Green Infrastructure - CLUVA

10 downloads 3658 Views 9MB Size Report
Providing space and opportunities for urban agriculture, a vital provisioning ... functionality; and create new green infrastructure components in areas of high ...
Green Infrastructure: An essential foundation for sustainable urban futures in Africa

Green Infrastructure: An essential foundation for sustainable urban futures in Africa The vegetation, water and open spaces within and around African cities provide many benefits for their inhabitants. Without this “green infrastructure” our cities would be hotter, more uncomfortable, more prone to flooding, produce less food, and be less attractive places to live, work, visit and invest. Yet across African cities we are witnessing a loss of this green resource – and of the associated benefits – through rapid development and inadequate planning. It is now time for planners and decision makers to plan effectively for this infrastructure, in recognition of the essential role it plays in the sustainable and climate conscious development of all urban areas. This information note can help with this process. It draws upon findings from a three year research project called CLUVA (CLimate change and Urban Vulnerability in Africa; www.cluva.eu), which has been conducted with universities and practitioners from across the African continent. It sets out: An introduction to green infrastructure An overview of the steps that were taken in CLUVA to inform green infrastructure planning (and which could be taken by practitioners in other African cities) Key findings for each of the five CLUVA case study cities.

Photos: (a) agriculture in a riverine valley, Addis Ababa (source: Sarah Lindley); (b) shade trees in Dar es Salaam (cover photo) (source: Gina Cavan); (c) people using waste leaves from wood processing to build the road to their houses, Douala (source: Rodrigue Feumba); (d) Bangr-weoogo urban park, Ouagadougou (source: Sarah Lindley); (e) street trees along the road by the river, Saint Louis (source: Adrien Coly); (f) trees in a public square, Saint Louis (source: Adrien Coly)

2

Who is this information note for and what does it provide? This information note is for planners and decision makers within all African cities. Whilst it focuses on research findings from five case study cities, the generic principles are relevant to many more. The document provides a set of steps to follow and key findings and recommendations for green infrastructure planning. It then provides a summary of the key findings from the application of this method in each of the case study cities in turn. The note is intended to help planners and decision makers to make informed decisions relating to the planning and management of green infrastructure for the many benefits it can bring. As such, it is not aimed solely at the environmental sector – green infrastructure has important consequences for the economic and social development of cities, and cuts across a wide range of agendas. It must be treated as a critical infrastructure, alongside the likes of energy, water, transport, and waste.

What is green infrastructure and which components are important? Green infrastructure is “an interconnected network of green space that conserves natural ecosystem values and functions and provides associated benefits to human populations”1. It includes all the green and blue components within and around the city – from parks and green spaces, woodlands and more natural habitats, to river corridors and lakes, street trees, incidental pockets of green, and the rural areas surrounding cities. It can include public and private gardens, vegetable patches, croplands, plantations, and open spaces. It exists as both planned and managed areas, as well as more natural, sporadic and informal components.

What benefits do we get from green infrastructure and how can it help us to adapt to climate change? Each component is important in a different way, and all of these components connect together to form a green infrastructure network which is important for the many economic, social and environmental benefits it brings. These benefits are increasingly referred to as “ecosystem services”2. They can be grouped into provisioning, regulating, cultural, and supporting services. As an example, provisioning services include food, water, timber, and fuel; regulating services affect climate, floods, disease, wastes, and water quality; cultural services provide recreational, aesthetic, and spiritual benefits; and supporting services include soil formation, photosynthesis, and nutrient cycling, which underpin the provision of the other services. In urban areas, where people and property is increasingly concentrated, the multiple benefits that we can get from green infrastructure are especially important in supporting sustainable development. This is especially true in the context of climate change, which will place increasing pressures upon cities and the provision of food – through heatwaves, drought and flooding. In particular, the regulating services that green infrastructure provide can help to adapt cities to some of these climate changes, for example by providing evaporative cooling, shading, and air corridors to help cope with increased temperatures; and by capturing and storing rain and flood waters and providing a permeable surface to allow them to infiltrate into the ground. Providing space and opportunities for urban agriculture, a vital provisioning service and urban ‘lifeline’, will also help to ensure on-going food supplies for inhabitants.

1

st

Benedict, M.A. and McMahon, E.T. (2002). Green infrastructure: smart conservation for the 21 century. Renewable Resources Journal, 20(3), 12-17. 2 Millennium Ecosystem Assessment (2005). Ecosystems and Human Well-Being: Synthesis. Island Press, Washington, DC .www.unep.org/maweb/en/index.aspx

3

Why plan green infrastructure? Green infrastructure planning allows decisions to be made to: safeguard important components of the green infrastructure network and crucial functionality; enhance key functionality; and create new green infrastructure components in areas of high need. A clear appreciation of the services from green infrastructure also means that, in situations where it is lost (for example, to new urban development), the functions and benefits that it provided are well understood and, as a result, appropriate compensation can be considered. With inadequate planning, the green infrastructure resource of African cities is being rapidly depleted and the benefits derived from it are being eroded. In addition, we miss the opportunity to maximise the benefits that we can get from the existing green infrastructure resource, which means that it performs poorly and does not meet the requirements of society. Green infrastructure is an important part of any planning effort, and can be closely associated with integrated water management planning at the city or local scale.

Photos: Some of the challenges presented by inadequate green infrastructure planning. (a) Informal settlements and problems of soil erosion, Addis Ababa (source: Sarah Lindley); (b) over-developed river corridors, Addis Ababa (source: Tekle Woldegerima / Mekonnene Biru)

Who needs to be involved? We all have a stake in the green infrastructure of our city; from experts and different departments in the city municipality, to landowners and local communities. It is therefore important to involve a broad range of stakeholders in the planning of this resource and in implementing plans.

Photos: (a) meeting of a CLUVA team with the local chiefs and community based organisation leaders of Mabanda, an unplanned settlement in Douala with 70,000 inhabitants (source: Rodrigue Feumba); (b) community engagement in Dar es Salaam (source: Manoj Roy)

4

Contents Section A: An overview of what has been done and how can it be applied........ 6 Step 1. Understand where and what green infrastructure there is ....................................................... 7 Step 2. Understand the benefits of green infrastructure and where they may be needed ................. 10 Step 3. Understand how green infrastructure has changed, may change in the future, and what this may mean in terms of the benefits derived from it ............................................................................. 14 Key findings and recommendations for green infrastructure planning ............................................... 17

Section B: Key city findings .............................................................................. 19 Addis Ababa, Ethiopa ....................................................................................... 20 Green infrastructure in Addis Ababa .................................................................................................... 21 Benefits of green infrastructure ........................................................................................................... 23 Understand how green infrastructure has changed, how may it change in the future, and what this may mean in terms of the benefits derived from it ............................................................................. 28 Planning green infrastructure in Addis Ababa ...................................................................................... 32 Who has been involved in this research in Addis Ababa? .................................................................... 34

Dar es Salaam, Tanzania .................................................................................. 35 Green infrastructure in Dar es Salaam.................................................................................................. 36 Benefits of green infrastructure ........................................................................................................... 38 Understand how green infrastructure has changed, how may it change in the future, and what this may mean in terms of the benefits derived from it ............................................................................. 45 Planning green infrastructure in Dar es Salaam ................................................................................... 49 Who has been involved in this research in Dar es Salaam?.................................................................. 51

Douala, Cameroon ........................................................................................... 52 Green infrastructure in Douala ............................................................................................................. 53 Benefits of green infrastructure ........................................................................................................... 56 Planning green infrastructure in Douala ............................................................................................... 58 Who has been involved in this research in Douala? ............................................................................. 60

