Portuguese 
English 
Spanish 
7 min of reading 
0 comments 
Berlin approved a climate adaptation law requiring 440,000 recovered street trees by 2027, one tree every 15 meters, cool islands within 150 meters of any residence, and an investment of 3.2 to 4 billion euros over 15 years to reorganize streets and drainage against heatwaves.
Berlin has turned into law what began as a popular initiative on the streets of the German capital: the obligation to plant and recover trees on a scale that no European city had previously enshrined in legal text with defined goals, deadlines, and budget. The law, known as Berliner Klimaanpassungsgesetz (KAnGBln) or BäumePlus-Gesetz, approved by the Berlin parliament in November 2025 after pressure from the citizen initiative BaumEntscheid, establishes that the city must maintain 440,000 street trees in good condition by the end of 2027, distributed on average one tree every 15 meters on each side of the road or in the central median, and create accessible green spaces and cool islands with benches and shade within a 150-meter radius of any residence. The estimated investment for the complete program ranges between 3.2 and 4 billion euros over 15 years, according to estimates published by the German press after budgetary negotiations in parliament.
The law is not limited to planting trees: it creates a complete climate adaptation system that includes rainwater management, mapping of thermal stress zones, and measurable temperature reduction targets. The Berlin Senate announced in February 2026 its intention to create the Landesamt für Klimaanpassung (State Office for Climate Adaptation) with a staff increase that could reach almost 500 new positions, an institutional structure that reflects the scale of the challenge of transforming a city of 3.6 million inhabitants where asphalt predominates and heatwaves are no longer a rarity in Northern Europe. The legal text also requires the administration to identify and publish within a maximum period of one year the so-called “Hitzeviertel” (high thermal stress zones), neighborhoods where heat is most intense and where tree planting and green space creation measures should be prioritized.
What the law requires regarding trees on Berlin’s streets
The goal of one tree every 15 meters of street is the most visible point of the legislation and what generated the greatest public repercussion. The law establishes this average per road section, on each side or in the central median when there is sufficient space, and specifies that trees must be healthy or in good maintenance condition, a distinction that prevents the city from counting newly planted saplings as meeting the goal and mandates continuous investment in watering, pruning, and protecting existing trees. The intermediate goal for the end of 2027 is to reach 440,000 street trees, a number close to the goal Berlin already had for the end of 2025 (439,348), which means that the real challenge is not to plant hundreds of thousands of new trees, but to replace damaged ones and restore existing ones so that they achieve adequate shading conditions.
-
The rare city in the far north of Brazil that directly borders Europe, just by crossing a bridge
-
Copacabana Beach wakes up covered in waste after Shakira’s mega-show, and Comlurb removes an impressive 362 tons of trash in just a few hours in Rio.
-
Amsterdam declares war on meat, gasoline, and polluting travel ads on the streets and becomes the first capital in the world to cut advertising linked to high carbon emissions.
-
Abandoned Boeing 727 Becomes Dream Home in the Forest: Engineer Swaps Traditional Construction for Airplane Fuselage and Builds an Impressive Dwelling in Oregon
The law even creates a specific category for trees cultivated with innovative methods that accelerate growth. The text defines the “Entwicklungsbaum” (development tree), an specimen cultivated with techniques that allow it to reach, in about ten years, the expected cooling capacity of a healthy adult urban tree, recognizing that planting a sapling today does not solve tomorrow’s heat problem and that the city needs solutions that accelerate the creation of shade on streets where asphalt accumulates temperatures that can exceed 50 degrees Celsius on the hottest days. The pace of tree replacement and restoration requires logistical planning involving urban nurseries, maintenance teams, and a planting calendar that respects the seasons, an operation that the future State Office for Climate Adaptation will have to coordinate with the city’s 12 administrative districts.
