Restoring the Porter Brook

Page 1

Porter Park •

Restoring the life of the Porter Brook • Urban ecology is fast becoming a highly relevant topic, as there is an increasing need for more green space within our cities. Green space provides people with a place for recreation, relaxation and has been seen to improve quality of life. Whilst providing a human benefit, these spaces can also contribute to carbon reduction, flood mitigation and a variety of habitats. These habitats can provide for common urban wildlife, but also rarer species that have been declining due to the development of buildings on previous habitat space. Along with the benefits the river can bring, the site in question has a great potential to provide habitats, contribute to flood mitigation, and provide a succesful public space for Sheffield to enjoy.

Conception

Inspiration was drawn from a number of sources encompassing water, natural forms and natural processes. In particular, the process a river has from start to finish as it cuts its way through high mountains onto lower land and then finally spreading wide and vast over coastal areas before entering the sea. Much of the planting inspiration is from natural wetland complexes, as well as the dyamacy wetlands provide come high water levels. A key aspect is the process of succession, inspired by natural successive vegetation systems, and river systems as they come together. The phasing structure is a progressive element that encompasses many other elements, much like the tributaries of a river, and contributes to the success of all aspects of the design.

Aims

•Create a successful public green space •Utilise the Porter Brook for flood mitigation measures •Encourage suitable habitats to encourage greater biodiversity in a highly urban area

Objectives

•Create a wetland complex that allows for flooding of the area and changes seasonally •Establish a permanent structure that benefits the local community through it’s use •Provide an exciting gateway view as you come out of the station •Bring in a large variety of flora and fauna through successionary phases •Connect with the existing green spaces, the Porter Brook and main pedestrian thoroughfares.

Conne

ct

River Strategy

“Ideas, like large riv ers, never have just one source.” Willy Ley

To acheive success in this design, it is necessary for there to be a number of key interventions that allow the various processes to happen. The aim of the river strategy is to: • Cleanse the water through natural processes •Contribute further to flood mitigation •Create a network with the river, other rivers and surrounding green spaces. The two sites illustrated here have potential to be altered. If there is possibility to implement interventions here, then there can be numerous benefits. This shows only the heavily urbanised area of the river, where it has been culverted for many years, Any alterations should take into account further upstream and the connection with Endcliffe Park and the Peak District. Bringing aspects of the local ecology down from the Porter Brook corridor would be ideal to cater for local wildlife populations as well as creating a green connection, public or not.

Matilda St car park

“In merging nature and culture the most successful cities combine such universal needs as maintaining or restoring contact with the cycles of nature, with specific, local characteristics.” ― Sally A. Kitt Chappell,

Decathlon - Sylvestet St car park

There is opportunity for these two sites to cleanse the water and create a large floodplain. This will reduce the risk of flooding for the wider Sheffield area, as well as creating potential new habitats for all manner of wildlife. Specifically, the aim of these site interventions is to increase freshwater fauna populations, bringing down fish from further upstream to more urban areas. This is likely to have a knock on effect, bringing in birds, and is an indicator of a healthy ecosystem.

Enhance Allowing nature through

1:500 plan @ A1

Temporary public space able to be utilised in a positive manner to create attraction to area. E.g, markets, displays, food stalls - all to link in with Sheaf Square and make use of the hard landscape.

Pioneering brownfield vegetation...a few key species These species will form the basis of the vegetation structure as well as others. Wild Fennel Foeniculum vulgare

Pioneer vegetation allowed to grow through succession to create habitat specific to local area. May require general maintenance.

Perennial herb, currently colonising the site peripheries.

Series of wetland ponds which will fill up before flooding, successively. This will be done through sluice gates and careful landform creation. In the event of heavy rain, the surrounding floodplains will capture the water.

Found on dry soils as well as riverbanks, so likely to remain.

Silver Birch Betula pendula

Willowherb Epilobium

Vertical tree, often one of the first trees to colonise brownfield habitats.

Upright perennial that produces striking pink flowers in summer

Currently a few on existing river banks

Phase 1 Establisment of a Framework

Currently exists on site

Public space connected to the river and allows central views to the whole of the site. This will become the primary public space in later phases. Connection to the footbridge over the station has been made possible

AIMS OF PHASE

Purple Toadflax Linaria purpurea Perennial with attractive purple flowers.

HOW?

