WELCOME TO TECHNICAL STUDY NATALIE GRAHAM
NATALIE GRAHAM C3305595 PG DIP LANDSCAPE ARCHITECTURE LA705 MAJOR DESIGN LEEDS BECKETT UNIVERSITY
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W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
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W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
Technical Study CONTENTS 1.0 2.0 3.0 4.0 5.0 6.0
Introduction Bradford Beck Management Strategy Hydromorphological Structure + Detailing Softscape Strategy References Appendix
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W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
1.0 Introduction 1.0 Pur pose of t he Repor t T his s t ud y act s as an acc omp anime nt t o t h e ‘ W e lcome to Bradford’ D e sig n & A cc e s s Sta t eme nt ( 2016 ) . T h e re p o r t sh ould b e re ad as a supp o r ting do cument, designed to e x plo re t h e t e chnical asp e ct s o f c re a ting a s t o r mwater management s t ra t eg y t o impr o ve t h e wa t e r quali t y o f sur fac e runoff within the n o r t h e r n e x t e nt o f t h e Brad f o r d B e c k ca t chme nt . The repor t seeks t o pr o v ide a br o ad unde rs tanding o f t h e B e c k as a natural resource u tilis e d t o alle v ia t e f lo o ding t hr oug h t h e re - naturalisation of t h e wa t e r c ours e , t o impleme nt habi ta t c re a tion and enhance the ame ni t y valu e o f t h e pr imar y blu e - g re e n link fr om the city centre to the North. T h e t e chnical s t ud y e x plo re s t h e pr op o s als a t a strategic level; w i t h t h e int e ntion o f pr o v iding an indica ti ve guide for detailed de sig n . T h e re p o r t us e s re s e ar ch and cas e s t udies to inform the manageme nt pr inciple s and pr op o s e d int e r ve ntions, presenting demons t ra ti ve c ons t r u ction de tailing and a s o ft landscape strategy t o s t e e r f u t ure de ve lopme nt .
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THE ARCADIAN
THE URBAN BECK BRADFORD BECK
CANAL ROAD CORRIDOR
FORSTER SQUARE PARK CITY CENTRE
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W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
RIVER AIRE
N BECK
1.0 Introduction LEEDS LIVERPOOL CANAL
1 .1 Aims This re p o r t aims t o e x plo re t h e sus tainable manageme nt of wa t e r using na t ural re s our c e s and e c o s y s t em s e r v ic e s
t h e sur r ounding lands cap e t o manage wa t e r naturally, t o mi tiga t e f lo o ding and e nc ourage int e raction with the wa t e r c ours e in all o f i t s f o r ms . T h e s t ud y presents an o ve r v ie w o f t h e f our charact e r are as ; t h e City Centre; F o rs t e r S quare Par k ( and C anal Ro ad C o r r idor); the Urban B e c k and t h e A r cadian B e c k .
to impr o ve t h e quali t y , ae s t h e tic valu e , f lo o d alle v ia tion
1.1.2 Obj ecti ves
cap aci t y and bio di ve rsi t y o f Brad f o r d B e c k .
T his re p o r t is n o t de sig n e d t o imp ar t a f ull y detailed design p ac k age ; t h e s t ud y int e nds t o pr o v ide an understanding
1 .1.1 Design Int ent
o f t h e pr op o s e d wa t e r manageme nt o f t h e Beck, from City
‘ W e lc ome t o Brad f o r d ’ s e e k s t o rege n e ra t e t h e ci t y o f
C e nt re ( f o r t h e pur p o s e s o f illus t ra ting t h e stormwater
Brad f o r d t o b o o s t t our ism , f o cusing on re - link ing t h e ur b an
manageme nt t rain t o t h e B e c k ) t o t h e n o r t hern extents,
co re w i t h t h e sur r ounding r ural lands cap e t o t h e n o r t h and
w h e re i t c o ale s c e s w i t h t h e Ri ve r A ire . Fur ther advice
we s t , b y br ing ing t h e c ount r y side b ac k int o t h e ci t y .
