The Christchurch Southern Motorway: Stage Two (CSM2) has just received Resource Management Act permissions from the Board of Inquiry. The 17 km route commences at Halswell Junction Road and travels southwest to Rolleston.
The Puhoi to Warkworth Project realigns the existing SH1 from the Northern Gateway Toll Road at the Johnstone’s Hill tunnels via an 18.5 km four-lane dual carriageway road alignment that will tie into the existing SH1 north of Warkworth.
This paper examines how the site visits, stream surveys and hydraulic model were used to develop options for longer-term betterment which would enhance all six values.
Mauri is a concept that permeates Māori thinking; it is the binding force that holds together the physical and spiritual components of a being or thing. The mauri model was created to include Māori perspectives appropriately in evaluation and decisionmaking. The model incorporates four key factors: mauri of the environment (integrity of the ecosystem), mauri of the hapu (integrity of cultural identity), mauri of the community (integrity of society), and mauri of the whanau (economic integrity).
The approach focuses on reducing the generation of stormwater runoff and contaminants, and then managing them at source, using land use controls in conjunction with discharge provisions. It also seeks to minimise adverse effects of new development and progressively reduce existing effects at the time of redevelopment. There were significant challenges associated with integrating this approach across the Plan which are explored in this paper.
Earthquakes have been a game-changer for urban stormwater catchment management planning in Christchurch. The Avon Stormwater Management Plan (SMP) is the first fully post-earthquake SMP. Setting up the SMP framework is different because of the earthquakes. This paper discusses the opportunities and challenges that have confronted the developing Avon SMP. Channel morphology and hydrology have changed, the central city has changed and the future of the residential red zone has not yet been decided – what assumptions can we reasonably make? Changes in land use, fast tracking of urban expansion and subdivisions required re-working of planning implications and re-analysing stormwater effects on waterways.
Elevated discharge water temperature is gaining international recognition as a contaminant of concern to receiving waterways. Maintaining suitable thermal conditions in waterways is critical to stream health, and guidance is required for the assessment and management of stormwater temperature effects on freshwater receiving environments.
The Auckland Council Stormwater Unit’s regional approach to obtain network discharge consents is based on 10 large coastal water bodies (Consolidated Receiving Environments), which include the Waitemat? and Manukau Harbours. Since amalgamation, the Stormwater Unit has evolved from the transition of operations from legacy councils to the transformation of stormwater management across Auckland.
This paper discusses the development of the WSD Assessment Tool. Information is also provided on the mechanics of how the tool operates, and how outcomes produced from the tool can be interpreted to enable improved inclusion of WSD principles within development form.
This paper will review the site issues and rehabilitation objectives, discuss the landscape-led concept options approach and highlight the method of producing an integrated, multiple-benefit storm water project.
This paper briefly describes historic methodologies and outlines the planned upgrades for HIRDS Version 4. The aim of the upgrade is to search out and expand New Zealand’s rainfall dataset to improve coverage, include recent storms, and include historic paper records. The proposed upgrade will carry out analysis to extend the average recurrence interval to the 250 year return period, provide areal reduction curves and temporal patterns for design storms.
New Zealand is seeing the biggest change in water management legislation since the Resource Management Act became law in 1991. The National Policy Statement for Freshwater Management is setting water quality and quantity limits with a return to catchment management planning. Roading networks double as stormwater networks, due to their linear nature, roads cut across or down catchments.
This paper discusses the Avon River Precinct, a world class urban design project, with a focus on the low impact stormwater design elements of the project, the process of working in a project led by urban designers and some of the challenges along the way. The final result, is a shining example of how stormwater management can be more than a utilitarian asset, instead forming a core element of the urban design aesthetic with the added benefit of managing stormwater.
This paper describes TCC’s inclusive approach to stormwater management. It covers the development of an overarching sub-regional flood risk management strategy in conjunction with BoPRC, Western Bay of Plenty District Council and community stakeholders which will set out roles, responsibilities and a whole of catchment approach for TCC’s stormwater catchment management planning.
This study addresses the effect of different inlet and outlet configurations and the influence of baffles on the hydraulic performance of a model pond. The physical model is a trapezoidal pond with top dimensions of 4.1 × 1.6 m × 0.3 m deep and side and end slopes of 2:1.Three perforated T-bars were fixed to an outlet riser to simulate a floating decant dewatering system.
Stormwater has been recognised as one of the major sources of diffuse pollution to the aquatic environments. Several studies have shown that stormwater can contribute to the deterioration of water and sediment quality of a waterway. To correctly manage the pollution sources in stormwater it is beneficial to understand the main sources during dry and wet weather events.
Increases in downstream water temperatures and potential effects on stream life as a result of on-line stormwater ponds is an issue that is currently receiving some attention. Most of the research experience on such temperature effects has been around existing small ponds with no New Zealand before and after case study examples.
This paper explores some innovative approaches being used in Australia to inform decision makers managing “flashy” catchments. These approaches focus on leveraging readily available hydrologic, hydraulic and infrastructure spatial datasets, along with forecast rainfall amounts to rapidly provide real-time intelligence on what will be affected by the impending flood.
This paper presents the challenges and outcomes of the design process and provides details on the complex issues of stormwater asset management in the Chelsea Estate Heritage Park.
The adjacent urban areas of Richmond and Stoke within the adjoining Tasman and Nelson Districts suffered from an extreme rainfall event on 21 April 2013 causing approximately $35 million damage within a few hours.
This paper discusses the success of the Ashburton stormwater model development, how the process has led to many benefits not immediately obvious and how it has been used to inform council decision making and long term asset management. Key to this was the ‘hands on’ approach taken by the team and the utilization of easy to interpret visual outputs. This enabled immediate buy in from the councilors allowing staff to move quickly to using the model for long term stormwater management planning.
During emergencies, time is a critical factor in successful outcomes. When producing emergency action plans mapped results of time to peak velocity and time to peak water depth can greatly assist. Time of inundation maps can be produced identifying the time from the start of an event to the depth at which is no longer safe to walk in water, or no longer safe to drive a car for evacuation purposes.
Coinciding with the Unitec environmental sustainability strategy daylighting of the Wairaka stream is at the heart of creating positive environmental change on campus. Currently part of the stream flows through a 70m culvert hiding away its historic character and lessening its natural benefits. The paper analyses potential daylighting designs, and details a final design. A Stream Ecological Valuation performed on the downstream reach produced a baseline score of 0.58, indicating moderate water quality.