Z AG REB III P R OP OSAL
UNI VE R S I T Y OF B ATH S U S TA I N A B L E CI T I ES M.A R CH D ES I GN S TU DI O 6.1 20 1 9 / 2 0
Mark Kendernay Luca Pizzamiglio Andrea Popescu Sirage Saudi Ibreek María Villalobos Throughout the design process we have been encouraged to keep looking behind the surface and to develop a radical yet sensible vision for Zagreb. We would like to give thanks to the following people whose knowledge and insight has been instrumental to developing this report: BATH UNI VE R S I T Y OF B ATH
Jayne Barlow Anne Claxton Peter Clegg Rupert Grierson Jo Hibbert Andy Jarvis Professor Alex Wright Z AG RE B UNI VE R S I T Y OF ZAG RE B, FAC U LTY OF ARC HI TE C TU RE
Mia Roth Cerina Luka Korlaet Maroje Mrduljas C R OAT I A N A S S OCI ATI ON OF LANDSC APE ARC HI TE C TS
Barbara Klemar C IT Y OF F I CE OF S TRATE GI C PLANNI NG AND DE VE LOPMENT
Ana Magdić Nikola Petković Tomislav Dumančić 3 LHD A R CHI T E CT S
Marko Dabrović Goran Mraović TO BE RE AD I N C ONJU NC TI ON WITH:
Volume I — Research & Analysis Volume II — Process 4
Contents
1
S AVA
2
R A I LWAY
3
M OBI L I T Y
4
PL AC E
5
EDGE
6
L A N D S C A PE
7
R E S OUR C E S
8
M A S T E R PL A N
8
R IVER R EHAB ILITATIO N
22
B R OW NFIELD R EGENER ATIO N
38
UR B AN DESIGN TO O LKIT
44
UR B AN DESIGN TO O LKIT
50
UR B AN DESIGN TO O LKIT
62
UR B AN DESIGN TO O LKIT
72
UR B AN DESIGN TO O LKIT
LIVING W ITH A W ILD R IVER
84
L AYE R E D A N D D I VI D E D C I T Y
C E N T R A L S P INE TO INTEG R ATE TH E CITY
6
N
P L AC E M A K I N G A L ON G T H E S PI N E
UN BL OC K ING TH E UR BA N BA R R IER S
7
1
Sava
8
T H E W I L D R I VE R I N T H E H E A R T OF T H E C I T Y
Throughout much of the nineteenth and twentieth centuries rivers had been encroached upon, regulated to gain energy and to protect from flooding, while often severely polluted. Although this is undoubtedly the result of indsutrial urbanisation, it must not be the only model for urbanised rivers. The Sava is one of the very few clean and natural rivers of Europe — yet it is threatened by dredging, hydropower dams and increasing nutrient pollution. This masterplan starts with the idea of a wild river in the city as a catalyst for an ecological model of modernisation of Zagreb in the twenty-first century.
9
Hybrid flood protection strategy
S AVA , Z AGR EB
S AVA , L ON J S KO P OLJE
BR I N G I N G BAC K T H E W I L D S AVA TO Z AG R EB
S AVA
Although the Sava has been engineered to a great extent on its course in Zagreb, outside the capital it shows the image of an wild and living river. The question at the heart of the masterplan is the following: How can the wild river be brought back to the city?
10
Hybrid flood protection strategy
ZAGREB
Odra River Regeneration
S AVA Q 3,600 m3/s
In the event of flooding on the plains of Odransko Polje, the Odra river slowly carries some of the floodwater and returns it to the Sava at the town of Sisak. Due to the role it plays in the natural drainage of the area, it is key for the river to return a near natural state.
E X I S T I N G S P I L LWAY Q 1,900 m3/s S AVA- O D R A C AN AL
Lonjsko Polje 634 km2
Q 1,900 m3/s FL OW C APAC I TY I NC RE ASE D FR O M Q 1 ,000 M 3 /S
The 90% increase in the flow capacity of the canal is to match the existing capacity of the spillway and to minimise the risk of spilling over the levees within Zagreb, even in a millennial flood event.
TOW N OF S I S A K
Odransko Polje — Ramsar 137 km2
216 million m3 €324 million *
S TOR AG E C A PAC I T Y
E C OS Y S T E M S E R VI C E *
Cost of a reservoir of the same capacity
The Odransko Polje (Odra Field) in its current form is already capable of retaining enough redirected water through the Sava-Odra canal to effectively reduce the risk of flood damage in Zagreb — providing an ecosystem service equivalent to that of a €324 million reservoir. In addition, the functioning floodplain is a critical wildlife habitat supporting one of the highest rates of biodiversity in the entire Danube river basin. To safeguard both the floodprotection capacity and its unique ecosystem, the masterplan proposes to designate the Odransko Polje (Odra Field) a Ramsar protected wetland area similarly to the neighbouring Lonjsko Polje (Lonja Field).