sh ould b e s oug h t fr om t h e re le vant pr o f e s sionals, sp e cialis t e ng in e e rs and appr opr ia t e p ar t n ers/
Th e C anal Ro ad C o r r ido r is t h e main ar t e r y re c onn e cting t h e
o r ganis a tions . T h e pi v o tal obj e cti ve s are t o impar t:
ci t y t o S al taire , B aildon M o o r and t h e Dale s b e y ond t o t h e
• A n o ve r v ie w o f t h e f our de f ini ti ve are as, outlining the
n o r t h . T h e c o r r ido r is a pr imar y c onn e ction in t h e s t ra t eg y ,
s t o r mwa t e r manageme nt pr inciple s applied that affect
wi t h an e nhanc e d sus tainable t ransp o r t in fras t r u ct ure ,
t h e re sul tant f lo w do w ns t re am .
re v i talis e d B e c k and adj oining g re e nsp ac e . T h e Dale s Way Link , a k e y dr i ve r in pr omo ting t our ism r uns t h e le ng t h o f co r r ido r , as a me ans o f sh o w casing t h e t hr i v ing lands cap e
• A n unde rs tanding o f t h e h y dr omo r ph ological form of the B e c k a t var ious p oint s along t h e le ng t h . • Indica ti ve c ons t r u ction de tails t o in f o r m the detailed
tha t charact e r i z e s t h e ci t y and d y namic a t ti t ude o f t h e
de sig n o f t h e si t e , f o cusing on de f ining site specific
p e ople .
e leme nt s including b ank s tabilis a tion , accessibility, le ve ls and habi ta t c re a tion .
Th e pr op o s al pre s e nt s an aspira tional s t ra t eg y f o r re s t o r ing t h e B e c k t o i t s na t ural f o r m and re ju ve na ting
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• D ominant charact e r - de f ining planting t ypologies along t h e na t uralis e d B e c k .
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[10] CHANNELISED BECK IN DISREPAIR
W E L C O M E T O BRADFORD
1.0
[ TECHNICAL STUDY ]
point s , t he wat e r b o d y is pre dominant l y lac k ing in e c olog ical as s e t s and acc e s s t o t h e wa t e rside is limi t e d . T h e B e c k is clas si f ie d as
Introduction
o f “po o r e c olog ical quali t y ” unde r t h e Wa t e r F rame w o r k Dire cti ve ,
1 . 1 Bradford Beck Catchment
r ipar ian manageme nt .
aff ir ming t he n ega ti ve imp act o f t h e ar ti f icial s t r u ct ure and p o o r
Bradfo rd Beck is th e primary wat e r c ours e in Bradf o r d, w it h a catchment area of 42.978km 2 . T he r ive r is de f ine d by t he
1.1.1 Pollutant s
Env ironmental A gency as “h eavily mo dif ie d”, emphasizing t he
T he wat e r quali t y is c ontinuall y c ompr omis e d b y t h e deg rading
c ons train ed nature of the wa tercours e .
c ombine d s e we r s y s t em unde r pinning Brad f o r d . T h e re are 51 c ombine d s e w e r o ve r f lo w s in t h e ca t chme nt , t hr oug h w hich e x c e s s
T he Be c k is fed b y several tributarie s , mo s t o f w hich are culve r t e d
f lo w s spill dur ing w e t w e a t h e r . A ddi tional s our c e s als o c ont r ibu t e
wi thin the urb an extents of the city, pas sing t hr ough pre dominant ly
t o t he po o r wa t e r quali t y , including illeg i tima t e and mis c onn e ct e d
indus trial areas. Th e natural steep t opography o f t he Bradf o r d
s e w e rs re le asing dome s tic and indus t r ial e ff lu e nt s , r o ad r un o ff
Basin feeds all tribu taries into t he canalis e d B e c k be f o re it
and lit t e r . As so cia t e d wa t e r quali t y anal y sis unde r tak e n in 2012
c onve rges with the River A ire a t Shiple y ( F ig.1.1A) . O ve r t he c ours e
indicat e d high c onc e nt ra tions o f ammonia , har m f ul t o f ish in i t ’ s
o f its 9.98km length, the Beck var ie s signif icant ly in charact e r ,
un-ionis e d f o r m; BOD , w hich de ple t e s o x y ge n le ve ls and pr omo t e s
from the op en meandering form up s t re am , t o t he clo s e d culve r t e d
bact e r ia gr o w t h , and sig ni f icant le ve ls o f chr omium ( A ire Ri ve rs
and bric k lin ed chann els favoured dur ing t he Indus t r ial Re v olution
Tr us t , 2012) . T h e re cur r ing spills and p ollu tant s are de t r ime ntal t o
F IGURE 1 . 1 A : Bradford Beck Catchment and Tributaries Map (Source: Aire
do wns tream . Th oug h th e Beck suppo r t s s ome w ildlif e at c e r tain
t he e c ological quali t y o f t h e wa t e r .