Ouagadougou, Burkina Faso ............................................................................ 61 Green infrastructure in Ouagadougou.................................................................................................. 62 Benefits of green infrastructure ........................................................................................................... 64 Planning green infrastructure in Ouagadougou ................................................................................... 66 Who has been involved in this research in Ouagadougou?.................................................................. 67

Saint Louis, Senegal ......................................................................................... 68 Green infrastructure in Saint Louis ....................................................................................................... 69 Benefits of green infrastructure ........................................................................................................... 72 Planning green infrastructure in Saint Louis ......................................................................................... 75 Who has been involved in this research in Saint Louis? ....................................................................... 76

For more information ...................................................................................... 77

5

Section A: An overview of what has been done and how can it be applied Informing green infrastructure planning in your city Through CLUVA, steps have been taken in five African cities to inform green infrastructure planning. The cities the work has been undertaken for are Addis Ababa (Ethiopia), Dar es Salaam (Tanzania), Douala (Cameroon), Ouagadougou (Burkina Faso), and Saint Louis (Senegal). Each city faces a different set of challenges and represents a different climate zone and, as such, the methods and findings are broadly relevant for supporting green infrastructure planning in other African cities. This section summarises what was done and suggests a starting point for how you might apply the process in your city. It also links to the subsequent sections, which set out the key findings for each of the five cities in turn.

Step 1. Understand where and what green infrastructure there is 1.1 Characterise your city’s built and green structure using urban morphology types 1.2 Assess the land cover to get a more detailed understanding of the green infrastructure

Step 2. Understand the benefits of green infrastructure and where they may be needed 2.1 Familiarise yourself with the ecosystem services that green infrastructure can provide and good practice 2.2 Assess multiple functions and needs 2.3 Understand particular ecosystem services in more detail 2.4 Gain a deeper understanding from local communities

Step 3. Understand how green infrastructure has changed, may change in the future, and what this may mean in terms of the benefits derived from it 3.1 Assess past change due to development 3.2 Assess future change due to development 3.3 Assess climate change threats

Key findings and recommendations for green infrastructure planning - The CLUVA approach to inform green infrastructure planning - The process of green infrastructure planning - Priority themes for green infrastructure planning 6

Step 1. Understand where and what green infrastructure there is An early step to planning green infrastructure is to understand and map existing green and blue structures. They are not always in the obvious places, and often exist within even some of the most built up areas of the city. A characterisation of the city is one way to map this resource. In CLUVA, the cities were characterised according to their “Urban Morphology Types” (step 1.1) and a land cover assessment (step 1.2). 1.1 Characterise your city’s built and green structure using urban morphology types Urban morphology types (UMTs) are classes which link together the form of the land and its function. They are used to map discrete parcels of land. UMT maps are similar to land use maps, but the latter tend to only present the human use of the land and do not relate this to the form – or the features present, such as buildings, open spaces, trees and other vegetation. However, the form of the land can be very important in determining how it functions – this is especially true when we consider the way green infrastructure functions, and the benefits we can get from it, in different parcels of land. A UMT classification scheme was determined for each city, and then the individual UMT units (or parcels of land) were mapped from aerial photography and other datasets (Figure 1). Typically, parcels of land were mapped when they were larger than 1-2 hectares in size. Each parcel of land was assigned to one of the UMT classes. This process was then verified by site visits. The mapping was undertaken for an area which covered the city, as well as peri-urban areas. This is important for understanding the ecosystem services which are provided to the city by the surrounding rural areas. Figure 1: An example of the delineation and classification of urban morphology types from aerial photographs for Dar es Salaam

The UMT mapping helps to show where and what the main “patches” of green are within the city – these patches could be parks, forests, grasslands, etc. It also helps to show where and what the main green “corridors” are – for example river corridors and other linear green features. Further, it shows the extent of the city and the nature of the surrounding 7

countryside – whether it is largely agricultural land, plantations, or more natural habitats. What the UMT mapping does not show is where green inherently occurs within the more built-up parcels of land, sometimes referred to as the urban “matrix” – which could include smaller green components such as small parks, private gardens and open spaces within residential areas, or urban agricultural plots, street trees, etc. The green within the urban matrix can be considerable, and provides important ecosystem services, but often gets overlooked. A land cover assessment can help to determine where and what it is.

Photos: Examples of green urban morphology types in Dar es Salaam (source: Stephan Pauleit)

For key findings and examples of the UMT maps, refer to the cities that this was completed for: Addis Ababa – for 2011 and 2006 Dar es Salaam – for 2008 and 2002 Douala – for 2009 Ouagadougou – for 2009/10 Saint Louis – for 2011 Where to start? UMT classes can be developed for your city by using the most relevant classes from the cities above. You can decide which is most relevant by considering the climate zone of the city, the type of city, and the sorts of terms that you use within your governance structures. Develop your list with a range of local practitioners in different planning departments before coming to a final version. Once complete you will need to identify someone to map and verify the zones using recent aerial photography and field visits. When deciding on an area to map, remember to include the surrounding rural areas around the city which help to provide food, fuel, water and other resources for the city population.

8

1.2 Assess the land cover to get a more detailed understanding of the green infrastructure A land cover assessment helps to determine the land cover within each of the Urban Morphology Type (UMT) classes. Therefore you can determine how green or built-up each class is. This is important as it reveals the hidden green elements within the urban matrix. A land cover classification scheme was determined for each city (Figure 2). A set number of random points were distributed within each UMT category, and each point was compared to aerial photographs (for the same year as for the UMTs) to determine the land cover underneath it. This meant that average land cover characteristics could be determined for each of the UMT categories. Figure 2: An example of the land cover assessment from aerial photographs for Dar es Salaam

Specific land cover classes can vary but include: buildings, other built surfaces (such as asphalt roads and car parks), large trees, small trees and shrubs, crops, grass, and water. Other land cover classification methods can be used, such as remote sensing, if a full range of land cover types can be identified. For key findings and examples of the land cover assessment, refer to the cities that this was completed for: Addis Ababa – for 2011 and 2006 Dar es Salaam – for 2008 and 2002 Douala – for 2009 Ouagadougou – for selected UMTs for 2009/2010 Saint Louis – for 2011 Where to start? Land cover classes can be developed for your city by using the most relevant classes from the cities above. To develop your list, think about what you want to use the results for and what classes are possible to distinguish from aerial photographs. Once complete you will need to identify someone to interpret the classes from recent aerial photography.

9

Step 2. Understand the benefits of green infrastructure and where they may be needed Once you know where and what green infrastructure exists in the city, you can start to understand the benefits that are derived from it in a more systematic way. Within the CLUVA project this was done in a few different ways, through: a literature review of existing academic publications (step 2.1), a multi-functional assessment (step 2.2), more detailed analysis of particular ecosystem services (step 2.3), and exploring the issues with stakeholders and local communities (step 2.4). 2.1 Familiarise yourself with the ecosystem services that green infrastructure can provide and good practice An evidence base on ecosystem services was compiled, which holds examples of development / implementation projects as well research findings from reports and the academic literature3. In total it holds 86 international evidence studies, 42 of which have been summarised as case studies. It is not an exhaustive review of all published studies or implementation projects in this field. Evidence was categorised according to the climate zone it is relevant to, with a focus on those most relevant to the five cities. Although it must be stressed that evidence can be relevant across climate zones. Other material was included, particularly where examples illustrate additional themes, techniques or concepts not found for the African climate zones. The evidence was also categorised according to the ecosystem services that it refers to, including a mixture of provisioning, regulating, cultural, and supporting services. It includes examples that are quantified and a discussion of factors which affect or control the efficiency and effectiveness of ecosystem service delivery. In total, 24 ecosystem services are included in the database, with many of the studies evidencing multiple ecosystem services. The case studies can help you to find examples of good practice for your city and further afield – there will be more examples at a local level and these are worth identifying in order to support and encourage good practice and local initiatives through city level green infrastructure planning. For key findings, refer to the cities that this was completed for, but please bear in mind that evidence can be useful across climate zones: Addis Ababa – 7 studies for warm temperate climates with dry summers/warm winters Dar es Salaam – 19 studies for equatorial savannah with dry summers Douala – no particular studies identified for the equatorial monsoon climate, but studies for other equatorial climates (such as for Dar es Salaam above) may be relevant Ouagadougou – 12 studies for hot steppe / hot desert climates Saint Louis – 8 studies for hot desert climates Where to start? Find out what climate zone your city is in, and then look at the case studies completed and evidence base compiled for CLUVA Deliverable 2.6 to find those that are most relevant to your city. Read the abstracts and access more information using the links available. Please bear in mind that evidence can be useful across climate zones. The Millennium Ecosystem