Key Pioneer vegetation allowed to colonise to create natural habitats, specific to the local biodiversity. This will also act as a flood plain

EFFECTS

Exists currently on site and likely to remain

Temporary space for public engagement, utilising Sheaf Square as well Yorkshire Fog Holcus lanatus

Retention of existing artefact to create a threshold through to the site

Common native grass, can be seen as invasive. Ideal habitat for the small skipper butterfly. (see second page)

Alteration of river course, removing concrete channel and utilising excavated material. Implementation of permanent public space to be used for public events - illustrated later. Building a framework of wooden pathways that allow the vegetation to colonise naturally, whilst allowing public enjoyment of wetland features. These are also floodable.

The beginning phase is to create a framework for the successionary phases. Initial river improvements will be vital in flood protection along with landform changes and excavation work. Vegetation will be allowed to grow naturally, and colonise at will with careful management of some invasive species such as Buddleija and Japanese Knotweed. Ideally, the river will be the main source of seeding and this will help create a species complex that is local in character and identity with the rest of the Porter Brook. It is also necessary to create a public place, so people feel attatched and can enjoy the space, looking at the river and increasing amount of wildlife. LSC 302

Sam Bailey

100182464


Phase 2: Establishment of Infrastructure

1:500 plan @ A1

AIMS OF PHASE

Phase 2 is a continuation of the succession that has been initiated in phase 1. With the floodplain established and the brownfield vegetation encouraged and managed, there needs to be increasing public interest into the site. This is to create a sense of belonging to the site for the people that would use it every day or occasionally.

HOW?

Education is an acheivable way to engage people with the landscape. The temporary structure that will be implemented can be used for this as a museum, possibly orientated towards children. The structure could have many uses, but a museum will allow the public to engage and learn about wetland complexes, urban habitats, Sheffield’s Rivers or anything with reference to the character of the site.

EFFECTS

Increasing activities such as markets, food stalls and events will also increase the success of the site. It is essential to integrate with Sheaf Square and create a buzzing atmosphere to acheive this.

Util

Developing wetland mosaics

ise

There may be potential for some increased management to occur such as coppicing or planting of specific species in plan of future phases.

Increased access and connectivity to CIQ. The steps and platforms down provide a viewpoint across the whole site and a perspective down the river.

Coppicing

Coppiced Salix and Cornus species will create a characteristic feature of carr woodland. Coppicing can be undertaken yearly when the plants are established. The trimmings can be used for fencing elsewhere, or even for energy use.

Island accessible from pathways. Low enough to see and engage with nearby water. Floodable in event of heavy rain.

Temporary structure for use of education about wetlands / ecology / rivers.

Coppiced Salix

Coppiced Cornus Sanguinea ‘ Midwinter Fire

Users 12 year old Main route to school from behind the station Enjoys being surrounded by greenery and wildlife in the brief moment he passes through.

Floodplain Meadow Communities

Open coppiced woodlands will often have an understorey that can be beautiful. Some floodplain meadow communities can colonise these understoreys, but these species can also be planted in this phase if necessary.

Has been on school trips to the museum and learnt about river ecology! 30 year old Market Vendor

Cynosurus cristatus

Comes every weekend to the new market to sell his vegetables and enjoys the atmosphere. He has also taken his children along on a different day to explore the river and surrounding meadows.

Filipendul ulmaria Festuca rubra This photomontage illustrates the connection between the developing public space and the developing riparian habitats. (trees not planted in phase 2, with the exception of the willow which ideally colonises naturally.)

26 year old Commuter Gets the train every week day to Manchester. Admires the view as he walks past, and ventured in a few times to drink coffee when early for a train. Appreciates the green space a lot more than previous waste-land.

Phase 3: Finalisation The third and final phase is the ideal perfect situation, with everything else having gone to plan i.e, success in the public eye, ideal vegetation structure and composition and habitats created.

AIMS OF PHASE

The succesion of the previous phases allows there to now be a magnificent gateway image as you enter Sheffield from the station. This will draw people to the landscape, and fit well with the impressive Sheaf Square water features. As everything will be fully established, the landscape can continue to flourish as season after season as the wildlife, the activity and the weather create the dynamacy to make this a successful landscape.

HOW?

Great Tit

Found in open decidous woodland, mixed forests and forest edges. Common in urban woodlands.