Rivers Trust)
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FLOOD ZONE 3 (1 in 100 or greater annual probability of river flooding) FLOOD ZONE 2 (Between a 1 in 100 and 1 in 1,000 annual probability of river flooding
F IGURE 1.2A: Flood Risk map for Planning (Rivers); (Source: Environment Agency). [12]
W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
1.0
o f t he cit y has re sul t e d in a drainage s t ra t eg y t ha t re lie s h e av il y
f lo o ding . F ig . 1 . 2 A illus t ra t e s h o w f lo o d z on e s 2 and 3 follow the
on t he c ombine d s e w e r s y s t em , placing a g re a t de al o f pre s sure on
c ours e o f t h e B e c k and i t ’ s int e rs e ction w i t h t he River Aire. The
Introduction
sur fac e drains .
cur re nt wa t e r quali t y p o s e s a s e r ious r is k t o public health and
1 . 2 F lo od Risk
T he B e c k has an ave rage f lo w o f 0 . 2 - 0 . 3m 3 / s ( 20 0 - 30 0l / s ) . Dur ing
t h e e c olog ical fabr ic o f t h e B e c k , c ompr omising the safety of the pe r io ds o f sus tain e d rain fall o r e x t reme do w np ours , t h e f lo w ra t e
“There are currently 1,047 properties at risk of river flooding,
can r is e subs tantiall y and rapidl y t o a ra t e o f 0 . 5 6m 3 / s ( 5 6 0l / s ) .
assuming no defences from the one per cent probability flood.
Due t o t he fragme nt e d c ons t r u ction o f t h e cul ve r t s w i t hin t h e c o re
This rises to 1,086 in the future. Climate change will increase the
o f t he cit y, t he c ondui t s var y in s t r u ct ure , are n o t h y dr olog icall y
risk of flooding to property from all sources significantly. Future
e ff icie nt and are in a p o o r s ta t e o f re p air . A s a re sul t a 2k m s t re t ch
regeneration and redevelopment offer opportunities to address the
o f t he B e c k ( 32 h e ctare s ) in t h e ci t y c e nt re is liable t o f lo o ding , on
existing risk of flooding.”
ave rage , onc e e ve r y 10 y e ars . Re cur re nt f lo o ding e ve nt s w i t hin t h e cit y le d t o t he c ons t r u ction o f a f lo o d alle v ia tion t unn e l in 19 93 ,
T he city centre has largely lost th e pre s e nc e o f t he B e c k at s t re e t
signif icant ly re du cing t h e r is k o f f lo o ding in t h e ci t y c e nt re .
le ve l , due to th e heavily urb anised core . T he lo s s o f such a nat ural
H o w e ve r , lar ge are as w i t hin t h e si t e are s till a t hig h r is k o f
as s e t c ombined w ith a distinct lack of gre e n spac e w it hin t he he ar t
as s o cia t e d are as .
1.2.1 Pr imar y M easures B e f o re t h e re s t o ra tion o f t h e B e c k is re alis e d , the deteriorating c ombin e d s e w e r s y s t em and o ve r f lo w s mus t b e overhauled. With t h e ong oing p ollu tion f lo w ing dire ct l y int o t h e Beck, the water quali t y w ill c ontinuall y b e c ompr omis e d , n ega ting the ecological re s t o ra tion . A s e p ara t e s e w e r s y s t em is re c omme nded, segregating f oul e ff lu e nt s and s t o r mwa t e r r un o ff . A ll mis c onn ections must also b e tar ge t e d t o c re a t e a s e cure s t o r mwa t e r s y s t em, with no risk of har m f ul ch emicals o r t o x ins .
