Chavasse Park is 20,000m² green roof concealing a 3000 space underground car park in the centre of Liverpool. The park is the centre piece of the Paradise Street, Liverpool One regeneration project. The scheme has won a number of prestigious awards including a RICS award in the regeneration category and two BALI (British Association of Landscape Industries) awards for Willerby Landscapes, including the Grand Award 2008.
The terraced park provides wide areas of open amenity grass lawn together with a variety of ornamental planting beds. A large number of semi-mature trees were planted to create an instant established appearance to the park.
Tim O’Hare Associates was the project soil scientist working through Willerby Landscapes. The role initially involved working with the design team to develop a soil specification for the park. This covered the soil requirements for a range of topsoils and subsoil, together with appropriate sampling and testing protocols and soil management procedures. Such a demanding planting environment required high quality growing media which met the tight project specifications. In addition to meeting the horticultural requirements, the soils were also required to meet Liverpool City Council’s strict ground contamination targets.
During the construction phase, a soil testing and site monitoring programme was carried out to support the importation and placement of all the soils (9000m3) within the park.
The role included the following tasks:
- The preparation of a detailed Soil Specification as part of the landscape design.
- Sampling and testing (horticulture and contamination parameters) of the imported topsoil and subsoil rootzones at source.
- Interpretation of soil test data and the provision of sign-off reports for each soil type and source.
- Re-sampling and validation testing of imported topsoils to confirm compliance with the Site-Specific Assessment Criteria (contamination targets) agreed with Liverpool City Council.
- Inspection of soiling works (soil handling, subsoil and topsoil placement, decompaction measures, surface cultivations, fertiliser application, soil amelioration, tree and shrub planting, turfing, mulching) in all landscape areas.
- Recommendations for soil improvements and treatments where the correct soil quality had not been achieved.
- Preparation of a Completion Report for all soils used including supporting drawings, photographs and test results.