N
Spillway Canal Flood storages Floodplains Urban area Lowland area
11
River phasing
0 E X I S T I N G BA N K S , R I VE R BE D A N D G R OUN D WAT E R CO NDITIO N
1 E X PA N S I ON OF BA N K S
2 R E GE N E R AT I ON OF BA N K S , I N S E R T I ON OF L A N D TO F I L L R I VE R BE D A N D R E- DIR ECTIO N O F STR EA M S
3
S AVA
E C OL OG I C A L , UR BA N R I VE R & G R OUN DWAT E R R E G ENER ATIO N
12
River morphology regeneration
0 E X I S T I N G R I VE R BE D
1 G E OM E T R I C T R E N C H E X C AVAT I ON F R A M E WO R K
2 D I VE R S I ON A R OUN D F I X E D & M OBI L E L A N D F OR MATIO NS
3 N AT UR A L R I VE R BE D R E G E N E R AT I ON
13
300M
Seasonal changes
W IDENED R IV ER R EA LM
J ANUARY
L ETTING TH E R IV ER BR EATH E FEB R UA RY
The rehabilitated river realm is designed to accommodate for the fluctuating water levels throughout the year. The melting snow from the Slovenian Alps in spring and the heavy autumn rain bring increased amounts of water down to Zagreb. This is the natural breathing of the river that is critical to the wetland ecosystem along the Sava.
MAR CH
APR IL
MAY
JUNE
R ETUR NING TO A N UNCO NTR O LLED M O R PH O LO G Y
JULY
While it is not possible to return to the extensive preindustrial wetland, the current situation of the Sava still offers enough room to expand.
AUGUS T
S EPTEMB ER
O CTO B ER
NOVEMB ER
S AVA
DECEMB ER
14
N
EXISTING D ISTANCE BE T W E E N LE V E E S
1870
2020
2030
N
15
River regeneration
L AK E JARU N
D RY- M OU N D G RASS
FL OODPLAI N GRA S S
LA KE B UND EK
S AND & GR AVEL B AR
MIXED DECID U O U S F O R E S T
F R OM ‘ S E VE R I LY M OD I F I E D ’ TO ‘ PR I S T I N E ’
The landscape proposal for the River Sava regenerates and restores its river morphology from “severely modified” to “pristine”. This restoration fills in the gap of the green river corridor in Croatia, reconnecting its natural habitats and ecosystems. At the same time, the proposal safeguards the Sava in Zagreb legislation by matching the protective policies of the Ramsar Convention. This sets a clearly defined target for the landscape regeneration on the Sava, upon which future local planning legislation can aims towards.
S AVA
J AKU Š E V E C R IV E R PAR K
16
S AV IC A
1 KM
N
River biomes
CONTI NUI TY OF BI OME S
The river biomes envisioned are based on those of the Lonjsko Polje’s grassland and alluvial forests, allowing for an uninterrupted wildlife corridor along the Sava at a regional scale.
F LO O D PLAIN G R AS S LAND S H ALLOW G R AV E L BE D R IV E R W E T D E C ID U O U S F O R E S T S AND & G R AV E L BAR
D RY D E C ID U O U S F O R E S T
D RY G R AS S LAND
N
Aerial view of the Sava river realm, looking north towards the railway station.
17
Forest time-line
2 5M
20 5 0
1 5M
20 40 8M
20 3 0 5M 20 23 2M
20 21
0.3 M
20 20
TO G R OW A N AT I VE H A R DWOOD F OR E S T
S AVA
The landscape regeneration of the Sava in Zagreb will take approximately three decades for its young alluvial forests to resemble those elsewhere along the river. To safeguard the process during this period of time, the environmental protection of the Sava and its river realm would provide a legal framework of protection from development.
18
Critically endangered species
Aquila pomarina
AQU I L A POM ARI NA
Sterna albifrons
S TER NA ALB IFR O NS
Charadrius dubius
CHA R ADR IUS DUB IUS
Actitis hypoleucos
AC T IT IS H Y PO LE U C O S
Ardeola ralloides
AR D E O LA R ALLO ID E S
F I G H T I N G E X T I N C T I ON W I T H H A BI TAT R E G E N E R ATIO N
The importance of the Sava river corridor for breeding and migratory birds is internationally recognised. Birdlife International has designated numerous Important Bird Areas in the largest bird reserve in Croatia. The Sava basin hosts 6 endangered species — some of which breed only along the middle section of the Sava. These are, but not limited to: little terns, little ringed plovers, sandpipers, squacco herons and spotted eagles. Shockingly, in some of the cases, the count only reaches about 15-20 pairs in the entire river basin. The proposed river regeneration would provide a crucial precedent for the protection and restoration of wildlife habitats in the Danube river basin.
19
N
Crossing the Sava
S AVA
A 40-minute walk from the housing estates of Novi Zagreb to the central railway station, across the rehabilitated riverscape of the Sava.
20
21
2
Railway
BR OW N F I E L D R E G E N E R AT I ON
The railway with its extensive brownfield just south of the city centre effectively cuts Zagreb in half. Connecting the city to neighbouring capitals, Vienna and Budapest, the Zagreb railway station has played a key role in the city’s growth and development. Sitting on top of 4.5-metre tall mounds, the rail is a physical barrier between the nineteenth century core and the post-war development to the south of the station. Only less than a handful of underpasses offer connection, often flooded due to heavy rainfall.
Reversing the hierarchy
E X I S T I N G H I E R A R C H Y OF R A I L OVE R PE D E S T R IA NS
R E VE R S E D H I E R A R C H Y, PE D E S T R I A N S H AVI N G PR I OR I T Y AT G R O UND LEV EL
R AI LWAY
T R AC K S B U R I E D UN D E R G R OUN D , S TAT I ON R E - I M AG I N E D A S A G AT E WAY E N ABLING A N ACTIV E G R O UND PLA NE
24
T H E R A I LWAY S TAT I ON A S G AT E WAY TO C E N T R A L Z AG R EB
25
Operational feasibility
4 00M
400M
400M
600M
20 0 M
OPE N SLOPE
LAND S CAPE OVER TR ACKS
LEVEL PLATFO R M
LAND S C APE OV E R T R AC KS
O PE N S LO PE
UN I N T E R R UPT E D PA S S E N G E R S E R VI C E D UR I N G C ON STR UCTIO N
Burying the tracks below ground is a significant infrastructural undertaking, and interrupting the rail service for the length of this period would be infeasible. It is for this reason that the operational tracks will run through the existing service tracks whilst the construction takes place. The red zone indicates the allocated construction site, and the blue line identifies the tracks which will operate as usual.