1.2.1 Long Ter m St rat egy T h e s t ra t eg y pr omo t e s t h e day lig h ting o f cul ve r t s , to reduce the risk o f f lo o ding . T h e g radual re s t o ra tion o f t h e B e c k by opening up the cul ve r t s and re ve r ting t h e wa t e r c ours e t o i t ’ s o r iginal meandering f o r m pre s e nt t h e opp o r t uni t y t o manage wa t e r na turally, and create a ci t y t ha t w ill n o t onl y c o e x is t w i t h , bu t w ill re ap the benefits of a valuable na t ural re s our c e . “Around 5.4 million properties are at risk of flooding from rivers and the sea, surface water or both in England. Annual flood damage costs for the whole of the UK are estimated to be in the region of £1.1 billion.” (PARLIAMEN T.UK, 201 6)
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2.0 Bradford Beck Management Strategy 2 . 0 Sus tainable Water Management Wate r will be managed at each stage fr om t he cit y c e nt re t o t he c onf lue nc e w it h t he Ri ve r Aire, to cleanse, a ttenuate and slo w t he f lo w o f r uno ff be f o re it re ache s t he Be c k . T he Beck will be restored to act as a f unctioning f lo o d alle v iation s ys t em and k e y acc e ssible, ecolog ical asset to t he cit y.
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Ci ty Centre
Forst er Square Par k ( + Canal Road Cor r idor )
Stormwa ter will be manage d t hr ough a ne t w o r k o f sus tainable ur ban
F o rs t e r S quare Par k w ill f o r m an int eg ral p ar t o f t h e f lo o d alle v ia tion
drainage systems w it hin t he built e nv ir onme nt . T he pre t re atme nt o f r uno ff
s y s t em , w i t h a s e r ie s o f c ons t r u ct e d w e t lands and p onds t ha t b o t h r unoff
w ill filter p ollutants and at t e nuat e t he f lo w , t o slo w t he mo veme nt o f wat e r
and a di ve rsion fr om t h e B e c k w ill f lo w t hr oug h , sig ni f icant l y impr o ving
to conventional drains and t he B e c k .
wa t e r quali t y and pr o v iding mu ch n e e de d wa t e r re t e ntion .
W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
THE CITY CENTRE
RIVER AIRE
The Urban Beck
The Ar cadian Beck
Th e Urban Beck is the wat e r c ours e at it ’s mo s t ope n, acc e s sible f o r m ,
T h e A r cadian B e c k capi tali z e s on t h e e c o s y s t em s e r v ic e s o f t h e lands cap e ,
design ed to sh owcase t he mo veme nt o f wat e r t hr ough t he lands cape using
pre s e nting t h e wa t e r way in i t ’ s mo s t na t ural me ande r ing f o r m . T h e B e c k
natural management pr incipals , mimic k ing t he liv ing lands cape s o f t he
is a have n f o r w ildli f e , and pr omo t e s e du ca tion t hr oug h e x plo ra tion and
surrounding countryside .
int e raction w i t h na t ure .
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Existing Underground Culverted Beck
Exi stin g Pro file
Flood Defence Tunnel
Existing Open Channelised Beck
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THE MIRROR POOL
HILLAM ROAD
FORSTER SQUARE RETAIL PARK
CANAL ROAD
2.0 Bradford Beck Management Strategy 2 . 1 Bradford Beck Re-alignment T he Be c k currently follow s a cours e t hat has be c ome he av ily urbanis e d, frequ ently forcing the wat e r bo dy unde r gr ound. T he rege ne ration offers th e potential to re -mo de l t he s t r uct ure o f t he c ondui t to attenuate flooding b oth w ithin t he cit y c e nt re and f ur t he r do wns tre am to reduce the pressure on t he Valle y Ro ad f lo o dplain, ul timate l y mitiga ting th e outflow to t he Rive r Aire .
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sed P r op o
Form
T he proposal explores p otential rive r re s t o ration c onc e pt s t o be
Culvert opened up with 1:3 graded slope (max) to allow
Existing channel wall retained where necessary, with live willow
applie d a t various locations along the B e c k , out lining t he e xis ting
vegetation to establish on banks for habitat creation and
revetment reclaiming opposite bank to provide vegetative
and pro spective rehabilitated forms.
human interaction. Terraced embankment retains steep slope.
cover and bank stabilisation when constrained by space.
KIN
W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
FRIZINGHALL RAILWAY STATION
RIVER AIRE
VALLEY ROAD
SHIPLEY RAILWAY STATION
NG GEORGE PLAYING FIELDS
LEEDS LIVERPOOL CANAL
Channel wall removed and regraded with maximum 1:3 slope to the
Double culvert fully removed; replaced with naturalised river bed and low
Steep wooded bank regraded on eastern side to allow a wider variety
Bradford Greenway, preserving 500mm existing retaining wall as terrace
stepped banks (1:3 max) to encourage marginal growth, increase biodiversity
of vegetation to flourish and greater variety of fauna to interact with
revetment. Existing western wall maintained due to site restrictions.
and create a more effective floodplain. Allows full interaction with the Beck.
naturalised waterbody. Western edge restricted by topography.