EFFECTS

Insectivorous but does feed on nuts and seed Ecosystem Services: reduces insect numbers

A

A’

Yellow Wagtail Inhabits areas near water, wet meadows. Often spotted ‘wagging’ on rocks in the river

Woodland pathway

Coppiced Salix/Cornus Wetland pond area that and understorey floodplain drains slowly through meadow species. successive ponds.

Insectivorous

Inhabits rough grassland, woodland clearings

Mallard Duck

Main food - Yorkshire Fog.

Inhabit wetlands, so would be suitable in slower moving ponds (see plan)

Recorded further up Porter Brook so ideal if this species came down into urban area.

Omnivorous, including invertebrates and various plant matter - primarily wetland vegetation.

Floodplain meadow. All here (except main path) is floodable with no impacts

Greater Crested Newt

Small Skipper

Ecosystem Services: reduces insect numbers

Central pathway towards main publicspace.

Ecosystem Services: good pollinator Meadow Brown

Inhabits slow moving streams, ponds and pools - ideal for wetland pond areas (see plan). Normally live on land but feed Feeds on other newts, small frogs, insect larvae, worms and water snails. Rarest of 3 newt species in UK and protected by law so brilliant indicator of healthy ecosystem.

Inhabits meadowland - ideal for drier meadow plantings (see plan).

Very adaptable to many environments, but often seen as indicator of successful environment

Similar to island in that it engages public with water. Floodable at high levels.

Feeds on Festues and other meadow grassses.

Bumblebee

Recorded further up Porter Brook so ideal if this species came down into urban area.

Nests directly in the ground among tussocky grasses.

Ecosystem Services: good pollinator

Pollinates a large manner of flowering plants, and found in many urban landscapes.

Small Trout

Indicator of healthy plants

B

Found in most rivers and lakes across world. Recorded in upper parts of Porter Brook. If river strategy implemented, water cleaned and concrete channels removed it could possibly bring this fish into urban areas.

B’

Feed on other fish and aquatic invertebrats such as the watrer cricket (above). Woodland path and bridge leading to island

Island succeptible to flooding. Used for public to get closer to water and wildlife when low water levels. Possibility for picnic area.

River channel. See plan for extents in high water levels

Main pathway to centre

Indicator of healthy rivers. Trout are also prey to herons, so if these are spotted then that is also an indicator of a healthy ecosystem.

LSC 302

Sam Bailey

100182464

Ecosystem Services: very good pollinator


1:250 Masterplan Phase 3 @ A1

Ramp provides access to site and elevated views across it

Main central hub of publicactivity for markets and pop-up cafes etc.

Dry meadow planting including poppies, asters. Banked towards Sheaf Square to prevent flooding

Dry meadow mixes including Papavher, Aster, Coreopsis

Coppiced Salix and alder form barrier from taxi rank Wetland ponds create slow moving waterbodies for habitats. Outlets allow the water underneath main path

C

D’ Glass atrium building allow views through and access into museum below

C’

Salix species coppiced for re-use as material or energy A

A’

Islands allow for greater interaction with water and are connected to the path

Outdoor cafe with views across landscape

D

Alnus a common tree species in wet woodlands. There is both common Alder and Grey Alder on site currently, and it is likely the river will bring more down and colonise.

B’

Outside edges of river designed to cope with high water levels. In event of extreme flood, there is approx. 4500m2 of floodable landscape without impeding on connections or buildings. Riparian vegetation along banks of the river and ponds B

Retention of existing artefact, but removal of ground objects in the way to create a threshold into the site.

Improved access with platforms for viewpoints

Continuation of gold route street furniture - lamposts Green roof ramp accessible from the street Green Roof ramp accessible from the street

C’

C

Floodplain barrier with Path from cenral meadow planting path

Glass atrium for views from street and gateway image from the station entrance

The form of the building and green roof ramp was inspired by the hills and valleys that are cut by the flowing of a river over thousands of years. Planting should be characteristic of dry areas high up the ramp, and merge with the wetland mosaic compositions at lower levels, reflecting patterns that naturally happen over hundreds of miles.

Integration with Sheaf Square - connection through to building

Floodplain barrier with dedcorative planting

Access from road and existing path

Vegetation character extends up the green roof to blend landscape and building.

Prov

ide

D’

Understorey cafe to go along with museum adjacent...

D

..extending outside for views onto landscape Landform change to prevent high water levels reaching building

Sunset from station entrance

From the Porter Brook’s entrance

LSC 302

Sam Bailey

100182464


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.