3

CLUVA (2012). Deliverable 2.6: A database of international evidence of the ecosystem services of urban green structure in different climate zones. www.cluva.eu/deliverables/CLUVA_D2.6.pdf

10

Assessment4 and Manual for Cities from The Economics of Ecosystems and Biodiversity5 also provide useful starting points. Identifying good practice in your city and elsewhere is a good starting point, so that you are able to develop green infrastructure planning policies to support and encourage this. 2.2 Assess multiple functions and needs Green infrastructure within particular areas of the city may perform many different functions, and in addition many different functions may be required of them depending on a range of factors such as the demographics of local populations, proximity to features such as rivers and roads, or location on slopes or particular soil types. As such, it can be difficult for planners and decision makers to prioritise where green infrastructure is needed and what in particular is needed from it. A multi-functionality assessment, using the urban morphology types (UMTs) as its basis, provides a structured framework in which to start to assess the provision of and need for different ecosystem services. This can be used to help target policies and interventions, and to identify ecosystem services which require more detailed consideration and understanding. It can also help to scope out adaptation potential. In CLUVA, an indicative assessment was made for three of the cities using the judgement of local researchers and evidence. The multi-functionality assessment involves selecting a set of ecosystem services. For each ecosystem service, a judgement can be made by local practitioners or researchers as to whether each UMT in turn (a) already provides the ecosystem service and (b) needs to provide the ecosystem service. The judgements can be based on scientific and local evidence, local experience, and an understanding of the UMT – including its land cover. For key findings, refer to the cities that this was completed for: Addis Ababa – for 14 ecosystem services Dar es Salaam – for 12 ecosystem services Saint Louis – for 22 ecosystem services Where to start? Decide with stakeholders what ecosystem services are important for your city. Identify a suitable team to systematically review where the services are provided or need to be provided in each UMT, using the method set out in D2.8 and consulting with stakeholders and communities as appropriate. Identify a person to help to map the findings. 2.3 Understand particular ecosystem services in more detail In the context of CLUVA, particular provisioning and regulating ecosystem services were investigated and quantified at the city scale. The ecosystem services considered in greater detail were those relating to woody vegetation and local temperature regulation. The woody vegetation ecosystem services that were considered were the provision of timber and woodfuel, and the regulation of climate through carbon storage and sequestration. This

4

Millennium Ecosystem Assessment (2005). Ecosystems and Human Well-Being: Synthesis. Island Press, Washington, DC .www.unep.org/maweb/en/index.aspx 5 The Economics of Ecosystems and Biodiversity (2011). Manual for Cities: Ecosystem Services in Urban Management. www.teebweb.org

11

was based on an approach from the United Nations Food and Agriculture Organisation6, which was adapted to an urban context. It provides a fast way of quantifying urban woody resources based on the combination of the UMT mapping and land cover assessment. Local climate regulation services relating to surface and air temperatures were also considered. Surface temperatures were modelled using the freely available STAR tools7. This allows the impact of future climates and different urban development scenarios on surface temperatures to be assessed. Input parameters for the model were adapted to suit an African context. The UMT map and land cover assessment provided one input – an estimate of the proportion of ‘evapotranspiring’ surfaces (i.e. vegetation and water). Building mass is another input, and was adapted to represent values for typical buildings and roads within the cities considered8. Climate parameters are a further input. Simulations of surface temperatures were undertaken for 1981-2000 (baseline) and 2021-2050 (future) scenarios9. The focus for the modelling was a hot, cloud free day in the dry season and it is assumed that vegetation is evapotranspiring. The air temperature research shows how air temperature can be continuously monitored using low cost sensors distributed across the city. This can help to identify temperature differences in relation to a number of factors such as distance from the city centre, elevation, and surrounding land cover characteristics, including vegetation and water. For key findings, refer to the cities that this was completed for: Addis Ababa – for surface temperatures; further assessments of air temperatures and carbon sequestration and storage are ongoing Dar es Salaam – for surface and air temperatures, and services associated with woody vegetation including timber, woodfuel, and carbon storage and sequestration Where to start? Consider which ecosystem services it would be useful to have a more detailed understanding or quantification of in your city. If any of the ecosystem services presented in this information note are of interest then follow the methods set out in more detail in deliverable 2.8. It may be useful to link to a local university to assist with the research process. 2.4 Gain a deeper understanding from local communities Further work was undertaken at the local scale to: examine the ecosystem services provided to residents of low-income settlements, assess the impacts of climate change on the way people access and use these services, and identify innovative adaptation practices involving these services. In combination with the UMT and city level analyses, the findings start to formulate responses which help communities adapt to climate change and can inform green infrastructure planning, which should take into account the needs of all urban citizens. 6

Food and Agriculture Organisation (2011). Global forest resources assessment 2010 – Main report. Rome: UN FAO (FAO Forestry Paper No. 163). www.fao.org/docrep/013/i1757e/i1757e00.htm; Eggleston, S., Buendia, L., Miwa, K., Ngara, T. and Tanabe, K. (2006). IPCC guidelines for national greenhouse gas inventories, Vol. 4 Agriculture, Forestry and Other Land Use. Japan: Institute for Global Environmental Strategies. 7 The Mersey Forest and the University of Manchester (2011). STAR tools: surface temperature and runoff tools for assessing the potential of green infrastructure in adapting urban areas to climate change. www.ppgis.manchester.ac.uk/grabs 8 CLUVA (2013). Deliverable 2.8: A GIS based assessment of the urban green structure of selected case study areas and their ecosystem services. www.cluva.eu/deliverables/CLUVA_D2.8.pdf; see appendices P-R 9 Climate projections at 1km resolution were obtained from CLUVA simulations, performed for the period 19612050 for the A2 IPCC emissions scenario; CLUVA (2012). Deliverable 1.5: Regional climate change simulations available for the selected areas. www.cluva.eu/deliverables/CLUVA_D1.5.pdf. Climate data for Africa are freely available from the CLUVA project, see http://ict4eo.meraka.csir.co.za/cluva/ccViz.html.

12

Low-income urban communities may be more reliant on ecosystems for their livelihoods10, often lack access to green structures11, and are likely to feel the impacts of climate change more acutely and be less able to respond. At a global scale, the number of people living in such communities is increasing rapidly12. Whilst national governments tend to see poverty as mainly a rural issue13, it is anticipated that it will be an urban problem well before the 2050s14. For CLUVA, five criteria were used to select settlements for in depth case study analysis. These were: (i) flood-prone area, (ii) occurrence of flooding incidents, (iii) existence of local institutions, (iv) existence of adaptation practices, (v) undergoing development at booming or saturation levels. A variety of methods were used: participatory exercises, household and key informant interviews, case studies of critical incidents and institutions, visits to similar or contrasting settlements, and feedback sessions. This process identified green structures and ecosystem services of importance to local communities and a suite of climate adaptation responses that residents are involved in, both consciously and unconsciously. Such local information can help to identify good practice which should be supported and encouraged through city level green infrastructure planning. For key findings, refer to the cities that this was completed for: Dar es Salaam – two low income settlements of Suna and Bonde la Mpunga Where to start? Identify local communities to engage with, especially low-income settlements. For CLUVA, five criteria were used to select the settlements: (i) flood-prone area, (ii) occurrence of flooding incidents, (iii) existence of local institutions, (iv) existence of adaptation practices, (v) undergoing development at booming or saturation levels. Identify local researchers or individuals to conduct the visits and interviews. Ensure that good practice identified is fed into city level green infrastructure planning, so that it is supported and encouraged.

