Synthesis; heat proof The Hague + dŚĞ,ĂŐƵĞϮϬϰϬ DƵŶŝĐŝƉĂůŝŶŝƟĂƚĞĚĂĐƟŽŶƐ Klaas Akkerman Heat networks; Expansion of heat network adding green structure in renewed streets Green structure; Renewal and restructuring of neighborhoods Development focus zones 6. ZĞŶŽǀĂƟŽŶ Accessible water; “Swimming Singels” Scheveningen/ Kijkduin 'ƌĞĞŶǁŝƚŚĨƵŶĐƟŽŶƐ͖ Haagse Markt A 1. ŽŵŵƵŶŝĐĂƟŽŶ͖ Heatplan 3. 7. 2.A 4. Scientific Master Thesis 5. WĂƌƟĐŝƉĂƚŽƌŝĂůĂĐƟŽŶƐ 1. Wastelands 2. ‘Haagse tuintjes’ Green roofs and façades Green industrial areas džŝƐƟŶŐƐƚƌƵĐƚƵƌĞ Forest and parks Vliet and Singles 0 0,5 1 2,5 5 km 2 ~ INTEGRATING FOR COOLER CITIES ~ 3 The Hague 2040+ AN INTEGRATED APPROACH TOWARDS HEAT PROOF CITIES Msc. thesis Delft University of Technology © 2015 Klaas Sijmen Akkerman Published as a graduation research thesis at the Faculty of Architecture and the Build Environment under the chair of Urban Metabolism at the Technical University of Delft, The Netherlands. All rights remain with the author. Cover image by Frans Snijder, edited by author. Template by Luuk Graamans, adapted by author. 4 The Hague 2040+ AN INTEGRATED APPROACH TOWARDS HEAT PROOF CITIES Master of Science (MSc) thesis The Hague 2040+ - An integrative approach towards heat proof cities. 03-07-2015 Author Klaas Sijmen Akkerman Student number 1502182 Mentors Dipl.ing. Alexander Wandl, Msc. Urbanism ̶ Researcher Environmental Technology & Design Dr.ir. Frank van der Hoeven Urbanism ̶ Associate Professor Urban Design External committee member Ir. Ype Cuperus AE+T ̶ Associate Professor Architectural Engineering Delft University of Technology, Faculty of Architecture and the Built Environment, Department of Urbanism. 5 6 Executive Summary Globally we are facing a changing climate resulting in more extreme weather; more heatwaves, extreme drought, and heavy rainfall will be common events during the 21st century. Data collected by National Oceanic and Atmospheric Administration (NOAA) and the Japanese Meteorological Agency, published by Bloomberg revealed that 2014 was the warmest year ever on record. Temperatures during the first half of 2015 have already beaten last year’s records (Bloomberg, 2015). Increasing temperatures, especially during hot summers have a huge impact on our cities; since urban heat islands will be formed. This means that cities accumulate heat and consequently are warmer than their rural surroundings (Salcedo Rahola, Van Oppen, & Mulder, 2009a). This causes heat stress which has negative effects on human health and an increased demand for resources (Kleerekoper, 2009; Van der Hoeven & Wandl, 2013). In order to adapt to these changes, cities all around the world are developing climate adaptation strategies. In this context The Hague has responded reluctantly. This is alarming since research on surface heat islands in Dutch cities by TNO has revealed that temperatures in The Hague are on average 8,6˚C higher than outside the city, making The Hague the warmest city in The Netherland (Hove et al., 2011). A climate assessment carried out in this research on The Hague reveals that especially the dense city core and Scheveningen are extremely vulnerable for urban heat. The vulnerability is mainly determined by the lack of green structure, high population densities, and low rated liveability. At the moment vulnerable groups, in this case elderly people, still live outside the vulnerable areas. However, demographic predictions show that the number of elderly in the warmer areas will rapidly increase until 2040 (Starmans & Vermeulen, 2012). Several (international) research institutes and programs agree that in order to execute an effective climate plan, an integrated approach is needed (“Climate Proof Cities,” 2015; IPCC, 2009). This implies that consideration has to be paid to opportunities already present and whether adaptation- or mitigation measures can be integrated in existing development strategies. 7 In order to develop an integrated climate adaptation strategy an assessment on The Hague’s spatial planning-policies is performed. From this it can be concluded that The Hague does not possess any plans regarding urban heat mitigation in her spatial planning or climate plans. Even more so, current plans to increase built density in the city core will even increase heat problems. Actions to improve the city’s green structure are planned in areas where they have no contribution to the mitigation of heat stress. Nevertheless these and other planned actions and relating policies do offer possibilities for heat mitigation, albeit that locations or execution have to be changed. Integration of climate adaptation strategies in other policies is already done in other cities. A study of Singapore shows that implementation and maintenance of extensive green