Measuring landscape performance for a subdivision in Canterbury, New Zealand: Reflections and critique of methods

Abstract

Completed in 2019, Te Whāriki (Phase 1& 2) is a 144-acre residential subdivision adjacent to Lincoln University in Canterbury, New Zealand. The project transformed a dairy farm into a high-performance residential landscape featuring a series of constructed wetlands. According to its design goals, Te Whāriki is expected to help support local biodiversity, improve downstream water quality, reduce car dependence, encourage the use of alternative transport, and provide opportunities for food collection and harvesting. With support provided by the Landscape Architecture Foundation (LAF) and the design firm - Earthwork Landscape Architects, we measured the actual performance of Te Whāriki, as a part of the 2021 LAF Case Study Investigation (CSI) programme. A series of performance metrics were firstly selected according to the design goals and other associated benefits. The selected metrics include the number of observed species, frequency of using cars and alternative transport, and pollutant load reduction. These metrics were then evaluated by using a range of methods, including a resident survey, on-site measurements, and the Pathfinder landscape carbon calculator. Apart from these standardised CSI evaluation methods, we have also applied some innovative or modified methods as many standardised CSI methods are developed in the North American context, with embedded North American standards or requiring specific datasets that are not available in New Zealand. These innovative and modified methods include iNatualist data queries, a modified System for Observing Play and Recreation in Communities (SOPARC), and a modified Watershed Treatment Model (WTM). The evaluation results show that Te Whāriki generally performs well and has met most of its design goals. We also found that the wetlands and walking tracks within the residential landscape are significant in encouraging the residents to exercise more, and contribute to their self-reported improved mode and quality of life. The evaluation also identified lessons learned from the management and maintenance practices, including the need for more interpretive information regarding the use of edible elements of the landscape. This presentation aims to 1) share the key findings and lessons learned from this evaluation, 2) highlight the innovative and modified evaluation methods we applied in our evaluation, and 3) building upon past discussions related to the CSI evaluation framework (De Almeida & Lopresto, 2019; Yang et al., 2016), offer a series of reflections on the CSI framework, related to broader issues around landscape performance evaluation practices. By sharing these findings and reflections, we hope to catalyse further conversations on the current evaluation framework and contribute to its further iteration and improvement.