Report 1 - Executive Summary

Background

Waitakere City Council obtained funding from the Ministry for the Environment's sustainable Management Fund in 1999, to develop and implement a comprehensive strategy and action plan for the sustainable management of urban stormwater within Waitakere City.

The overall scope of the project was to develop a broad level methodology for the development of a comprehensive urban stormwater management action strategy that could also provide guidance to other territorial local authorities.

Key objectives of the project were to focus attention on the following aspects of stormwater management:

• Improvement in water quality
• Reduction in the potential for flooding
• Restoration of watercourses as far as is practicable in the amenity of watercourses and restoration of habitat
• Provision of recreational facilities in association with water management facilities
• Beneficial use of run-off water from the catchment

The project was divided into 1five broad phases as detailed below:

First Phase:   Research and collation of existing extensive information base into a series of draft reports, guidelines, and standards

• Ranking stormwater catchments based on catchment issues rating and receiving environment conditions, using a computer-based decision model [Report 8]
• Using above information to develop possible scenarios for catchment improvement [Report 3].
• Preparation of a Stormwater Strategy [Report 4]: - Identifying key issues for the various stormwater catchments [Table 3: Key issues for Waitakere City stormwater management units]. - enveloping detailed long-term financial strategy costs, annual plan costs and as a guide to future works programmes. [Sec. 3. Stormwater Management: Issues, objectives, policies, explanations, implementation methods and monitoring]
• Preparation of draft Codes of Practice for sustainable stormwater management, including requirements for Greenfield subdivisions [Report 5]
• Preparation of guidelines for source control methods and programmes - especially for industry [Report 6]
• Preparation of guidelines for beneficial reuse of stormwater [Report 7]
• Review receiving environment condition rating by carrying out a preliminary environmental effects assessment [Report 8: Receiving Environment Quality in Waitakere City]. This programme was also to be used to develop the long-term environmental monitoring programme
• Develop and instigate a long-term environmental monitoring programme [Report 9: Stormwater Monitoring Programme]

Second Phase: Community Consultation Process

• Internal and external stakeholders including iwi, and guest speakers from the Auckland Regional Council and Earth Consult, invited to a series of one day workshops [Report 12]:

- Catchment Prioritisation Workshop
- Identifying Solutions for Catchments
- Developing a Stormwater Strategy Statement

• Develop an integrated stormwater management strategy with input from key stakeholders [Report 4]
• Three Waters public awareness and education programme launched in October 2000 [Report 12]

Third Phase: Review and final drafting of guidelines and reports

Fourth Phase: Implementation of demonstration projects

The fourth phase of the programme involved the implementation of demonstration projects, such as managed rainwater tanks, infiltration techniques, riparian planting and habitat improvement, and a 'soft engineering' approach to stormwater runoff control [Report 10].

Fifth Phase: Development of an Integrated Strategy

• The fifth phase of the programme involved finalising the Comprehensive Urban Stormwater Management Strategy and Action Plan [Report 4].
• Prioritisation of the catchments (stormwater management units) using a number of criteria and the computer-based model [Table 9]
• Development of issues, objectives and integrated policies for stormwater management, including implementation methods and monitoring [Sec. 3]
• Report on the costs and benefits estimated for urban stormwater management [Tables 10 & 11]

The following reports were developed in this final phase of the project:

Documentation of the project

In order to record alternative sustainable management options for the Council (and other authorities and utilities throughout New Zealand), the development of twelve reports, listed below, was fundamental to the project.  As each draft report was completed, it was circulated to the appropriate stakeholders for comments and feedback.  Final drafts have been lodged with the Ministry for the Environment as project outputs.

As a condition of the Council's contract with the Ministry for the Environment, all territorial authorities in the Auckland Region, all Regional Councils and those territorial authorities with a population of over 100,000 persons have been sent complimentary copies of this Executive Summary (Report 1); the Stormwater Strategy (Report 4); and the Guidelines (Reports 5, 6 & 7). In addition a copy of this Executive Summary has also been distributed to all other territorial authorities in New Zealand.

The full list of reports is as follows:

Note:   Report 11 comprises a series of Information, Issues and Options Reports, one for each of 19 of Waitakere City's urban stormwater management units or catchments.