vertically into a mushroom shaped cloud. The presence of these particles in the atmosphere creates instantaneous thunderstorms and rain, which fuels further explosions and builds the tuff ring higher. After the energy is expended in a matter of hours, days or months, water collects in the crater and some eruptions finish here forming volcanic basins. If the activity continues, additional lava rises in the vent and a lava lake may form. If the lava is prolific, fire fountaining occurs which builds a scoria cone(s). These cones coalesce and rise to cover the tuff ring. Lava bursts out of the lower level of the cone and diminishes the fire fountaining. If the outflow of lava continues it can undermine and collapse the cone which is carried away in the lava flow leaving a horseshoe shaped breached crater.

Mt Albert - Owairaka erupted over 30,000 years ago and is described as the remains of a scoria cone, almost burying a tuff ring. It rises to 140m above sea level and about 80m above the underlying ridge of the East Coast Bays Formation. Extensive lava flows issued out around the base of the scoria cone to the west, north and east. The toe of this lava flow forms the Waterview coastline adjacent to the North Western Motorway. Smaller lava flows to the south influenced the current course of Oakley Creek. A scoria rock field is present on the slopes above Mount Royal Avenue.

The natural form of Mt Albert � Owairaka has been altered significantly. Maori occupation of the cone as a pa site involved excavations of features such as terraces and pits. By far the most extensive modifications have occurred as a result of quarrying operations, which began in 1867 and continued until 1929. The total volume of material removed by quarrying has been estimated at 1.5 million cubic metres and has reduced the height of the cone by approximately 15 metres.

Further modifications include the development of a ring road, construction of water reservoirs and provision of a playing field and archery range.

5.3 Flora and fauna

The exact and detailed nature of the vegetation on Mt Albert � Owairaka early last century has not been ascertained. It can be said that the existing plant cover is far removed from the natural condition.

Most of the land area of the reserve is maintained as pasture which is grazed. This is interspersed with planted trees (mostly exotic) occurring individually or in groves. Trees on the outer flanks of the cone are mainly puriri and pohutukawa, with some mature gum specimens. Most of the gums on the northern face of the mountain were felled in the early 1990�s due to a fungal infection of their roots which caused the trees to die back, posing a safety hazard for reserve users and the adjoining residential area. Trees planted around the playing field include flowering cherry, various gums, poplar, willow, olive, coral tree, coast banksia and silky oak. The largest trees on the cone are several holm oaks, a pohutukawa and macrocarpa all located by the playing field carpark. The southern slopes of the archery range are planted with many large mature gum trees, which have been underplanted with totara saplings. There has also been some planting with native vegetation species, including numerous cabbage trees, along the eastern boundary.

The presence of vegetation on the reserve provides habitat for wildlife including a variety of bird species common to the Auckland area. Animal pests are also present with rabbits in particular damaging archaeological sites and landscape features as a result of burrowing activities. See Appendix 3 for a list of flora and fauna.

5.4 Recreation and use

5.4.1 Recreation activities

Mt Albert - Owairaka is a large, grassed, easily accessible reserve, which is used by the both the local and wider community for a variety of recreational activities. Generally the reserve is used by visitors for informal recreational activities including walking, jogging, picnicking and walking the dog. As Mt Albert � Owairaka provides excellent vantage points for viewing the Auckland area, sightseeing is also common.

Active recreation is also provided for by a playing field, which is predominantly used for soccer over both winter and summer. It continues to be used by the Seamen�s Mission, which began using the facility in the 1950�s to provide recreation for the crew of visiting ships, although this use has declined in recent years. It is also well used by schools and clubs who book use of the field for a season. When not in use for organised sports, the field is available for casual use by the public.

The Mountain Green Archery Club is also established on the mountain. The club leases the site of the old quarry for its archery range. This area is also available to the general public when not being used by the club.

5.4.2 Leases and licenses

The Mountain Green Archery Club has been leasing the site of the old tramway quarry, which covers an area of 0.87 hectares, since the 1940�s. The lease applies only on Saturdays and Sundays during the day and includes maintenance of the clubroom. The lease is due to expire on 31 March 2001. The provision of archery in its present location is consistent with the Open Space 3 zoning which allows for organised active sports. There are no other leases on the reserve.