Photos: Understanding local community issues. (source: Rodrigue Feumba (left); Manoj Roy (right)).

10

Diaz, S. et al (2006). Biodiversity loss threatens human well-being. PLoS Biology, 4(8): 1300-1305. Bolund, P. and HunHammer, S. (1999). Ecosystem services in urban areas. Ecological Economics, 29: 293301; Mitlin, D. and Satterthwaite, D. (2013). Urban poverty in the global south: Scale and nature. London and New York: Routledge. 12 UN Habitat (2008). State of the world’s cities 2010/2011– cities for all: bridging the urban divide. Earthscan, London and Sterling, VA. 13 McKean, B. (2009). Invisible lives: stories of innovation and transition. Intersections, 10(2): 1-57. 14 Roy, M. et al (2013). Contrasting adaptation responses by squatters and low income tenants in Khulna, Bangladesh. Environment and Urbanization, 25(1). 11

13

Step 3. Understand how green infrastructure has changed, may change in the future, and what this may mean in terms of the benefits derived from it Green infrastructure in cities is under pressure from a number of sources – not least from urban development and climate change. This pressure can result in a loss of green infrastructure, and a reduced ability to provide the ecosystem services that are essential for city dwellers and the sustainable development of the city. In this step we look at past (step 3.1) and future (step 3.2) change due to development, as well as potential climate change threats (step 3.3). 3.1 Assess past change due to development Past changes in both UMT and land cover can be assessed when steps 1.1 and 1.2 have been undertaken for two different years. This allows a comparison to be made between the UMTs and land cover that were present previously with what is there now. It lets you identify the green UMTs which are under the greatest pressure to be transformed into settlements, and it allows you to see any loss of the vegetation land cover types within UMT categories. In both cities where the assessment of past change was undertaken, there is clear evidence of continued depletion of green structures and a rapid pace of change. This change will also result in a depletion of the ecosystem services provided by this green infrastructure. This is set against a backdrop of increasing urban populations, such that there is a higher need for ecosystem services within the cities at the same time as there is a reducing potential to provide these services. For key findings, refer to the cities that this was completed for: Addis Ababa – comparing 2011 and 2006 Dar es Salaam – comparing 2008 and 2002 Where to start? Undertake the UMT and land cover assessment for two different years, and compare the results between the two. 3.2 Assess future change due to development In CLUVA, the impact of potential development and urban growth on the UMTs was considered by modelling different spatial scenarios or patterns of development. Future development will have major impacts on green structures and the ecosystem services they provide. The modelling was undertaken for two cities for the time period up to 2025, divided into steps of five years. The cities were divided into grid cells (the size of which was determined by the size of the UMT units). Four scenarios were modelled to look at two main factors that can be influenced by planning: the population density (low or high density) and settlement location in high flood risk areas (allowed or prohibited). The model uses projected population growth15 and a set of ‘rules’, based on factors which represent the relative attractiveness of each cell for development. The factors include: past 15

United Nations Department of Economic and Social Affairs (2011). Urban agglomerations – City population. http://esa.un.org/unup/unup/index_panel2.html

14

land change dynamics, proximity to the city centre and sub-centres, proximity to the road network, proximity to existing settlements, location of known urban development projects, and steepness of slope. The cells that, according to the rules, are the most attractive for development are transformed into settlements at each time period. The rules applied are determined from an analysis of past development trends combined with expert and local knowledge. They are transparent and relatively easy to change so that the models can be used as interactive planning tools. The methodology is given in more detail in guidance documents16. For key findings, refer to the cities that this was completed for: Addis Ababa Dar es Salaam Where to start? The development of dedicated models can be a big undertaking. However, details about how the models were developed and applied are available through Deliverable 2.917 and the manuals provided to CLUVA stakeholders. This can help to make a judgement about whether and how to take this forward. Look at the key findings for each of the cities highlighted above and refer to the guidance documents mentioned. Look at past change in your city and discuss with local stakeholders potential future development patterns. 3.3 Assess climate change threats Despite a complex picture of possible positive and negative impacts of climate change on agriculture, it has been suggested that all African agriculture is at some risk from being negatively affected by climate change18. Over sub-Saharan Africa as a whole, rain-fed agriculture is particularly susceptible and agricultural GDP could fall by 2-9% under climate change scenarios19. Local situations and management practices vary, but there is often some local knowledge about how green structures are affected by climate and how much damage has been caused by past events, such as flooding or droughts. In CLUVA, local experts in one city were asked to give their initial opinions about how sensitive horticulture and field crops might be to heatwaves, droughts, floods and wind-storms of differing severities. When combined with information about expected future climate, this gives an idea about what adaptations may be needed and the additional resources which may be required. Adaptations which protect provisioning services are important because if agricultural and other staple products like fuel become scarcer, for whatever reason, then costs are likely to increase. Improving the resilience of farming systems for current climate variability will have benefits, even where additional impacts and opportunities are not fully known20.

16

Abo El Wafa, H. (2013). Urban settlement dynamics scenario modelling in Addis Ababa: Background Information and Technical User Guide; Buchta, K. (2013). Spatial Scenario Design Modelling in Dar es Salaam – Background information and Technical user guide. See www.cluva.eu/ Dissemination>Publications>Papers. 17 CLUVA (2013). Deliverable 2.9: Recommendations for green infrastructure planning in selected case study cities. www.cluva.eu/deliverables/CLUVA_D2.9.pdf 18 Müller, C. et al (2011). Climate change risks for African agriculture. Proceedings of the National Academy of Sciences of the United States of America, 108(11), 4313–4315. 19 Dethier, J-J. and Effenberger, A. (2012) Agriculture and development: A brief review of the literature. Economic Systems 36 175–205 20 Cooper, P.J,M. and Roe, R. (2011) Assessing and addressing climate-induced risk in sub-Saharan rainfed agriculture. Foreword to a special issue of Experimental Agriculture. Experimental Agriculture 47 (2) 179-184.

15

The work undertaken for CLUVA is a preliminary look at the issues, but is a starting point for local stakeholders to consider climate threats to green structures and to find ways to manage them. This need not be limited to crops. Where there is basic data on the tolerances of different species to climate, it can help to identify which indigenous species may be best suited to provide particular ecosystem services, as part of green infrastructure plans. For key findings, refer to the cities that this was completed for: Dar es Salaam Where to start? Discuss the issue of the sensitivity of green structures with a range of local stakeholders and experts. Use a set of past events as a reference and assess what sorts of damage to green structures occurred. Deliverable 2.8 includes a questionnaire that could be adapted if required21. It is also useful to identify the climate tolerance of different species within your city and use this to determine their suitability for different ecosystem services. Your findings can be related to other CLUVA outputs, e.g. climate change projections for Africa and African cities22.