structures not only increases liveability of the city, but can also be used to attract foreign investment. Stuttgart has a long tradition with environmentally aware development. The green structure surrounding the city is used to ensure inflow of cool and fresh air into the city. In order to optimize airflow, guidelines for buildings and regulations for open areas have been recorded in the city’s climate atlas. Three design studies have been executed to develop a strategy for heat mitigation in The Hague. The first study, Green The Hague, shows the development of a green structure in both public and private areas. Narrow streets in the city core often leave no room for planting of trees, but private inner courts do. Green roofs also play part in this study, as they can be installed on the flat roofs in the warmer parts of the city. In all studies collaboration between the municipality, home owners and individuals is crucial. This is already enforced by the city’s Structure Vision. Dense The Hague, the second study, shows that further intensification of land use, as planned by the municipality in the city core, is unwanted. Since the municipality prefers to develop close to the city centre, the International Zone and Haagse Hout have been appointed as development areas. The extension of the city-heating networks, as proposed by the Housing Vision, offers opportunity to re-arrange (underground) infrastructure and restructure public space. Creating room for the development of green structure must be made. 8 Executive Summary Finally, Healthy Ageing in The Hague shows demographic trends towards the ageing of The Hague’s population. Currently the elderly live outside the warmer parts of the city, with the exception of Scheveningen. By 2040 over 20% of the population living in the warmer areas will be over 65, putting the elderly at risk. National policy prescribes that people have to be able to live as long as possible in their own houses. To enable this, houses need to be adapted. These adaptations can be combined with renovation and the execution of the measures for mitigation as proposed in the other studies. The synthesis of these three studies has resulted in a set of key actions The Hague can adopt to execute her ambitions to effectively mitigate urban heat. The key projects are: ◊ City-heating networks; installation of city-heating should be combined with restructuring of (underground) infrastructure to allow more room for green structure in streets. ◊ Urban renewal; creates opportunity to restructure public space to make room for ‘refuge zones’ and green structure. ◊ Accessible water; inner city water can be made accessible to reduce heat stress on hot days. This can be combined with the increase of water retention areas. ◊ Green with functions; combining the development of a new green structure with functions can create feasible business cases. ◊ Heat plan; communication and education are the cheapest and most effective ways to prepare people for periods of sustaining heat. 9 10 Preface This thesis focusses on exploring ways to integrate climate adaptation measures related to urban heat in municipal spatial planning. The thesis is the final part of my graduation project. In this graduation project I continue the work done by Bart van den Heuvel and Laura Kleerekoper in their theses The Hague’s Options Against (2009) Urban heat and Design Principles For Urban Heat (2009). In 2014 I conducted a research on healthy living environments, De Gezonde Stad (Akkerman, 2014) during an internship at engineering company Witteveen+Bos in The Hague. Starting point for that research was the fact that currently over 50% of the world population lives in cities. This number is expected to increase to over 75% in the next 40 years (United Nations, 2012). This development will have major impact on the way we use land and resources. The question was: how do we keep our living environment healthy; how to keep out cities and homes liveable, connected and safe? The conclusion of that research was that these questions can only be answered by approaching them in an integrated way. Witteveen+Bos and Ad de Bont, urban de- signer at the Technical University Eindhoven in 2013 came to the same conclusion: “A healthy city offers an attractive, liveable and safe living environ- ment for its residents. A healthy city is a city that seduces to a healthy lifestyle. A city in which plenty of walking and cycling takes place. A city in which there is enough room the move and play around and which offers meaningful parks and public spaces. Healthy Design is often biased towards a specific focus, such as cycling, green, sports or an environmental view. An integrated approach is required (internal memorandum (Akkerman, 2014).” Urban heat was a returning