Pastoral farming has been used to control pasture growth on volcanic landscapes for a number of years. On Mt Albert � Owairaka there is an informal arrangement for the grazing of the reserve. This arrangement limits the class and size of cattle that can be grazed on the cone and requires that they be removed during the wettest winter months. Council is responsible for weed control, fertilising and maintenance of fencing, except in instances where cattle have caused unreasonable damage. Grazing is permitted over most of the cone except in fenced tree compounds, on the playing field and a small area near the playing field which contains archaeological sites. A small cattle yard and loading ramp is situated beside the playing field to enable movement of stock.

Council is currently reviewing the grazing arrangements for all its reserves including Mt Albert � Owairaka, in line with the Grazing Policy.

5.5 Access and circulation

5.5.1 Vehicle access and carparking

Vehicle access to Mt Albert � Owairaka is available from Summit Drive. Within the reserve a sealed, one way, ring road provides access to the summit of the mountain. Controls have been introduced to reduce the speed of vehicles. Sealed carparking is provided adjacent to the playing field. An unsealed carpark exists next to the archery range and a small parking bay is provided at the road�s highest point, adjacent to the steps leading up to the viewing platform.

Image 3 Vehicle access from Summit Drive

5.5.2 Pedestrian access and linkages

Pedestrian access to the reserve is provided from Toroa Terrace, Mt. Royal Avenue and La Veta Avenue. All these accessways are sealed but are not signposted from the roads or the reserve. An additional accessway and potential entrance into the reserve, from Grande Avenue is currently fenced off and gives the appearance of being part of a neighbours property. Pedestrian access is also available from Summit Drive with the ring road providing access to the summit.

Within the reserve, there are no formed paths. Informal tracks have become established on the cone, particularly along the sides of the ring road and along the ridges between the road and archery range. Steps lead from the highest point of the road up to the trig station and plaque. Mt Albert - Owairaka also forms an important focal point in the development of walkway networks in the area and across the isthmus.

5.6 Buildings and facilities

5.6.1 Clubrooms and toilets

A small building servicing the archery club is located adjacent to the archery range. The original clubroom burned down in 1957 and was replaced the same year with the existing building. In 1964 an extension was added. There is no power supply to the building.

Changing rooms and showers are provided along the southern edge of the playing field. Constructed in the early 1900�s, they are set into the side of the bank, which is retained by a stone wall.

Two composting toilets are also provided adjacent to the playing field. This facility is well sited to service the field and the picnic areas and is close to the Summit Drive entrance to the reserve.

5.6.2 Furniture and signage

There are two picnic areas located adjacent to the playing field, with seating, picnic tables and litter bins. They are situated in reasonably sheltered and shady positions which also take advantage of views and do not visually intrude on the reserve.

Three information panels are provided on the reserve, at the Summit Drive entrance, the archery field and at the summit. They outline the history of the reserve including the origin of its name, geological history and modifications to the cone as a result of Maori occupation and subsequent activities including quarrying.

5.7 Services and utilities

The two water reservoirs located on either side of the Summit Drive entrance are now no longer used and one has been removed entirely. The only other structure currently located on the reserve is a trig station at the summit.

5.8 Adjoining land uses

The surrounding landuse is predominantly residential. Watercare Services Limited operates a reservoir adjoining the southern boundary of the reserve with vehicle and pedestrian access to the reservoir available from the ring road. The grassed expanse of the reservoir site contributes to the visual amenity and open expanse of Mt Albert - Owairaka and provides opportunities to admire views.

The land surrounding the Mt Albert � Owairaka volcanic cone is zoned Residential 3b in the District Plan. This zoning is applied to residential areas that have a significant relationship with the natural landform of the volcanic cones. Appropriate controls on subdivision and building height are applied to promote compatibility of building form and texture with the character of the cones and preserve views, particularly along designated viewshafts.