Photos: Examples of urban agriculture in Dar es Salaam (Source: Sarah Lindley) 21

CLUVA (2013). Deliverable 2.8: A GIS based assessment of the urban green structure of selected case study areas and their ecosystem services. www.cluva.eu/deliverables/CLUVA_D2.8.pdf; see appendix L 22 See www.cluva.eu Dissemination>Publications and related sites http://ict4eo.meraka.csir.co.za/cluva/ftp1.html

16

Key findings and recommendations for green infrastructure planning The following summary presents some of the key messages from the green infrastructure work programme of the CLUVA project (outlined in steps 1-3 above). Further details are available in deliverables 2.6-2.9, all of which are available on the CLUVA website. The key findings and recommendations are grouped into priority themes for green infrastructure planning, the process of green infrastructure planning, and the CLUVA approach. Priority themes for green infrastructure planning 1. Green infrastructure planning should develop a comprehensive vision of the urban green structure based on sound evidence of its character, the ecosystem services it provides and its dynamics to develop locally adapted strategies for protection of existing assets and improvement where deficits exist. Areas prone to impacts from hazards such as flooding, landslides, storm surges, local flooding after rainstorms and where temperatures are elevated due to the heat island effect should be prioritised, especially where these hazards coincide with high population densities. It is suggested that the methodological approach developed and applied in this research is suitable for developing a comprehensive approach to green infrastructure planning. 2. Adopting a compact urban development strategy is a prerequisite for safeguarding the present and future green structure and its ecosystem services. However, densification still needs to ensure that there is an adequate supply of green areas and green cover so that the needs of the urban population can be properly met. This is particularly important for residential and community areas. 3. Maintaining green space within cities and increasing it where necessary is a priority. For example, this could include protecting productive areas near to where people live, reducing stormwater runoff, and moderating the negative impacts of the heat island effect on human health and well-being. 4. River corridors should be protected and rehabilitated where necessary as the multifunctional green backbones of the urban green structure. In the case study cities, they are increasingly built over by informal settlements, thus exposing more and more people to flooding and pollution. These trends need to be halted and reversed. 5. Moreover, protection of the remnants of natural areas such as the mangrove forests in coastal cities is vital for reducing risks from hazards such as storm surges but also for carbon sequestration and, not least, for the protection of biodiversity. 6. Urban agriculture and urban forestry are key priorities for securing survival of the fast growing population in African cities. Urban agriculture has a range of different forms, from growing vegetables in the backyard or keeping a few animals on small commons within informal settlements, to cooperative and commercial farming in peri-urban areas. All of these activities are highly important for the subsistence of the urban population, but they sometimes face great difficulties such as unsecure land tenure and lack of means for improving production. Similarly, urban forestry should be promoted (e.g. for producing timber, energy and environmental benefits). Large trees are a valuable resource for climate change adaptation. The process of green infrastructure planning 1. There is a need to develop strategies which link national, city and neighbourhood levels of decision-making as well as the relevant actors. The latter should include nongovernmental and community based organisations as well as municipal authorities. 2. Awareness needs to be raised about the importance of green infrastructure and ecosystem services, in order to link their protection with sustainable use and management. In many African cities, the importance of green spaces is underestimated in land use decisions. 17

3. Strategies need to link top-down approaches (e.g. for the development of sustainable urban development patterns across a city) with site specific approaches at the local level. 4. There is a lack of systematic planning for green infrastructure and a need to strengthen the capacity for planning and implementation. 5. A particular challenge will be to develop governance and strategic planning at the city regional level. In all case study cities, the municipal level seems far too limited to adequately address rural-urban interactions. It is crucial to consider economic, sociodemographic and ecological interactions between core cities and smaller towns and between urban and rural areas to successfully address the challenges of urbanisation and climate change. Adoption of Integrated Water Resources Management for entire catchment areas may be a suitable approach for this purpose and one through which strong connections to green infrastructure plans can also be fostered. The authority’s capacity and power for undertaking such an enterprise should be strongly improved. The CLUVA approach to inform green infrastructure planning 1. UMT datasets have been shown to be valuable as a spatial framework for characterising and mapping African cities. 2. UMT-based land cover assessments have helped to establish the essential properties of the different elements of the CLUVA case study cities. These in turn help to determine the ecosystem services associated with all elements of the urban fabric, and not just UMTs which are wholly or predominantly green. 3. Analysis of retrospective and prospective change has shown that green structures in African cities are already under severe pressure from development. Current development trajectories are likely to be unsustainable due to a serious loss of essential urban ecosystem services. Current controls to protect urban green structures seem to be having limited success. 4. A structured assessment of local knowledge has revealed differences in the possible sensitivity of some green structures to climate and climate-related events. 5. Surface temperature modelling for two cities suggests that development could be a much stronger driver of future urban temperatures than climate change. A low cost sensor network can illustrate the different air temperatures observed across UMTs and make connections with different land cover characteristics. 6. The multiple ecosystem services associated with woody vegetation have been quantified using transferable techniques. The loss of woody vegetation reduces beneficial temperature regulation, shading and carbon sequestration ecosystem services, and the impacts of some of these losses have been quantified. 7. Some parts of the CLUVA project assessed risks from stormwater runoff and riverine flooding but there is also a need to consider specific ways that green structures can help. 8. Local communities provide insights into problems, processes and possible solutions and comprise an important set of stakeholders. 9. Changes to urban ecosystem services are sometimes beyond the immediate control of local communities so there is a clear need for a range of stakeholders operating at different scales and with connection to a range of other sectors. 10. Examples of successful initiatives exist to help inspire ideas and identify good practices. 11. There is a need to understand the reasons for resistance to green structure goals plus how and why past schemes did not achieve desired effects. This may involve appreciating and accounting for possible ecosystem disservices. Where to start? Find out what is being done with regard to green infrastructure planning in your city and feed the above recommendations into the process. Consider how threats and any potential disservices might be best managed. You can use the evidence provided in this note and related CLUVA reports to make a case for following the steps outlined in this document for your city. 18

Section B: Key city findings For Addis Ababa, Dar es Salaam, Douala, Ouagadougou, and Saint Louis The next sections of this information note sets out selected key findings for the cities of Addis Ababa (Ethiopia), Dar es Salaam (Tanzania), Douala (Cameroon), Ouagadougou (Burkina Faso), and Saint Louis (Senegal). They can be used by planners and decision makers within each of these cities, but also provide an example for other African cities of what can be done.

Figure 3: The five CLUVA case study cities

Saint Louis Hot desert climate. Hazards include: sea level rise, flooding Ouagadougou Hot steppe / hot desert climate. Hazards include: flooding, heat, intense rainfall

Douala Equatorial monsoon climate. Hazards include: sea level rise, flooding, heatwaves

Addis Ababa Warm temperate climate. Hazards include, flooding, erosion, heat waves

Dar es Salaam Equatorial savannah climate. Hazards include: flooding, droughts, heatwaves, sea level rise

19

Addis Ababa, Ethiopa Key city findings Addis Ababa is the capital and largest city of Ethiopia. Its population of 2.9 million people in 2011 is set to increase to 4.7 million by 2025, corresponding with an average annual growth rate of 3.3%23. 80% of the city is comprised of slums. Addis Ababa is characterised by a warm temperate climate with dry winters and warm summers24. The city has a complex mix of highland climate zones. It has average annual temperatures of 16-18°C25, and its high elevation and position near the equator means that temperatures are fairly constant throughout the year. Climate change projections26 indicate no significant changes in the seasonality of rainfall, but slight changes in monthly rainfall and potentially significant increases in rainfall from March to May; seasonal temperatures are projected to increase by 1.5-2°C. The livelihood of the inhabitants is dependent on the periodical return of the rainy seasons; access to fresh water and fuel wood for cooking are also big issues27. Addis Ababa is affected by floods, droughts and heat waves28.

