Desealing: Potential, Impact and Funding

In short. Desealing reopens sealed surfaces, asphalt, concrete, paving, for infiltration, evaporation and greening. The benefit is twofold: during heavy rain, water infiltrates on site instead of burdening the sewer; during heat, evaporation cools and greenery provides shade. Desealing measures are fundable through the DAS funding guideline of the BMUKN and the federal programme "Adaptation of Urban and Rural Areas" (BMWSB/BBSR), as well as through state programmes and urban development funding (last reviewed: August 2026).

Why this matters for your municipality. Germany continues to seal land every day, the Federal Environment Agency (Umweltbundesamt, UBA) reports figures in the double-digit hectare range per day. Every sealed surface worsens runoff and heating. Desealing reverses this, particularly where surfaces have lost their function: abandoned car parks, overly wide traffic areas, unused yards. For you, this is a lever that connects heavy rain and heat prevention and can be financed with funding.

What measurable benefit does desealing bring?

The effect depends on area and subsoil but is documented in both directions. On the water side: a desealed, infiltration-capable surface absorbs a significant portion of the rain on site instead of feeding it into the sewer, reducing peak runoff during heavy rain. On the heat side: sealed surfaces heat up strongly and release the heat at night; desealed, greened surfaces stay noticeably cooler and cool through evaporation. Desealing is thus a core component of the sponge city principle.

Which surfaces are suitable for desealing?

The easiest surfaces are those with no current use: derelict car parks, oversized turning areas, abandoned depot yards, wide verges. School yards and neighbourhood squares also offer potential when use and desealing are considered together. To find the right surfaces, a systematic potential analysis helps: bringing together the degree of sealing, subsoil, distance to groundwater and demands on use. This links up with the exposure analysis, which shows where relief is most urgently needed.

What funding is available in 2026?

The most important federal route for municipalities is the DAS funding guideline of the BMUKN, focused on municipal adaptation management and pilot projects; higher funding rates are possible for financially weak municipalities. In addition, the federal programme "Adaptation of Urban and Rural Areas" funds investment projects. The standalone DAS funding guideline has been closed to new applications since August 2025; further calls have been announced without a fixed timetable. For the federal programme "Adaptation of Urban and Rural Areas to Climate Change" (BMWSB/BBSR), the fifth tranche recently ran with around 80 million euros in federal funds; the deadline for project outlines ended on 3 July 2026. 326 outlines were submitted with an investment volume of 928 million euros, demand clearly exceeds the available funds. State programmes are available in addition (last reviewed: August 2026).

The honest limit. Desealing only works where the subsoil allows infiltration. On compacted, contaminated or deeply built-up soils, the effort is high and the effect limited, in some cases soil replacement is required. Contaminated legacy sites can sharply increase costs. And desealing competes with other demands on land: a car park that is desealed is no longer available as parking space. Without clarifying the question of use, the project fails in political discussion, not on technical grounds.

When KomAdapt is worthwhile. The art lies in filtering out the most effective surfaces from many possible options and finding the right funding route. KomAdapt links exposure analysis (where does heat and heavy rain create the most pressure?) with measure prioritisation and a funding roadmap that reflects the current programmes. This is worthwhile if you want to approach desealing strategically and justify applications cleanly.

_What exactly does desealing mean?_ Returning a sealed surface to a water-permeable, often greened state. The surface covering is removed, the subsoil loosened or replaced, and the area redesigned. Partial desealing with permeable surfacing is a graduated variant. _How much land is sealed every day?_ The UBA reports the figure for new land take; it averaged 50 hectares per day over the years 2021 to 2024. The federal government's target is fewer than 30 hectares per day by 2030. The political goal is reduction (last reviewed: August 2026). _What funding is available in 2026?_ Central is the DAS funding guideline of the BMUKN (project sponsor ZUG), currently without an open application window, as well as the federal programme "Adaptation of Urban and Rural Areas" run by BMWSB and BBSR. In addition, state programmes and urban development funding (last reviewed: August 2026). The Municipal Guideline (Kommunalrichtlinie) funds climate mitigation only. _Is desealing worthwhile economically?_ On its own, it is an investment with no direct return; the value arises indirectly: avoided heavy rain damage, reduced sewer load, lower heat impacts. With funding and the dual effect, the overall balance improves. _Who decides on desealing?_ A cross-cutting task between civil engineering, urban planning, and the environment and green spaces department. For municipally owned land, the decision usually lies with the municipality itself. Early clarification of demands on use is the most important success factor.

Inbound links should be set from: heavy-rain-urban-water, sponge-city-principle, climate-adaptation-funding.