R AI LWAY
Demolition Zone
Operational Rail Tracks
26
Temporary Platforms Site
R A M PI N G T R AC K S 1 :1 00 | 8 00M
STATIO N LE V E L AT -8M | 4 0 0 M
T R AC K S UN D E R R A M PI N G L A N D S C A PE 1: 100 | 400M
R A M P A N D PL AT F OR M L AYOUT
To reduce the scale of the construction, the platform level of the new underground station is kept at 8 metres below ground, while its length is limited to 400m — benchmarked to accommodate for the longest high-speed trains currently entering operation across Europe. With the dropping of the tracks below ground, the northern and southern sides of the city centre are re-connected on street level along 1,200 metres.
27
Phase I J ACKED B O X TUNNEL CO NSTR UCTIO N
Demolition, piling, top foundation
E X I S T I N G CON D I T I ON
Operational and service tracks form a physical barrier in the city
STEP 1
To minimise disruption to the passenger trains, temporary platforms with stairs and walkways maintain access to the trains while the existing platforms and canopies are demolished.
STEP 2
Top-down construction, piles are put in place first.
STEP 3
R AI LWAY
Top foundation is placed over the piles.
28
Phase II JACKED B O X TUNNEL CO NSTR UCTIO N
Excavation, public realm, fit-out
STEP 4
Once top-down excavation is started, public realm and landscaping above begins.
STEP 5
Excavation finished, foundation forms final tunnel piece.
STEP 6
External structure of the tunnel completed, fitting out being carried out.
STEP 7
Tunnel complete, tracks fully operational with active and permeable ground plane.
29
Construction sites
4 00M
400M
400M
600M
20 0 M
OPE N SLOPE
LAND S CAPE OVER TR ACKS
LEVEL PLATFO R M
LAND S C APE OV E R T R AC KS
O PE N S LO PE
C ON S T R UC T I ON S I T E S ON PR OPOS E D PL OTS
Due to the scale of the construction works, the logistical issue of PLANNED managingAVAILABLE mechanical equipment must be addressed. TheBUILT land on which PROPOSAL CONSTRUCTION SITES new buildings are proposed is currently brownfield and will be cleared prior to re-development. These sites — highlighted in red — will serve as storage for materials and equipment. Following the completion of the new railway, building construction may begin.
R AI LWAY
Storage Sites
30
Proposal
4 00M
400M
400M
600M
20 0 M
OPE N SLOPE
LAND S CAPE OVER TR ACKS
LEVEL PLATFO R M
LAND S C APE OV E R T R AC KS
O PE N S LO PE
600M OVERGROUND S LOPE
600M ACTIVE 300M FLAT 600M AC T I VE GROUND LEVEL PLATFORM GROUND LE VE L N E W C ON N E C T I ON S T H R OUG H A N AC T I VE L A N DSCA PE
The station, previously seen as a physical barrier, is now re-imagined as an enabler. A gateway allowing not only the extension of the CREATING NEW CONNECTIONS OVER AN ACTIVE LAN D S C APE eastern wing of the “Green Horseshoe”, but also offering a linear park connecting the university quarter to the east and the new business area to the west. The proposed transport project lies at the heart of redeveloping the largest central brownfield area of Zagreb while maintaining a uniquely local blend of late-nineteenth century, post-war and industrial characters in its neighbourhood.
Soft landscaping
Proposed buildings
31
Railway station
60 0 M OVE RGROU N D S LOPE
Sectional conditions
GR A D E L E VE L C ON D I T I ON - D I R E C T R E L AT I ON S H I P BE T W E E N O PPO SING STR EETS
L E V E L D I FFER E N C E - TOPOG R A PH Y I N T E G R AT E D AT F I R S T F L OOR , C R EATING VA R IED TH R ESH O LDS
R AI LWAY
B E T WE E N B U I L D I N GS - L A N D S C A PE S T E PPI N G D OW N TO E X I S T I N G L E VE L S TO C R EATE VA R IED UR BA N TO PO G R A PH Y
32
T R ANS F O R M E D R AILWAY S TATO N
PR OPOS E D L I N E A R PA R K A BOVE T H E R A I LWAY
33
R AI LWAY
34
NOV I ZAG R E B
S AVA R IV E R
T R ANS F O R M E D R AILWAY S TATO N
H IS TO R IC “ G R E E N H O R S E S H O E ” PAR K
BAN J E LAČ IĆ S QU AR E
ZAG R E B C AT H E D R AL
PR OPOS E D L I N E A R PA R K A BOVE T H E R A I LWAY
35
Gateway to Zagreb
R AI LWAY
The railway station is a true architectural heritage of the capital, symbolic of the growth and development the railway had brought to Zagreb during the industrial revolution. With the moving of the rail tracks underground, the station building is transformed as an open gateway to central Zagreb.
