Nature-based solutions in Wroclaw: Renovated courtyards and green streets

A treelined renovated courtyard in Wroclow with trees, paths and benches.

Area characterisation:

The city of Wroclaw has over 642,700 inhabitants. It is the fourth most populous city in Poland and the administrative capital of the Lower Silesia Province. Wroclaw is a heart of a wider agglomeration of more than 1m inhabitants. Located on the Oder River, up to 36% of the city is at risk of flooding despite extensive flood protection works. The city also experiences increasingly common heat waves and drought during summer, exacerbated by the urban heat island effect. The demonstration projects were implemented in the Olbin district of the city, a dense urban area of approximately 0.8 km2 that ranges from wealthy to socially deprived. The area is a local urban heat island, exposed to heat waves and frequent rainfall.

Objective:

To demonstrate the potential for nature-based solutions to reduce heat stress and flooding and provide other co-benefits
To engage citizens in designing nature-based solutions that meet their needs.
To develop an effective strategy for nature-based solutions to contribute to climate change adaptation across the city.

Start/end date:

1 January 2017 - 1 January 2020

Images

Financing:

The demonstrators were implemented under the European Project GROWGREEN – Green Cities for Climate and Water Resilience, Sustainable Economic Growth, Healthy Citizens and Environments. This project has received funding from the European Commission’s Horizon 2020 research and innovation programme.

Further, a resolution of the Council on property tax reduction and ecology seeks to encourage and promote the creation of green roofs and walls through tax exemptions or reductions.

Potential impacts/benefits:

Reduced heat stress and flooding in the neighbourhood of the demonstration project.
An improved environment for local people, providing pleasant spaces to meet and play, as well as benefits for biodiversity.
For the enhancement of biodiversity, more than 100 species of shrubs and herbaceous plants were added in the project location.
Increased awareness and understanding of nature-based solutions among the local population.
A strategic basis for further development of nature-based solutions across the city.

Actions:

The Wroclaw demonstrators, implemented under the H2020 GrowGreen project, included seven renovated courtyards bounded by a green street. The renovations are a combination of green walls, pocket parks and other interventions (green parklets, thematic gardens, etc.), located within 200 m of one of the area’s main streets. The locations were determined by the residents needs as a result of their participation along with inputs on local climate parameters, air circulation, spatial constrains and ownership.

Actions for Improvement of Climate, Air Quality and Biodiversity

• reduction of the number of treatments in green areas,

• mulching and mycorrhization,

• loosening of soil structure and soil replacement,

In several areas, ruderal plants were allowed to partially grow into the edges of the beds, and in one location they were allowed to colonise space in paved areas. Creating a food base and habitat for birds and insects was part of the project. Special attention was paid to melliferous (pollinators for bees) plants, which were introduced in larger groups and at the edges of yards. Elements such as insect houses and birdhouses were built along with natural features (trunks of native tree species) left as habitats.
Water management

Systems were put in place for capturing and collecting rainwater and snowmelt. These include collecting rainwater into rain barrels for watering plants and collection in raingardens, swales and infiltration into the ground.

The introduction of native vegetation resistant to dry conditions was included along with planting in the lowest parts of the area where rainwater accumulates. A community garden maintained by residents was also included.
Recycling materials

Attention was given to the reuse of items from demolition. Following options for the use of recycled materials were identified:

• aggregate and crushed concrete from edging - addition of pedestrian pathway and waste shelter substructure provided the required substructure parameters are maintained.

• segregated sand from troughing - addition to the road base and used for grading of terrain;

• granite slabs from demolitions - roadsides, finishing of lowered flowerbeds, pedestrian routes in greenery, development of community gardens.

• granite slabs from demolition of sidewalks - roadsides, green walkways, development of community gardens;

• demolition bricks - finishing of waste shelters;

• wood from cuttings - separating playgrounds and zones in green areas, edging flowerbeds;

• biomass, compost - addition to fertile soil;

• water barrels – reusing tanks

Transferability of result:

The demonstrators contribute to the evidence base of NbS in cities. Wroclaw has collaborated with a number of replication cities in Poland, with the objective of providing lessons learnt and replicable means for increasing urban climate and water resilience, social, environmental and economic benefits through NbS implementation and strategy development.

The outcomes of the demonstration projects fed into to the development of a strategy for NbS, as part of Wroclaw’s climate change adaptation plan.

Lessons learnt:

- The project is influencing strategic thinking on green infrastructure and acting as a catalyst for the development of other NbS projects in the city;

- Engaging citizens from the design stage is key to ensure their understanding, acceptance, and support for future maintenance;

- Engaging with local stakeholder and ensure specialist skills are critical aspects;

- Challenges in public procurement are often encountered when dealing with NbS in public tenders.