Photo: Westwards from the Churchill Road across a riverine corridor with crops towards Gola Mikael Church (dome within an area of mature trees) (source: Sarah Lindley) 23

United Nations Department of Economic and Social Affairs (2011). Urban agglomerations – City population. http://esa.un.org/unup/unup/index_panel2.html 24 Kottek, M. et al (2006). World Map of the Köppen-Geiger climate classification updated. Meteorologische Zeitschrift 15(3): 259-263. 25 CLUVA (2012). Deliverable 2.6: A database of international evidence of the ecosystem services of urban green structure in different climate zones. www.cluva.eu/deliverables/CLUVA_D2.6.pdf 26 For 2041-2050 relative to 1961-70; CLUVA (2012). Deliverable 1.5: Regional climate change simulations available for the selected areas. www.cluva.eu/deliverables/CLUVA_D1.5.pdf 27 www.cluva.eu/index.php?option=com_content&view=article&id=53&Itemid=61 28 CLUVA (2012). Deliverable 5.4: Preliminary Findings on Social Vulnerability Assessment in the Selected Cities. www.cluva.eu/deliverables/CLUVA_D5.4.pdf

20

Green infrastructure in Addis Ababa Urban morphology types A total of 12 high level urban morphology types (UMTs) and 36 detailed UMTs were mapped for 2011 and 2006, for an area covering a total of 520 km2 and encompassing the city of Addis Ababa as well as surrounding settlements and rural areas. The key findings presented in this section relate to the 2011 mapping (figure A.1). The residential UMTs are the main high level UMTs, covering 34.6% of Addis Ababa, followed by the agricultural UMTs (28.7%). Of the detailed UMT classes, field crops cover the largest area (28.1% of Addis Ababa), followed by the residential classes of mud / wood construction (16.0%) and villa and single storey stone / concrete (13.2%), then bare land (8.7%). The vegetation UMTs account for 11.8% of Addis Ababa. Plantation constitutes just over half of this category (51.4% of the vegetation UMT category), followed by mixed forest (30.9%), riverine vegetation (19.2%) and grassland (15.8%). The recreation UMTs account for only 1.9% of Addis Ababa. This category includes a mixture of detailed UMT classes, but notably the botanical garden to the north west accounts for almost three quarters of the land area associated with this category (72.7%), whilst parks account for only 6.9%. Figure A.1: High level (and some of the detailed) UMTs in Addis Ababa for 2011

21

Land cover 12 land cover classes were identified for Addis Ababa: built structure I (well planned and high rise buildings), built structure II (informal, generally unplanned, and non-high rise buildings), other impervious, other trees, eucalyptus trees, shrubs, grass, dark bare ground, light bare ground, field crop, vegetable crop, and water. Land cover was assessed for 2011 and 2006. The key findings presented in this section relate to the 2011 assessment. Almost half of the land cover of Addis Ababa as a whole can be grouped as ‘evapotranspiring’ (47%); this includes the land cover types of other trees, eucalyptus trees, shrubs, grass, field crop, vegetable crop, water (figures A.3 and A.4a)29,30. Bare ground accounts for 35% of the area; this is split into two categories of dark and light ground (figure A.2). Built surfaces account for 18% of the area; this includes buildings (split into built structure types I and II) as well as other impervious surfaces (figure A.3). Field crops, which is within the ‘evapotranspiring’ surfaces category, covers 21% of Addis Ababa. Field crops include tef (Eragrostis tef), the most important staple food in many parts of Ethiopia, and wheat. They are fed by rainfall once per year. Woody vegetation, which is within the ‘evapotranspiring’ surfaces category and includes other trees, eucalyptus trees, shrubs, covers 18% of Addis Ababa (figure A.4b). The distribution of these land cover types varies considerably between the UMT categories (figure A.2 and A.3). For example, within the residential UMT categories the proportion of ‘evapotranspiring’ surfaces ranges from 20% (for condominium and multistorey) to 26% (for mud / wood construction); whereas in the industry and businesses UMT, the range is from 7% (for storage and distribution) to 61% (for palace). Figure A.2: Proportions of evapotranspiring, built and bare ground surfaces across UMTs for Addis Ababa in 2011

29

Whether or not the vegetation actually evapotranspires depends to some extent on the species and whether or not it is irrigated. Plants can shut down their stomata and respiration processes when water stressed, such as at times with large vapour pressure deficits and low soil moisture, common in arid climates. 30 Percentages may differ slightly to those reported in CLUVA deliverables D2.8 and D2.9 due to rounding.

22

Figure A.3: (a) Evapotranspiring surfaces

31

and (b) tree cover in Addis Ababa for 2011

Benefits of green infrastructure Evidence of ecosystem services of green infrastructure and good practice Addis Ababa is in climate zone Cwb, a warm temperate climate with dry winters and warm summers. 7 pieces of evidence were gathered for this climate zone, 5 of which were written up as case studies. Further to this, the greatest amount of evidence gathered is for warm temperate climates (which incorporates a broad range of climates e.g. both temperate regions across Europe (Cfb) and tropical regions); with 47 pieces of evidence gathered and 15 written up as case studies (table A.1). A selection of this evidence is summarised below, although evidence from other climate zones will also be relevant. Remote sensing was used to confirm that highly urban areas are more prone to flooding due to lower storage and more runoff, and urban growth is a major contributor to an increase in runoff over time32. The proportion of built-up areas and soil type are important factors controlling runoff. In a UK context, simulations of adding green roofs significantly reduced surface run-off, by 1719.9% under 18 mm events33. Investigations of the thermal regulating functions of different tree species for human comfort found statistically significant differences between temperature, relative humidity and discomfort index in the locality of different tree species. Specifically, plants with a high level of evapotranspiration have the most thermally comfortable surroundings and the lowest human discomfort index34. Although this research is for the Mediterranean, the results may be applicable to the warm temperate climate of Addis Ababa, and could be useful in planning the location and species for human comfort.

31

Cavan, G. et al (2013). Urban morphological determinants of temperature regulation ecosystem services in two African cities. Submitted. The paper will be available from the CLUVA website once published. 32 Weng, Q. (2001) Modeling Urban Growth Effects on Surface Runoff with the Integration of Remote Sensing and GIS. Environmental Management 28(6): 737-748. 33 Gill, S.E. et al (2007). Adapting cities for climate change: the role of green infrastructure. Built Environment 33(1): 115-133. 34 Georgi, J.N. and Dimitriou, D. (2010). The contribution of urban green spaces to the improvement of environment in cities: Case study of Chania, Greece. Building and Environment 45(6): 1401-1404.

23

Local evidence provided for Addis Ababa (table A.1) presents green spaces that are currently being managed to enhance their quality and increase the benefits obtained from them. These case studies provide excellent evidence of how management can be successful. Urban agriculture in a medium-sized town in Kenya was shown to make an important contribution to income, nutrition and employment. The major reasons to practice urban farming were found to be the direct and indirect contributions to a household’s income. Comparison of urban farmers’ children with non-farmers’ children showed the positive effects on nutritional status, partially generated by the more diversified diet35. Table A.1: Details of case studies for warm temperate climates, including climate zone Cwb (Addis 36 Ababa), which provide evidence on ecosystem services of urban green structure Reference

Urban area

Ecosystem services

Lakes and Kim (2011). The urban environmental indicator "Biotope Area Ratio" - An enhanced approach to assess and manage the urban ecosystem services using high resolution remotesensing Weng (2001). Modeling Urban Growth Effects on Surface Runoff with the Integration of Remote Sensing and GIS Lindburg and Grimmond (2011). Nature of vegetation and building morphology characteristics across a city: Influence on shadow patterns and mean radiant temperatures in London Georgi and Dimitriou (2010). The contribution of urban green spaces to the improvement of environment in cities: Case study of Chania, Greece Tratalos et al (2007). Urban form, biodiversity potential and ecosystem services