36
37
3
Mobility
PUBL I C T R A N S POR T TO C ON N E C T N OR T H A N D SO UTH
Between the two primary barriers is the central axis. Once a display of grandeur by modernist planners, it now remains a vertical barrier in the city. Congested with eight lanes of traffic in peak working hours, the central axis exacerbates the traffic issue in the city. As locals travel north to the commercial heart of Zagreb, the railway cuts off the highway, forcing cars to redirect to the outer ring of infrastructure. This, combined with the lack of underpasses, frequently paralyses mobility within the capital.
Roads as urban arteries EXISTING
I N N E R - C I T Y D UA L C A R R I AG E WAY S
Due to the low number of underpasses crossing the railway (area marked in red), cars redirect into the outer ring road to enter the city, rendering the dual carriageway in the central axis of the city redundant. Despite the extensive public transport network, wide roads built under the modernist planning of Zagreb encourage car use on a daily basis — leaving the active historic centre of Zagreb congested and polluted.
M O BI LIT Y
Major roads
Railway
40
Tram network
North-South tram link PR O PO SED
E S S E N T I A L C A R - F R E E L I N K BE T W E E N N OR T H A N D SO UTH
Marked as redundant for car traffic, the central axis is re-imagined as an essential public infrastructure link between the northern and southern parts of Zagreb. This link consists of two new tram routes, cycling paths and ample pedestrian walkways. At the heart of the problem – the railway station – is now a seamless link for locals to enter the city in less time than previously available. The tram culminates in the south by connecting to a park and ride, before diverting to the proposed Jakusevec River Park and the international airport.
Major roads
Railway
41
Tram network
Public transport network PR O PO S ED
M O BI LIT Y
S AVA TR AM LINK
EXIS TING TR AM LINES
42
B US LINES
R AILWAY
The new Sava Tram Link PR O PO SED
R AI LWAY S TAT I ON
C OAC H S TAT I ON
J A K UÅ E VE C R I VE R PA R K
PAR K & R I D E
ZAGREB AIRPORT
N
NEW S AVA TR A M LINK
NEW AIR PO R T EXPR E S S
43
4
Place
A D I VE R S E C I T Y TO F I L L T H E VOI D
Although there are existing services and points of interest along the locale, they are hardly considered destinations given their poor connections to public infrastructure. With the proposed Sava Tram Link, tram stops will be adjacent to key destinations activating the street frontage. At the same time, mixed used programmes are proposed alongside existing services, diversifying the current zonification of the city. The aim is to holistically increase the activity of the city across all neighbourhoods. The masterplan starts with the central axis, which activates a small part of each.
E X I S T I N G S E R VI C ES / Z O NED CITY
Zagreb is characterised by a disconnection of city services as a result of the ‘layered’ nature of its urban evolution. There is a strong sense of place in the historic imperial city, given by the cultural, civic and academic buildings in the horseshoe. This mixture of services is relatively close to medieval Kaptol and Gradec, creating a relationship between the two that reinforces the upper axis of the city. South of the railway this axis and sense of place is lost, with only punctual large cultural buildings. This area is dominated by informal housing with no sense of public realm. South of the river services are again disconnected and offer little variety.
Residential Office & Workplace Civic Cultural Education Sport & Recreation
PL AC E
N
46
E X I S T I N G S E R VI C ES WITH NEW- BUILT PR O PO SA L
The proposal aims to infill the mentioned voids with a variety of services to bring diverse activity to the vertical axis and to strengthen the role of it as a ‘spine’ for the city that ties together the fragmented historical layers. All buildings along the vertical axis will provide mixed use or retail at ground level to activate the public spaces in front of these. Special attention is given to the existing public spaces in front of important buildings. These spaces are currently underused partly due to them not being appropriately contained or for the absence of public services nearby. South of the Sava, the same principles are applied only at a larger scale, where there is much more void to infill. North and South are connected by the pedestrianised bridge over the Sava. Residential Office & Workplace Civic Cultural Education Sport & Recreation N
47
M A S T E R PL A N R E S ULT
The result of this approach is to achieve a densified vertical spine which reinforces the characteristics of each historical layer, rather than homogenising the whole. The strategy to define the urban block is inspired by the evolution of the urban blocks from the Austro-Hungarian period, whereby a perimeter block was established to contain the more informal arrangement of buildings. Along the vertical spine, an edge is established to define the street and reduce it to a more manageable human scale; on the back of this edge, where the existing residential buildings coexist in informal arrangement, the proposed buildings adapt their form to contain a larger block that is more clearly defined.
Residential Office & Workplace Civic Cultural Education Sport & Recreation
PL AC E
N
48
T R A M S TOPS
G L AV N I K O L O DVO R MIN IS TAR S TVO P R AVOSUĐA AU TO BU S N I K O L O DVOR
VATR O S L AV L IS IN S KI
U L . G R ADA V U K OVAR A
N AC IO N AL N A I S V E UČ I LI ŠN A KN JI ŽN I C A
MO S T S O L O BO D E
G R AD S K I PAR K BU N DE K
U L . DAMIR A TO ML J A N OVI C A
AV E N IJ A D U BR OV N I K
IS L AN D S K A U L .
49
5
Edge
A M OD E L F OR T H E BUI LT PR OPOS A L
The perimeter block, characteristic to Zagreb, transformed the city in the nineteenth century, and is an urban typology still relevant today due to its dense, low-rise structure. As the city has grown following a wide variety of typologies after the inter-war years, the open block model developed in the masterplan aims to densify the urban patchwork south of the railway.