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EXISTING CHANNEL INFILLED TO CREATE BAY AND BACKWATER BACKWATER PROVIDES VALUABLE POTENTIAL HABITAT FOR FISH SPAWNING
2.0 Bradford Beck Management Strategy 2 . 2 River Hydromorphology T he ne w Beck w ill b e the thriving , ec ological c o re t o t he C o r r ido r , abundant w ith flora and fauna b oth re ins tat e d and e nhanc e d. To do s o , the Beck must offer the appropriat e c onditions f o r nat ure t o flourish. The re-establishment of th e nat ural f o r m o f t he B e c k w ill e nable to wa terb od y to suppor t a range o f ne w spe cie s t hat have be e n lo s t or diminished over time. T he re s to ration w ill focus on recreating t he nat ural hydr omo r phology o f a rive r, both in th e physical form o f t he bank s and in t he fabr ic o f the rive rb ed , altering th e d ynamics o f t he wat e r f lo w . T he s t rat egy s e e k s to implement the restoration o f a high qualit y e c o s ys t em , in par ticular, improving th e conditions f o r t r out and t he as s o ciat e d aquatic life.
ISLAND FORMED BY NEW MEANDERING CHANNEL
T he proj e ct w ill restore the meandering f o r m o f t he B e c k t o slo w t he flo w o f wa ter, recrea ting natural habitat s t hr ough t he int egration
BAY OFFERS LOW VELOCITY REFUGE FROM BECK, PROVIDING HABITAT DIVERSIFICATION.
o f bay s and b ackwa ters, riffles, pools and islands ( F IG 2.2A-C ) . T he ins talla tion of vor tex/ fish weirs at e xis ting w e irs along t he le ngth o f watercourse w ill allow fish t o mo ve ups t re am mo re e asily. A hy drolog ical engineer should be consult e d t o as s e s s t he impact o f the flow modifica tion and provide spe cif ic f lo w analysis .
F IGURE 2 . 2 A : Schematic diagram illustrating modifications to enhance the physical structure of the Beck to improve biodiversity.
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W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
RIFFLE Riffles are areas of shallow water in the watercourse, that become agitated running over rocks, increasing the velocity of the flow and aerating the water. These are prime breeding grounds for insects, supplying an easily accessible food source for trout and offering habitat potential for cray fish.
RIFFLE
THALWEG (Deepest water flow)
BAR
RUN The run is the main body of water that runs downstream smoothly, usually home to minnow and other small fish that can not compete with larger species in pools.
RUN
POOL Formed by the increased velocity of the water flowing over the riffle, a deeper, slower flowing pool is created, ideal habitat for trout and allowing organic debris to settle. POOL
F IGURE 2.2B : Delineative section showing the formation of pools and riffles to fluctuate the flow velocity to enhance biodiversity
F IGURE 2 . 2C : Figurative plan view of the meandering form of the Beck with pools, runs and riffles.
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NEW NATIVE WOODL RIPARIAN TREE PLANTING RETENTION POOLS & SWALES
BANK RES
HABITAT CREATIO
WET WOODLAND
REGRADED BANKS & TERRA LIVE WILLOW REVETMENT INTEGRATED REEDBED INCREASED VEGETATION
WATER-RETENTIVE HABITAT IMPROVEMENTS MEANDERING CHANNEL
INCREASED TREE CANOPY DAYLIGHTED BECK DIVERSION REGRADED BANKS & TERRACES POND/WETLAND SYSTEM INFILTRATION PLANTER NETWORK
RECLAIMED NATURE HOTSPOTS INCREASED UPLAND RETENTION
INTEGRATED RAIN GARDEN
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BECK FILTRATION DIVERSION
W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
RIVER AIRE
LAND
STORATION
ON
ACES
LEEDS LIVERPOOL CANAL
3.0 Hydromorphological Structure + Detailing 3.0 Wat er M anagement Int er ventions T h e f ollo w ing p age s e x plo re t h e re ali t y o f manag ing water sus tainabl y and re s t o r ing t h e B e c k . T his chapt e r provides a tas t e o f t h e frame w o r k t o b e impleme nt e d w i t hin the built up e nv ir onme nt o f t h e ci t y c e nt re and sur r ounds , b e fore focusing on t h e na t ural f lo o d manageme nt o f t h e B e c k . T h e plan ide nti f ie s t h e ci t y s cale mo di f ica tions t o natural flood wa t e r manageme nt appr o ach w i t hin Brad f o r d .