Berlin, Germany and Seoul, Korea

Climate regulation

Climate zone Cfb; Dwa

Zhujing Delta, China

Water regulation

Cwa

London, England

Climate regulation

Cfb

Chania, Greece

Climate regulation

Csa

Various cities across UK

Cfb

McConnachie et a. (2008). The extent of public green space and alien plant species in 10 small towns of the Sub-Tropical Thicket Biome, South Africa Tiwari et a. (2006). An Effective Means of Biofiltration of Heavy Metal Contaminated Water Bodies Using Aquatic Weed Eichhornia crassipes D’Souza et al (2004). Does Ambient Temperature Affect Foodborne Disease? Takano et al (2002). Urban Residential Environments and Senior Citizens’ Longevity in Megacity Areas: The Importance of Walkable Green Spaces EPA. Addis Ababa River banks Rehabilitation Project

Eastern Cape, South Africa

Carbon sequestration; Climate regulation Aesthetic

Madhya Pradesh, India

Water regulation

Csa

Various cities across Australia Tokyo, Japan

Disease regulation

Csb/Csa/ Cfa/Cfb Cfa

Addis Ababa, Ethiopia Addis Ababa, Ethiopia Addis Ababa, Ethiopia Addis Ababa, Ethiopia Addis Ababa, Ethiopia Greater Manchester, UK Nakuru, Kenya

Aesthetic; recreational Aesthetic; spiritual; recreation; education Aesthetic; spiritual; recreation; education Aesthetic; spiritual; recreation; education Aesthetic; spiritual; recreation; education Climate regulation; Flood regulation Food

Cwb

SW Turkey

Wood and fibre

Csa

EPA. Upper catchment forest area rehabilitation project EPA. Medicinal plant garden project EPA. National Park Development and Indigenous Vegetation Reintroduction Project EPA. Development of the Gullele Botanic Garden Gill et al (2007). Adapting cities to climate change: The role of green infrastructure Foeken (2006). To Subsidise My Income – Urban Farming in an East-African Town - the benefits Ozdemir (2008). Estimating stem volume by tree crown area and tree shadow area 35

Aesthetic

Cfa

Cwb Cwb Cwb Cwb Cfb Cfb

Foeken, D. (2006). Chapter 6 – “The Benefits” pp. 79 – 94; in “To Subsidise My Income – Urban Farming in an East-African Town”; Leiden: Brill NV. 36 For references see CLUVA (2012). Deliverable 2.6: A database of international evidence of the ecosystem services of urban green structure in different climate zones. www.cluva.eu/deliverables/CLUVA_D2.6.pdf

24

Multiple functions and needs 14 ecosystem services were assessed: 6 provisioning services of food, wood and fibre, water (for irrigation), fuel, fresh water (primarily for drinking), and medicinal resources; 6 regulating services of local temperature control through shade, evaporative cooling, and the provision of cool air corridors, carbon sequestration and storage, and flood control from urban surface water and river sources; 1 cultural services of recreation; and 1 supporting service of habitats for species. Overall, the provision of the ecosystem services across the UMTs gets a lower score than the need for the services, with mean scores of 0.9 and 1.6 for provision and need, respectively (out of a total possible score of 3; figure A.4). This suggests that, in general, the green structures in Addis Ababa need to provide more services, or services to a greater level. The highest average scores are for the supporting, followed by regulating and cultural services, with the lowest scores for provisioning services. The cultural, followed by the regulating and supporting services, show the biggest gap between provision and need; the provisioning services show the least gap. This suggests that greatest attention should be paid to increasing regulating and supporting services, and in the UMTs that have the biggest gap. In general the north of the city and river corridors into the city provide the most services, whilst the need for the services tends to extend into the urban areas more. The UMTs providing the most ecosystem services are plantation, mixed forest, and parks; other UMTs with high scores are the botanic garden and religious sites. The UMT needing the most ecosystem services is plantation; other UMTs with high scores for need are mixed forest, riverine, botanic gardens, cemeteries and religious sites. A high number of needs are met in the north of the city, and in parks, the botanic garden, mixed forest, plantation, and grassland (figure A.5). This suggests that these UMTs, which are all green in nature, are generally good at performing what is needed of them. A high number of needs are not met in areas extending into the urban areas, in the residential UMTs, mineral workings, cemeteries, manufacturing, garage and river (figure A.5). This suggests that more is needed from the green structures in these UMTs. In terms of the provisioning services, the urban fringes have the highest provision scores; plantation, followed by grassland and botanic gardens. The score for the agricultural UMTs (field crops and vegetable farms) is relatively low, largely because whilst they provide food, their scores are lower for the other provisioning services assessed. Plantation scores highest in terms of need, followed by field crops and religious sites. In terms of the regulating services, the north of the city and river corridors have the highest provision, with mixed forest and botanic gardens scoring highest, followed by plantation and parks, and religion site. Plantation scores highest in terms of need, followed by mixed forest, parks, botanic garden, and cemeteries. The need clearly extends into the urban matrix. In terms of the cultural services, green patches within the urban matrix score highly for provision; parks score highest, followed by mixed forest, hotels, and villa and single storey. For need, this is predominantly highest within the urban area, where the population is. Eleven of the UMTs score highest; this includes riverine, parks, botanic garden, hotels, cemeteries, most of the residential UMTs, education and medical. It also includes energy distribution, which sounds unusual but was justified with the reason that “the land under electric transmission lines could not be used for construction; there is a very high need to use this vacant land for recreation”. In terms of the supporting services, mixed forest and religious sites score highest in terms of provision. They also score highly in terms of need, along with riverine, energy distribution, medical and river. Provision tends to be highest on the fringes, but need is fairly uniform across the city.

25

Figure A.4: Average scores for the provision of and need for all the ecosystem services assessed in Addis Ababa (the highest score possible was 3)

Figure A.5: Total number of ecosystem service needs that are met (i.e. there is a need for the service and the service is provided) or not met (i.e. there is a need for the service but the service is not provided) in Addis Ababa

More detail on particular ecosystem services Surface temperature modelling It should be stressed that the results reported here refer to average surface temperatures across the UMT categories, rather than air temperatures. The results suggest the existence of a considerable surface urban heat island in Addis Ababa. The difference is surface temperatures across the UMTs is around 28°C (figures A.6 and A.7). The range in surface temperature associated with land cover differences is much larger than that associated with different climate change projections, which is less than 1.5°C (figure A.7). It is generally the most built-up UMTs which experience the greatest increase in temperature with climate change. With respect to local temperature change, urban morphological change has the potential to have a much greater effect overall than temperature increase due to climate change. Increasing green structure cover in the urban matrix is likely to considerably offset local 26

temperature increases and also provide other benefits for urban residents, including shade, which is not considered in the modelling. Open markets and refuse disposal are the UMTs with the highest land surface temperatures (at 57°C and 54°C, respectively for 1981-2000), whilst vegetable farms have the lowest (29°C). Of the residential UMTs, condominium and multi-storey have the lowest proportion of green structures (20% ‘evapotranspiring’ surfaces) and the highest surface temperatures (43°C). Mixed residential has the lowest temperature (39°C) and the second highest proportion of ‘evapotranspiring’ surfaces (24%). Whilst mud / wood construction has the highest proportion of ‘evapotranspiring’ surfaces (26%) its temperature is the second highest (after condominiums and multi-storey) of all the residential UMTs (40°C). The quality of green structure is important in determining the effectiveness of temperature regulation services provision. Particular combinations of green structures, such as trees over grass, are more effective. They provide cooling through evapotranspiration and also shade. The model used does not consider the composition of green structure types. It is also recognised that there can be considerable variation of surface temperatures within UMT categories and that they are also affected by other local factors, which similarly affect the extent to which surface temperatures translate into air temperatures or physiologically equivalent temperatures (which are used for assessing human comfort). Figure A.6: Modelled maximum surface temperatures and evaporating fraction (green space and water) by UMT for Addis Ababa, for 1981-2000 and 2021-2050