Fragmented city
PATC H WOR K OF D E N S I T Y & S C A L E
E DG E
The city of Zagreb is characterised by a series of contrasting and conflicting scales. As historical events and regime changes had left many urban projects unfinished after 1918, the majority of the capital south of the railway lacks consistency in building scale and density — single storey detached houses often face modernist slabs, while the wide roads effectively cut off neighbourhoods from one another.
52
Integrated city
D E N S I F Y I N G T H E VOI D BE T W E E N N OR T H A N D SO UTH
The north-south spine of the masterplan aims to integrate the typological patchwork. The built proposals are inserted into the urban fabric to mediate between the varying scales and densities. As a supersized diagram of surgical urban infill, the focus of the masterplan is not to create an isolated piece of city but to integrate and densify the core of Zagreb.
53
Zagreb perimeter block
P E R I ME TE R BLOC K
E DGE PO R O S ITY
DEFINED CO UR TYAR D
O P E N BLO C K
BUI L D I N G UPON A L OC A L T Y POL OG Y
E DG PL ACEE
The urban block for the masterplan takes precedent from Zagreb’s native urban typology – the perimeter block. In this way, the proposed buildings can provide order to the existing grain of informal settlements, while providing a shared public space between both parties. At the same time, the permeability of the block prevents the proposed buildings from becoming a physical barrier to the low-rise existing buildings. From this permeability the masterplan also proposes public destinations within the blocks, as is the case in the vernacular Zagreb block. In this way, the masterplan imagines a seamless pedestrian movement between the urban grain of the city, which lies in stark contrast to the found condition in the capital.
54
PU BLIC D E S T INAT IO NS
TO ZAGR EB FAIR
TO KAJ ZE R IC A
S O U T H O F T H E R IV E R
The new residential neighbourhood proposed south of the Sava applying the model of the open Zagreb block. N
TO N OVI Z AGRE B
TO ZAG R E B C E NT R E
TO J AKUÅ EVEC
55
Responsive densification
U RBAN I SI N G TH E I N FO R MAL S P R AWL
In Zagreb’s native urban typology — the perimeter block developed in the late nineteenth century — housing is arranged in an enclosed rectangle while some buildings pre-dating the perimeter planning are retained within the courtyard. Following this model, the proposed buildings of the new pedestrian avenue define open rectangular blocks, where both existing and proposed buildings contribute to the urban form. It is important for the existing small-grain sprawl to be strengthened and serviced by the new-built — the tabula rasa clearing of suburban Zagreb for redevelopment is not only unfeasible due to its scale (planners in the 50’s and 60’s attempted the complete re-planning of the area but effectively ran out of time and money), but it is also an environmentally unsustainable practice. Existing buildings of at least two storeys with habitable roofs, and in good state, are proposed to be retrofitted.
E DG E
EX I ST I NG
D E MO L ITIO N
P E R IME TE R E D G E 56
A DD N E W- BUI LT
AC T I VE ZAGR E B BLOC K
Neighbourhood densification
UR BA NISING TH E INFO R M A L SPR AWL
Similarly to the densification approach at the level of an individual block, the proposed buildings strenghten the edges of the neighbourhood and provide important public realm and services at street level. This aims to reverse the process of this inner-city sprawl becoming increasingly unattractive due to the lack of amenity and services. In the long term, this model of densification encourages a redevelopment of the sprawl that is gradually growing from the new-built edge — an approach where existing and new-built are compatible and complementary.
EX I S T I N G
D E M OL I T I ON
PE R I M E T E R E D G E 57
A DD NEW- BUILT
ACTIV E LO CA LE
Active locale
00:00
Cu lt
t
arke
c
6:00
Ca fĂŠs
Ci vi
vic Ci
ts uran a st
liverie De
P
ostM
18:00
ites ctiv a al r u
s
Nig
htl Extra-cu if Activite rricu s lar e
Tr am
W or Sc k h
Re e
S
den l ergar ooKind vice er
Ser vic
12:00
AC T I VI T I E S T H R OUG H OUT T H E DAY
E DG E
The active locale strategy aims to bring a mix of activities to the new north-south avenue, ensuring that the neighbourhoods it connects have adequate public services — integrating civic, cultural, educational and recreational uses with the predominant residential buildings.
58
Active neighbourhood CASE S TUDY
Proposed North-South avenue TO THE SAVA RI VE R
TO T H E R AILWAY S TAT IO N
PR O PO S E D BU ILD ING S
Residential Office & Workplace Civic Cultural Education
O N S LAVON SKA AV EN U E
59
N
T RA F F I C R ED U C T IO N
Sport & Recreation
E DG E
N
60
N
61
6
Landscape
T H E G R E E N L UN G S OF Z AG R E B
The landscape strategy builds upon the Sava rehabilitation and proposes to transform the locale’s predominantly impermeable surfaces as green landscaping and sustainable drainage.
Problem
I M PE R M E A BL E S UR FAC E S
LA ND SC A PE
It was clear from the research and analysis that the public realm, as well as the existing blue and green infrastructure, are lacking important elements. At the same time, the large amount of impermeable surfaces make parts of the city prone to surface flooding, and allow polluted run-off to drain to the Sava. The result of this is especially critical at the underpasses underneath the railway, which bottleneck transport within the city when flooded in heavy rain.
64
Solution
T H E ‘ S PON G E ‘
The proposed landscape above the buried railway in the city centre, together with the rehabilitated riverscape at a larger scale, function as urban sponges to retain and filter the water run-off. Naturally, a series of creeks would carry water from the Medvednica mountains to the north of Zagreb to the Sava — these, however, have been lost or covered under the historic centre. Although uncovering them may be unfeasible due to the urban density, these creeks provide a local model for sustainable urban drainage.