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F IGURE 3 . 1 A : Section-axonometric highlighting the benefits of the proposed network of infiltration planters and rain garden managing surface runoff from within the city centre catchment.
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W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
3.0 Hydromorphological Structure + Detailing 3 . 1 T h e Ci ty Centre Management Train T he integra tion of SUDs into th e city c e nt re aims t o maximis e t he po te ntial of ecosystem services to c re at e a s t o r mwat e r chain that sus tainably manages run off a t t he s our c e . T he Cit y C e nt re Management train is defined b y a net w o r k o f inf ilt ration plant e rs and rain gardens (Fig 3 .1 A), which s e e k t o dive r t t he f lo w away from c onventional drainage into a ser ie s o f bio re t e ntion bays t hat v isuall y retain and in filtrate rain fall, ads o r b c ontaminant s and c onve y run off a t a measured ra te to t he ne xt link in t he chain. SCALE: 1:50
Wate r is design ed to flow from on e plant e r t o t he ne xt in pe r io ds o f he av y rain fall, before p ooling in strat egically plac e d rain gar de ns .
F IGURE 3.1B : Detail depicting the construction of an infiltration planter.
T he rain gardens w ill crea te larger are as o f c ontaine d inf o r mal planting within th e urb an core, able t o pr o v ide a c o oling e ff e ct in
t o dire ct r un o ff dire ct l y int o t h e plant e rs and rain gar de ns
N a ti ve planting sh ould b e us e d w i t hin in f il t ra tion planters and
ho t summers, invite biodiversity int o t he cit y and pr o v ide v isual
as a lat e ral sh e e t f lo w , remo v ing t h e n e e d f o r addi tional
rain gar de ns t o pre ve nt any f o re ig n s e e ds b e ing transpor ted
re lie f from a h eavily built up environme nt . Wat e r w ill be re taine d,
drainage inle t s ( and pre ve nting blo c k age s ) and splash b ac k
do w n t h e s t o r mwa t e r t rain , e s tablishing f ur t h e r downstream
allo w the filtra tion and settlement of pollutant s and pe r c olat e int o
re inf o r c eme nt . Ri ve n y o r k s t on e w ill dis sip a t e t h e e n e r g y
and causing damage in na ti ve habi ta t s . E ng in e e re d soil should
the ground in excessive rainfall.
o f c onc e ntra t e d f lo w s and mar k t h e e dge o f t h e plant e rs
c ontain su ff icie nt o r ganic s and nu t r ie nt s t o e ncourage and
as a s e nsi ti ve al t e r na ti ve t o tactile p av ing f o r p e ople w i t h
sus tain vege ta tion e s tablishme nt .
T he city centre is defin ed b y e xt e nsive pe de s t r ian are as ,
v isibilit y di ff icul tie s . C are f ull y p o si tion e d blo c k y o r k s t on e
P lanting sh ould b e ch o s e n t o w i t hs tand b o th marginal
pre dominantly hardscaped from the mir r o r po ol t o war ds t he no r t h.
s e ating w ill pre s e nt an addi tional b ar r ie r t o t h e in f il t ra tion
c ondi tions and dr oug h t , t o sur v i ve t hr oug h ou t the summer
T he I talian Porphyry p aving tha t has be c ome s o ic onic w it hin
plant e r e dge s and pr o v ide an a t t racti ve s e t ting t o appre cia t e
mont hs .
the re tail quar ter and around th e ne w Cit y Par k w ill be pit che d
t he v ibrant planting .
[23]
CANOPY INTERCEPTION
EVAPOTRANSPIRATION
N
IO FILTRAT WATER M R O T S
RETE
NTIO
N
L
MOVA
ENT RE
SEDIM
ION
T ILTRA
TER F MWA STOR
RETE
F
UNOF TER R MWA STOR
NTIO
N
RETE
NTIO
F IGURE 3.2 A: Section-axonometric of Forster Square wetland and wet pond showcasing the natural water management principals utilised to process stormwater runoff before water flows into to the Beck.