How the cool islands that the law obliges Berlin to create work
The requirement that every Berlin resident has access to an island of freshness within a 150-meter radius of their home translates into meters what the law understands as a basic right to protection against extreme heat. According to the legal text, an island of freshness (Kühlinsel) is a public space of up to 0.3 hectares with at least 30 square meters of area, mostly without impermeable paving, with abundant vegetation, sufficient shade, and benches to sit on, literally a place to rest when the heat becomes dangerous for the elderly, children, and people with health problems. Andreas Kraus, a representative of the Berlin government, summarized the logic at a press conference: thermal stress frequently coincides with social pressure, an observation that points to the fact that poorer neighborhoods in Berlin usually have fewer trees and more asphalted surfaces, an inequality that the law seeks to correct by prioritizing investments in Hitzeviertel.
In addition to the islands of freshness, the law requires that every Berliner can walk to a green space of more than one hectare within a 500-meter radius of their residence. The thermal goal is specific and measurable: in Hitzeviertel, blue (water) and green (vegetation) infrastructure measures must reduce maximum daytime temperatures in public spaces during heatwaves by at least 2 degrees Celsius compared to a scenario without these interventions, an objective that transforms tree planting from a symbolic action into urban engineering with verifiable results by thermometers. The distribution of trees, islands of freshness, and green spaces throughout the city requires detailed mapping to identify gaps where residents live too far from green areas, a task that the law obliges the administration to complete and publish in the first year of its validity.
Why Berlin wants to transform into a sponge city in addition to planting trees
Rainwater management is the second front of the law that complements tree planting and addresses a problem opposite to heat: floods. Berlin wants to become a “Schwammstadt” (sponge city), a concept where rainwater falling on impermeable surfaces is retained, infiltrated, and used on-site instead of being discharged into the combined sewer system that mixes stormwater with domestic sewage and which, during intense rain events, overflows and pollutes the city’s rivers and lakes. The law stipulates that, in areas with a combined sewer system, at least half of the impermeable surfaces should be disconnected from the network whenever feasible, directing rainwater to the soil, to retention reservoirs, or for irrigating the very trees that the law mandates to plant.
Investment in sponge city infrastructure had already begun before the law was approved. In 2025, the coalition governing Berlin allocated 300 million euros specifically for investments in water infrastructure aimed at the Schwammstadt concept, a value that is part of the package linked to the implementation of BäumePlus and will finance sustainable drainage works, rain gardens, permeable pavements, and retention systems that transform streets and squares into surfaces that absorb water instead of expelling it into the sewer. The logic of the sponge city serves two simultaneous objectives that the law recognizes as inseparable: preventing floods during intense rain events and ensuring water reserves to irrigate trees and green spaces during drought periods that climate change makes increasingly frequent in Berlin summers.
How much does the transformation cost and who will carry out the work
The debate about the cost of Berlin’s climate adaptation has accompanied the project since the popular initiative BaumEntscheid brought the proposal to parliament. The regional government initially rejected the popular referendum proposal, claiming costs of at least 7.2 billion euros for the period from 2025 to 2040, a value that, after negotiations and legislative adjustments, was reduced to an estimate of 3.2 to 4 billion euros over 15 years for the program approved by parliament, a difference that reflects both cuts in the original scope and different cost calculation methodologies. Regardless of the final number, the investment is in the order of billions and will be distributed among tree planting and maintenance, construction of freshness islands, urban drainage works, de-sealing of surfaces, and hiring of personnel for the new State Office for Climate Adaptation.
The practical question of who will do the work is as relevant as the money. The Berlin Senate announced the creation of the Landesamt für Klimaanpassung with a reinforcement of nearly 500 staff positions to coordinate the implementation of the law, a structure that will need to articulate actions among the city’s 12 administrative districts, tree nurseries, construction companies, water and sewage utilities, and urban maintenance teams. The Berlin experience offers a lesson for other cities facing increasing heatwaves: planting trees without a budget, staff, and scheduled maintenance for years does not produce measurable results, and the difference between a campaign promise and real climate adaptation lies precisely in the deadlines, meters, and euros that Berlin’s law puts on paper.
And you, do you think Brazilian cities should adopt a law similar to Berlin’s to combat heatwaves? Leave your opinion in the comments.
Be the first to react!