65
Railway underpasses EXISTING
F L A S H F L OOD I N G OF UN D E R PA S S E S
LA ND SC A PE
The existing condition of the underpasses causes flooding due to the high impermeable surface coverage. With the increased regularity and severity of storm and rainfall brought by the changing climate, these bottlenecks would more and more impact on the daily functioning of the capital. At the same time, their scale separates important public spaces in the capital.
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Railway underpasses PR O PO SED
S HARE D SU RFAC E
U N I NTE RRU PTE D PE DE STRI AN & CYC LE PATHS
H E AV Y R AINFALL S OAK-AWAY S
R E CRE ATI ONAL PONDS
PR O PO S E D R AILWAY PAR K
PE R M E ABLE PAV ING
R A I N FA L L R E T E N T I ON A N D R UN - OF F F I LT E R I NG
The proposal is to reinstate some of the landscape native to the plains of the Sava, in order to allow for a ‘sponge’ to soak up rainwater when heavy rain falls. The mix of ponds, marshlands, trees and other types of planting would also form an important habitat for urban wildlife.
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Locale EXISTING
D I S F UN C T I ON A L UR BA N G R E E N E RY
LA ND SC A PE
The existing green areas along the central avenue are disfunctional both as public realm and soft landscaping. They are cut off from the surrounding residential neighbourhoods by the wide roads, and the lack of integration between the greenery prevent any effective drainage.
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Locale PR O PO S ED
P R O POSE D BI ODI VE RSE ROOFS
S U R FAC E R ILL
S WALE
S H AR E D R AINWAT E R TANK
G E O -C E LLU LAR WAT E R S TO R AG E BE LOW PE R M E ABLE PAV ING
H E AV Y R AINFALL PO ND S /R E E D -BE D S
PE R M E ABLE PAV ING F O R T R AM / S H AR E D S U R FAC E
S LOW R E LE AS E TO R AINWAT E R S E WAG E
F UN C T I ON A L G R E E N PUBL I C R E A L M
The disfunctional green strip of the central avenue is converted into a network of SUD strategies combined with recreational green public space. The low ground water levels are stabilised, while the trees and wetland areas create a varied habitat for the fauna and flora. Several rainwater collection points, channels and pipes are integrated into the underground layers to allow water re-use for plant irrigation along the spine.
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Landscape detailing
I N T E G R AT I ON OF S E R VI C E S
LA ND SC A PE
The organisation of the streetscape elements varies depending on the width of the strip of the avenue — giving space for moving and shelter for staying. The timber bridging, as well as the pavement material are suitable for cycling and running while maintaining a porous surface.
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Native tree species
60 m
45 m
30 m
15 m
Sessile oak S ESS ILE OA K
Common beech CO MMO N B EECH
Quercus petraea
Agus sylvatica
Quercus petraea
agus sylvatica
Pedunculate oak NIAN or Slavonian oak SLAVO OAK Quercus robur
Quercus robur
60 m
45 m
30 m
15 m
Spruce Picea omorika
Silver fir
Black pine
Black alder
S PR UCE
Abies alba SILVER FIR
nigra B Pinus LACK PINE
Alnus glutinosa BLAC K ALD E R
Picea omorika
Albies alba
Pinus nigra
Alnus glutinosa
W H E R E T H E M OUN TA I N M E E T S T H E A L L UVI A L F O R EST
The trees proposed in the masterplan are native to the Croatian section of the Sava river and to the Medvednica mountains north of Zagreb. The new north-south avenue of the proposal creates a bridge between these two ecosystems where the city has previously cut off the environmental connection.
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7
Resources
A CLEAN AND RESILIENT CITY
The resource strategy for the masterplan prioritises a diverse supply of renewable energy sources for the city. In the first instance, the proposal suggests a phasing-out of fossil fuels with an Energy from Waste facility. This is to simultaneously tackle the excessive illegal waste dumps while providing an alternative energy source for the city. Subsequently, new infrastructure is put in place for the distribution of electricity, heating and cooling from solar, wind, and geothermal energies. The diverse supply of energy renders the marketed hydropower projects as unjustifiable. At the same time, the construction of new infrastructure will also replace the leaky pipework of the city’s water supply, securing Zagreb’s clean groundwater from further pollution and loss.
A void in the middle
R ES O U R C ES
The existing condition found in Zagreb concerning resources is a system of disconnected energy facilities, heavily reliant on fossil fuels and hydropower. At the same time, the centre of the city did not have appropriate services, leaving almost 100,000 people without water, electricity and insufficient waste collection. This culminates with the pollution of the city and depletion of groundwater resources.
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Integration of services
The masterplan proposes to fill in the missing void with renewable energy sources and a fully functioning water supply network, reducing the energy demand and carbon footprint of the locale while securing sufficient and clean drinking water. At the same time, the proposal plugs into the existing energy supply network from de-commissioned thermal plants to distribute renewables at a city-wide scale, allowing existing buildings to also benefit from a sustainably power supply.
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Trash to cash
C H A N G I N G T H E PE R C E PT I ON OF WA S T E
R ES O U R C ES
The first phase of the transition from fossil fuels to renewable energy is collecting the city’s excessive rubbish to power its buildings. The Energy from Waste facility is proposed next to one of the decommissioned thermal plants, and as such, can plug into the existing supply network. This allows for an immediate switch from fossil fuels to a more renewable source, while providing an immediate solution to the city’s excessive solid waste pollution. This is not, however, a solution to waste production. To discourage sending more waste to landfill, recycling incentives are put in place which encourage locals to exchange recycling with transport tickets, offers from shops, among others. This promotes exchange of local businesses, stimulating the economy, while provoking more use of public transport.