[24]
N
N
TIO
EN
RET
W E L C O M E T O BRADFORD
[ TECHNICAL STUDY ]
3.0 Hydromorphological Structure + Detailing
ponds , int o w hich wa t e r is dire ct e d t hr oug h t h e ci t y c e nt re ’ s
Shallo w sh e l ve s w ill b e inc o r p o ra t e d int o t h e w etland margins to
inf ilt ration plant e r n e t w o r k . A di ve rsion chann e l fr om t h e B e c k
aid t h e e s tablishme nt o f mar g inal and aqua tic species (Fig. 3. 2B).
3 . 2 F o rster Square Wetland Par k (Canal Road Corridor)
re dire ct s a me asure d v olume o f wa t e r int o t h e p ar k t o re tain a
Sp e cie s w ill b e s e le ct e d t o c op e w i t h f lu ct ua ting water levels,
F o rs te r Square Wetland Park and th e subs e que nt f lo w o f t he B e c k
c onsis t e nt f lo w o f wa t e r t hr oug h t h e s y s t em , f il t e r ing wa t e r t ha t
t h oug h a minimum le ve l w ill b e maintain e d . T h e wetland will be
along Canal Road form a pivotal area f o r t he s t rat egy. T he sit e w ill
may have be c ome p ollu t e d f ur t h e r up t h e ca t chme nt .
sur r ounde d b y a lands cap e bu ff e r emb ank me nt , to retain water in
re c e i ve runoff from th e city centre and a dive rsion f lo w fr om t he
e x t reme f lo o d e ve nt s and t o br ing ae s t h e tic and ecological value
Be c k to sustainably cleanse and retain wat e r t o alle v iat e f lo o ding
As wat e r f lo w s t hr oug h t h e s y s t em i t is f il t e re d , w i t h s e dime nt s
e ls e whe re in th e city and along the cat chme nt c o r r ido r . T he par k
remo ve d and tak e n up b y na ti ve re e d sp e cie s ( F ig 3 . 2 A ) . T h e w e t
will function as a an dynamic p ark and int egral public spac e , at
pond is de e p, t o re du c e t h e sp ac e re quire d f o r t h e shallo w e r w e t land
Wa t e r w ill f lo w t hr oug h a s e r ie s o f na t uralis tic pools to improve
the fo re front of the sustainable wa ter manageme nt s t rat egy in t he
and remo ve s pollu tant s . T h e w e t land t rap s s e dime nt s , re du c e s t h e
t h e wa t e r quali t y and pr o v ide f ur t h e r re t e ntion b efore returning to
public e y e.
ve lo cit y o f inc oming r un o ff t o pre ve nt e r o sion do w ns t re am and
t h e c ours e o f t h e B e c k in an e x t e nde d , op e n , me andering diversion
remo ve s c ontaminant s . T h e re e db e ds and as s o cia t e d vege ta tion
t hr oug h s e clude d w ildli f e have ns , re j oining t h e o riginal source as a
w ill c re at e an abundant n e w habi ta t t y p e in t h e c o re o f t h e ci t y .
cle an , h e al t h y wa t e r c ours e , able t o supp o r t aqua tic life.
T he space is comp osed of a series o f c ons t r uct e d w e t lands and
WET POND (POLLUTANT REMOVAL)
2000MM MILLBOARD LASTAGRIP PLAS-PRO BOARDWALK IN GOLDEN OAK
400MM RETAINING MORTARBONDED RECLAIMED YORKSTONE RUBBLE WALL REINFORCED CONCRETE CAPPING
+94.03
+94.40
150MM CONCRETE FOOTING TO ENGINEER’S DETAIL
+94.30
TOW +93.20
+93.30
t o t h e si t e .
TREATMENT WETLAND
SEDIMENT REMOVAL REEDBEDS 400MM SAND
400MM SAND AND GRAVEL MIX
400MM ROUGH SAND
600MM MINIMUM CLAY, COMPACTED IN LAYERS
300MM GRAVEL
TOW +93.40 TOW +92.80
+93.00 +92.00
SCALE: 1:120
F IGURE 3 .2B: Indicative section of Forster Square wetland and wet pond (Naturalised spillway and plunge pool not shown)
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