27

Figure A.7: Modelled maximum surface temperatures 1981-2000 and changes from 1981-2000 to 2021-2050, for Addis Ababa

Understand how green infrastructure has changed, how may it change in the future, and what this may mean in terms of the benefits derived from it Past change The results in this section show key changes in the urban morphology types (UMTs) and land cover of Addis Ababa between 2006 and 2011. UMTs The most dramatic loss is of the agriculture UMTs (of 4,719 hectares or 9.1%); with field crops in particular suffering most of this loss (4,628 hectares or 8.9%). There was also a marked loss of the vegetation UMTs (of 1,440 hectares or 2.7%), although within this category mixed forest has actually increased slightly (figure A.8). The bare land UMT increased the most (by 1,813 hectares or 3.5%). This is followed by an increase in the residential UMTs (by 1,616 hectares or 3.2%); although within this category there are considerable losses of mud/wood construction and mixed residential, and increases in condominium and multi-storey and villa and single storey. There is very little change in the recreation UMTs, with slight increases for stadium and festival sites and parks. Land cover Overall an estimated 4,432 ha or 15% of the ‘evapotranspiring’ surfaces present in 2006 were lost by 2011. At the same time bare ground increased by 3,244 ha (an increase of 22%) and built surfaces increased by 1,190 ha (an increase of 14%). The increase in built surfaces was corroborated by a separate analysis of land cover change using remote sensing. This also showed a large increase in bare land. The most significant overall loss has been to field crops (by 2,011 ha, equivalent to 15%), followed by grasses (by 1,659 ha, equivalent to 33%), eucalyptus trees (by 806 ha, equivalent to 33%) and shrubs (by 388 ha, equivalent to 11%). There has been a slight increase in other trees (by 318 ha, equivalent to 7%) (figure A.9). 28

Figure A.8: Change from 2006 to 2011 in the area covered by each high level UMT in Addis Ababa 2000

1000

12. River

11. Bare land

10. Industry & business

9. Retail

8. Community service

7. Residential

6. Utilities & infrastructure

5. Transport

-3000

4. Recreation

-2000

3. Mineral workings & quarries

2. Vegetation

-1000

1. Agriculture

change (hectares)

0

-4000

-5000

High level UMT

Figure A.9: Overall change in land cover in Addis 2006 to 2011 4000

2000

1000

-2000

water

vegetable crop

field crop

light bare ground

dark bare ground

grass

shrubs

eucalyptus trees

other trees

other impervious cover

-1000

built structure type II

0

built structure type I

change in hectares (2006 to 2011)

3000

-3000

Whilst there has been an overall loss of ‘evapotranspiring’ surfaces (15% over the whole of Addis Ababa) there is much variation between UMT categories. The biggest losses of ‘evapotranspiring’ surfaces are in the stadium and festival UMT (29% evapotranspiring surfaces lost), followed by the grassland and medical UMTs (27% lost). The biggest gains in ‘evapotranspiring’ surfaces are in the mixed shopping and bare land UMTs, where there has been a 17% increase. The residential UMTs have all witnessed an overall loss of ‘evapotranspiring’ surfaces, mixed residential has seen the least loss of 1% whereas mud and wood construction has seen the greatest loss of 6% The remote sensing method demonstrates losses and gains in vegetation within the UMT classes across the city (figure A.10). Areas such as Bole in the east have lost much of their vegetation cover. 29

Figure A.10: Vegetation losses and gains in Addis Ababa between 2006 and 2011 by individual UMT unit (from remote sensing land cover change analysis)

Future change When compared to the low population density scenarios (scenarios 1 and 3), the high population density scenarios (scenarios 2 and 4) limit the expansion of Addis Ababa into its peripheral areas (figure A.11), reduce the settlement area that is located in high flood risk areas, and save large areas of agricultural land and other vegetated areas (figure A.12). Density also plays a role in the susceptibility of the population to floods. In the high population density scenarios (scenarios 2 and 4) there are far fewer new urban settlements in flood prone areas than in the low population density scenarios (scenarios 1 and 3). However, a higher population density in certain areas may mean that more people are susceptible to floods there. The prohibition of future settlement development in high flood risk areas while keeping the population density low (scenario 3) results in a higher loss of agricultural land and a lower loss of the other vegetated areas than for the low population density scenario where future settlement development in high flood risk areas is allowed (scenario 1). The prohibition of future settlement development in high flood risk areas along with a high population density (scenario 4) results in a slightly higher loss of agricultural land and lower loss of other vegetated areas than for the high population density scenario where future settlement development in high flood risk areas is allowed (scenario 2). The most attractive areas for settlement development in Addis Ababa based on the model are to the east and southeast (Bole sub-city), south eastern and southwest parts of the city (Niffassilk Lafto and Akaki Kality). The loss of riverine areas is lowest in the high population density scenario where future settlement development in high flood risk areas is prohibited (scenario 4) Scenario 4, with a high population density and prohibition of settlement in high flood risk areas, results in relatively low losses of agricultural land and other vegetated areas and no future settlement in high flood risk areas. This makes it the best of the four scenarios studied in this research.

30

Figure A.11: Settlement area in Addis Ababa from 2011-2025, for four different scenarios (where scenario 1 represents business as usual)

Figure A.12: Loss of agricultural land and other vegetated areas in Addis Ababa from 2011-2025, for four different scenarios (where scenario 1 represents business as usual)

31

Planning green infrastructure in Addis Ababa Key findings and recommendations for green infrastructure planning from the CLUVA project are summarised in section A of this information note, and are given in more detail in CLUVA deliverables 2.8 and 2.9. In this section we consider the case of green infrastructure planning in Addis Ababa. A new Master Plan is in preparation for Addis Ababa, of which green space planning is one of the components. Whilst it also formed part of the previous Master Plan, a number of issues had been identified including: a poor classification of green space components, land degradation and new development in the upper mountainous catchment leading to water runoff, low levels of publicly accessible green space, informal settlements and industries on river banks polluting the water, a loss of urban agricultural lands, and few street trees on pedestrian roads.

Photos: Some of the challenges for green infrastructure planning: (a) new development in the mountainous upper catchment leading to runoff, (b) informal settlements and industry on river banks polluting water (source: Kumelachew Yeshitela)

As such, the green space planning in the new Master Plan attempts to solve these problems, using the following guiding principles: Green space planning and development should be the basis not only for environmental protection, but also economic development All green spaces in the city should be ecologically networked The planning of green space should aim at ensuring multifunctionality. The new Master Plan uses a green space classification based on the urban morphology types. Specifically, five green proposals have been introduced that will be implemented at the structural plan level. The aims of each of these proposals and the associated ecosystem services are outlined below: 1. Multifunctional forest development on mountainous areas The development of forests on all mountains and land with a slope greater than 15% to provide fruits, honey, and wood for fuel and construction, carbon sequestration and storage, watershed management, habitat for wild animals and indigenous plants, and recreation. 2. River corridor rehabilitation Rehabilitation of the river banks of the city and cover with plants, to provide vegetables, fruits and honey, recreation, slope stabilization, flood mitigation and provision of water for

32

irrigation. Since the rivers pass through most areas of the city, planting the river corridors is expected to connect the various green spaces of the city. 3. Development and management of recreational parks The development and management of a hierarchy of parks for public recreation. Following the administrative structure of the city (i.e. city, sub-city, and woreda), four hierarchical levels have been identified for the management of recreational parks. These are: city park (>10 ha in size; to be managed at city level), sub-city park (1-10 ha; to be managed by sub-city administration), woreda park (0.3-1 ha; to be managed by woreda administration) and neighbourhood park (