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WAST E ST R AT EGY
Energy from Waste 3 8 0 ,40 5 T O F WA STE / YEA R
53 MW 142 MW
E LE C T R IC IT Y C APAC IT Y D IS T R IC T H E AT ING
15% O F H O M ES H EATING 43% O F H O M ES POWER ING
With the amount of waste dumped into the landfill annually, 15% of all homes in Zagreb could be powered with electricity and 45% of all homes could enjoy district heating and cooling. While the primary goal is to reduce waste production, the proportion of renewables in the city’s energy mix is so low that waste cannot be discarded in the phase-out of fossil fuels.
Waste collection R ECYCLING INCENTIV ES EU H O R IZ O N
FUNDING
20 20 EM POWER
/ SUPPO R T
PAY A S YO U TH R OW PO INTS M O DEL
PRI M ARY
SECO NDARY
R ECYCLING CENTR ES
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PR O PO S E D E NE R G Y F R O M WAS T E PLANT
N
Safeguarding the groundwater
WAT E R S T R AT E G Y
R ES O U R C ES
A new water distribution network is proposed in the masterplan, filling in the gaps of the existing pipework system, while fixing sewage leakage and drinking water loss. At the same time, a separate rainwater collection network is proposed to prevent the city from continuing to mix rainwater and sewage. This rainwater can then be used to supply water for irrigation during potential summer heat waves and droughts. While the installation of new pipework involves intensive construction, district heating and cooling infrastructure can be introduced simultaneously. In addition, a new drinking water pump is proposed near the rehabilitated river realm.
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WAT ER ST R AT EGY
Trigeneration CO O LING , H EAT & POWER via energy from waste
EX I STI NG PI PE
E X I STI NG PU M P
PR O PO S ED PIPE
PR O PO S ED PUMP
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PR O PO S E D E F W
133,600
4 3 % O F ALL H O M E S IN ZAG R E B
8,000
10 0 % O F NE W H O M E S IN T H E M AS T E R PLAN
PR O PO S E D C O M BINE D C O O LING & H E AT
N
An integrated system
ENER G Y INFR A STR UCTUR E SPINE TRI - GE N / CCHP E FW COO L I NG HE ATI NG P OW E R
MUNI C I PAL SOLI D WAS T E 416 KG / P ERSON / Y EAR
LO CAL HEAT PUMP FO R B A LANCED NETWO R K O F 40°C
WAT E R
H E AT & CO O LING
ELECTR ICITY
R A INWATER
EFW
EFW
HAR VESTING
GEOT H E R M AL
W IND G E OT H E R M AL
POW E R I N G T H E Z AG R E B BL OC K
R ES O U R C ES
The Zagreb block that has been taken as a model operates as a single unit within the locale, collecting and distributing resources among the buildings of the block. In this way, any existing building within the block can benefit from the proposed infstructure upgrade.
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ENER GY ST R AT EGY
Electricity ENER G Y FR O M WA STE
47 M W
G EOTH ER M A L ENER G Y
PA NNO NIA N BA SIN
WIND POWER
Heat & cooling ENER G Y FR O M WA STE
125 M W
G EOTH ER M A L ENER G Y
PA NNO NIA N BA SIN
Solar PH OTOVO LTA IC PA NELS localised energy production
20%
O F NE W -BU ILT R O O F AR E A C OV E R E D
41,100 m2
PV AR E A
1,275 kWh/m2
Y E AR LY AV E R AG E
Enough capacity from other sources that render the ecological damage caused by hydropower unjustifiable.
L OC ALE E X TE NT
R O O F A R EA COVER ED B Y PHOTOVO LTA ICS
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HEAT & C O O LING
E LE C T R IC IT Y
N
Reclaimed materials
R ECYCLED B R ICKS F R O M R AILWAY B UILDINGS B EYOND R E PAIR
E X C AVAT E D G R AV E L AND C LAYO U S S O IL F R O M S AVA-O D R A C ANAL
R E US E D BR I C K S
R ES O U R C ES
As some of the former service buildings around the railway brownfield are beyond repair, their demolition will nevertheless provide bricks to be recycled in the proposed masterplan. An estimated amount of 1,825,000 bricks may be reused in the form of reclaimed brick or crushed for limecrete or paving.
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From waste to construction material
INCINER ATO R B OTTO M ASH ( IBA) F R O M T H E E NE R G Y FR O M WA S TE PLA NT R E C YC LE D AS AG G R E G AT E
EXCAVATED GR AVEL FR O M SAVA-O D R A CANAL
LO CAL LIME S O UR CE
LIM E C R E T E & AS H C R E T E
A BR E AT H A BL E , L OC A L M AT E R I A L
Since most of Croatia’s lime quarries are located along the coastline, other possible locations where less limestone can be found have been relatively underused. This is the case with the limestone quarry to the north-west of Zagreb, Podsusedsko Dolje, where both calcite and dolomite can be found. Incinerator bottom ash (IBA) from the proposed energy from waste plant may be recycled as aggregate.
