Water sensitive cities can use groundwater as a sustainable non-potable water source, improve management of groundwater recharge, and mitigate impacts of shallow groundwater on urban developments.
Waterway naturalisation is the process of converting drainage channels into a more naturalised state, typically mimicking to some extent the former history of the waterway, reverting back to a more natural system.
Our extensive research has uncovered some valuable information on natural systems, for example:
- Annual subsurface drainage flows provide multiple times the annual irrigation demand if wet season flows are stored and reused by aquifer storage and recovery. (Urban subsurface drainage as an alternative water source in a drying climate)
- Urbanisation with stormwater infiltration affects the whole catchment water balance and increases the probability of groundwater seepage above terrain. (Hydrologic impact of urbanization with extensive stormwater infiltration)
- Managed aquifer recharge is increasingly used worldwide to store treated wastewater and stormwater for later use. However, several legal frameworks for governing managed aquifer recharge can be considered: rights to access alternative water resources; legal requirements concerning the quality and quantity of recharged water; and rights to extract recharged water. (Regulatory renovation for managed aquifer recharge using alternative water resources: a Western Australian perspective)
- Soils in the riparian zone (next to waterways) may decrease nitrogen loads to streams through microbial transformations. (Soil microbes of an urban remnant riparian zone have greater potential for N removal than a degraded riparian zone)
- When repairing degraded streams, planting woody riparian vegetation can reduce nitrogen concentrations in surface water and fluvial sediments. (Multi-scale characterisation of stream nutrient and carbon dynamics in sandy near coastal catchments of south-western Australia)
- A study of the Swan Canning catchment-estuary system used simulated water and nutrient generation and export to predict nutrient loads under future land use and climate scenarios, and to scope potential future management changes through scenario testing. (Hydrological and nutrient modelling of the Swan Canning catchment-estuary system)
You will find a range of research reports on natural systems under the categories below.
- The impact of urbanisation and stormwater management practices on water balances and nutrient pathways in areas of high groundwater: a review of recent literature
- Impact of water allocation strategies to manage groundwater resources in Western Australia: Equity and efficiency considerations
- Urban subsurface drainage as an alternative water source in a drying climate
- Hydrological impact of urbanisation with extensive stormwater infiltration
- Determining the extent of groundwater interference on the performance of infiltration trenches
- Regulatory renovation for managed aquifer recharge using alternative water resources: a Western Australian perspective
- Integrated Research Project 5: Knowledge-based water sensitive city solutions for groundwater impacted developments
- Effectiveness of nitrogen removal using urban wetlands - summary report
- Brabham Action Learning Partnerships: Case report
- Enabling water sensitive urban development: planning and governance opportunities for Perth
- Minimising fill in low lying urban land
- Application of machine learning algorithms for nitrogen prediction in urban areas
- Application of machine learning algorithms for nitrogen prediction in urban catchment
- Groundwater control and supply for sustainable urban development
- Performance of two urban stormwater biofilters in an area with seasonally high groundwater
- The most cost-effective ways to maintain public open space with less water: Perth case study
Our research on natural systems has been applied to a range of projects, for example:
- The first of its kind in Australia, the WA Groundwater Replenishment Trial explores how the idea to recycle and recharge water gained traction, how the processes of testing and development were managed, and how eventual acceptance of groundwater replenishment as a new source of water was achieved within water licencing and regulatory arrangements and community perceptions.
- Naturalising the deteriorated sections of the concreted banks of the Cooks River allowed for planting of native plants, created activated spaces and increased the habitat for birds and aquatic life.
- Testing the viability of improving waterway health through catchment retrofit improved the health of Dobsons Creek, a high ecological value waterway, with stormwater disconnection.
- An economic study was undertaken on one of the many drains in the heavily urbanised Bannister Creek catchment that were converted to a living streams and wetlands.
- This case study examined transforming an existing concrete channel into a natural waterway that is located in a heavily urbanised area over 5 years.
- The RESTORE Tool was applied to four sites along Scrubby Creek, demonstrating its use in undertaking rapid assessments of waterways and identifying management priorities.
You will find examples of research application on natural systems under the categories below.
- White Gum Valley case study
- WA groundwater replenishment trial: A case study of creating the enabling environment for regulatory change
- Ideas for Townsville
- Ideas for Ocean Reef Marina
- Ideas for Brabham
- Ideas for Bentley
- Queensland Children’s Hospital therapeutic landscapes
- Green walls, roofs and facades in the City of Melbourne
- Victorian Planning Provisions Amendment (V154 – Stormwater management) case study
- Marrickville West Primary School eco water garden
- Wanyarram Dhelk case study
- Resource recovery from wastewater
- Kunshan Ring Road case study
- Sydney water bank naturalisation
- Dobsons Creek stormwater disconnection project
- Forest Park ecological wetland case study
- Bannister Creek living stream case study
- Enhancing our Dandenong Creek program case study
- Small Creek naturalisation case study
- Glenelg to Adelaide Pipeline (GAP) case study
- Ideas for a Water Sensitive Sydenham to Bankstown Urban Renewal Corridor
- Assessment of non-market benefits of implementing large-scale WSUD: Greening the pipeline case study
- RESTORE Tool evaluation – Scrubby Creek pilot application
Tools and guidelines
Several tools, guidelines and frameworks have been developed for use by practitioners including:
- INFFEWS tools, including the Value Tool and Benefit Cost Analysis Tool, can be used to monetise non-market costs and benefits relating to rehabilitation or protection of natural systems.
- INFFEWS Benefit Cost Analysis Tool: Booklet of applied examples documents how the BCA Tool was applied to case studies including the naturalisation of Taralla Creek.
- The RESTORE Tool is a decision making tool to support the holistic repair of urban waterways. The tool helps identify ecosystem components that will deliver the best ecological results for restoration of urban waterways.
- A guide for monitoring the performance of WSUD elements in areas with high groundwater provides recommendations for monitoring nutrient removal performance of water sensitive urban design (WSUD) elements and presents an overview of monitoring and analysis techniques in areas where high groundwater may influence WSUD element performance.
Conceptual model of perturbation of the urban water balance (Ocampo CJ, 2018. The impact of urbanisation and stormwater management practices on water balances and nutrient pathways in areas of high groundwater: A review of recent literature. Melbourne, Australia: CRC for Water Sensitive Cities, p. 14.)
Different sources of infiltration in the urban karst (Ocampo CJ, 2018. The impact of urbanisation and stormwater management practices on water balances and nutrient pathways in areas of high groundwater: A review of recent literature. Melbourne, Australia: CRC for Water Sensitive Cities, p. 19.)
Pre-development water balance (GHD, Water Technology and the University of Western Australia, 2019. Integrated Research Project 5: Stage 1 report. Melbourne, Australia: CRC for Water Sensitive Cities, p. 10.)
Simplified conceptual pre-urban development water balance factors (Claydon et al., 2020. Guiding urban water management in areas that experience high seasonal groundwater. Expert Panel report. Melbourne, Australia: CRC for Water Sensitive Cities, p. 15.)
The extent of mounding is influenced by the depth and distance between subsurface drains, and this in turn determines the volume of fill required for an urban development (CRCWSC, 2018. Ideas for Brabham. Melbourne, Australia: CRC for Water Sensitive Cities, p. 11.)