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8
Masterplan
M AS T E R PLAN
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87
N
20 0 M E T R E S
Masterplan area schedule
ZAGR EB M A S T E R PL AN TOTAL S
S O UTH O F R AILWAY
P R OP OS A L
PR O PO S AL
T Y P E OF U S E
FLOOR ARE A (M 2 )
TYPE O F US E
FLO O R A R EA (M 2 )
Residential Retail Office / Workplace Education Civic Sport Culture
565,345 96,350 261,730 92,135 7,850 22,750 26,220
Residential Retail Office / Workplace Education Civic Sport Culture
99,145 40,285 176,130 46,600 7,875 13,850 22,800
S U R FACE
ROOF ARE A (M 2 )
Total roof area Biodiverse roof area PV area (target 20%)
205,500 164,400 41,100
P OP U L AT I ON GROWTH
Total residential area Floor area / dweller No. of new residents
565,345 m2 25 m2 22,600
POPULATI ON GR OWT H
NO R TH O F SAVA PR O PO S AL TYPE O F US E
FLO O R A R EA (M 2 )
Residential Retail Office / Workplace Education Civic Sport Culture
155,725 28,425 39,700 12,400 0 900 0
NOVI ZAGR EB — S O UTH O F S AVA PR O PO S AL
P HA S E I N EW R E SI DE NTS
2 2 ,600
2035 P HA S E I I N EW RE SI DE NTS
2 0,000
2045
M AS T E R PLAN
TOTA L N E W R ESI DE NTS
4 2 ,600
TYPE O F US E
FLO O R A R EA (M 2 )
Residential Retail Office / Workplace Education Civic Sport Culture
310,475 27,640 45,900 33,135 0 8,000 3,420
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Construction cost estimate
BU I L DI NG C ONSTRU C TI ON PROPOSAL TYPE OF U SE
FL O O R AR EA (M 2 )
UNIT CO S T (€/M 2 )
S UB TOTAL (€)
Residential Retail Office / Workplace Education Civic Sport Culture
565,345 96,350 261,730 92,135 7,875 22,750 26,220
3,000 1,500 2,000 2,000 2,000 985 3,150
1,696,035,000 144,525,000 523,460,000 184,270,000 15,750,000 22,408,750 82,593,000
Biodiverse roof area PV area
164,404 41,101
100 285
16,440,400 11,713,785
SU BTOTAL (€)
28 ,1 5 4,1 8 5
TOTAL (€ )
2 , 6 9 7, 19 5 , 9 3 5
LANDSC APE PROPOSAL TYPE
%
UNIT CO S T (€/M 2 )
S UB TOTAL (€)
85 100
5,192,325 14,253,442
69,000 3,381,000
85 100
5,865,000 338,100,000
(1,500 TR EES /HA) NO .
UNIT CO ST (€/TR EE)
S UB TOTAL (€)
310,500
100
31,050,000
AVE NU E
Hard landscaping Soft landscaping
203,621
40 60
SAVA RI VE RSC APE
Hard landscaping Soft landscaping TYPE
AR EA (M 2 )
61,686 142,534 3,45 0,000
2 98
Trees TOTAL (€ )
3 9 4 , 46 0 , 4 6 7
TRANSPORT & I NFRASTRU C TU RE PROPOSAL TYPE
Railway station Underground construction Demolitions & clearing of site TYPE
Tram
A R EA (M 2 )
UNIT CO S T (€/M 2 )
S UB TOTAL (€)
22,157 132,590 159,340
10,000 25,000 100
221,567,000 3,314,750,000 15,934,000
LENGTH (KM)
UNIT CO ST (€/KM)
S UB TOTAL (€)
22
14,060,000
310,726,000 550,000,000
Energy from Waste plant TOTAL (€ )
4, 4 12 , 9 77, 0 0 0
GR AN D TOTAL (€ )
7, 5 0 4 , 6 3 3 , 4 0 2
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This cost estimate is a basic calculation summary of all construction costs within the masterplan, based on the floor areas provided in the masterplan proposal. Cost rates have been based on, where possible, precedents of similar complexity in Croatia. The shown costs are net construction costs, not accounting for professional and statutory fees, VAT, and profit margins. Demolition and essential ground works (except in the case of the railway tunneling), as well as the pipework for the proposed central heating are excluded from the calculations. In the following design phase, costing would be revised by a quantity surveyor appointed.
Individual projects ŠE NOA OP E N DAN C E HO U S E R ECOR D , PRE SE RVE , DI SPL AY
The Open Dance House will bring back the memory of the forgotten rural past into the contemporary context, through folklore, play and craft. ZAG RE B P O L I T E K S T I L FACU LT Y OF TE X TI L E DE SI GN
An institution to drive the change to sustainable textile production with a mission to revitalise the Croatian textile industry. TH E BAL K AN FO R U M “A CHI L D OF JANU S”
Harnessing both the entrepreneurial spirit of migrants, and the aspirational growth of the local university, the Balkan Forum will provide an arena for the exchange of knowledge between refugees and students of the adjacent University of Zagreb, to stand as a beacon of cultural and educational prosperity. ZAG RE B E AT E RY R EF ECTORY AND C OOK E RY SC HOOL
A community-led project combating Zagreb’s food waste through social inclusion.
TH E SAVA E D U C AT I O N C E N T R E AWA R EN ESS THROU GH I NTE GRATI VE LE ARNING
M AS T E R PLAN
The Sava Education Centre aims to bring people back to the Sava by creating an emotional link that will strengthen a sense of identity within the city, and within the hearts and minds of current and future generations.
N
90
TUESDAY 1 8 O CTO B ER 201 9, ZAGR EB .
UNIVERSITY OF BATH S US TA I N A BL E C I T I E S
M.A R CH DESIGN S TUD IO 6 .1 201 9/20