REPORT LAKE HOOD EXTENSION PROJECT JOINT VENTURE Lake Hood Aquatic Park Extension Assessment of Environmental Effects Report prepared for: LAKE HOOD EXTENSION PROJECT JOINT VENTURE Report prepared by: TONKIN & TAYLOR LTD Distribution: LAKE HOOD EXTENSION PROJECT JOINT VENTURE TONKIN & TAYLOR LTD (FILE) December 2008 T&T Ref: 50977.303 PART 1 OF 2 Table of contents 1 Introduction 1 1.1 Background 1 1.2 The Applicant 1 1.3 Other Parties’ Involvement 2 1.4 Existing Use and Development of the Park 2 1.5 Resource Consents Sought 3 1.5.1 New Consents 3 1.5.2 Variations to Existing Consents 5 1.6 Scope of Report and Supporting Documentation 12 1.7 Other Approvals 13 2 Description of the Site 14 2.1 Location 14 2.2 Legal Description 14 2.3 Site Area 14 2.4 The Existing Environment 15 2.4.1 Existing Aquatic Park 15 2.4.2 Existing Land Use of the Proposed Site 16 2.4.3 Surface Waterways 16 2.4.4 Groundwater 17 2.4.5 Water Quality and Ecology of the Existing Lake 17 2.4.6 Heritage Values and History of Riversdale 20 2.4.7 Archaeological Sites and Cultural Values 21 2.4.8 Ecological Values 21 2.4.9 Surrounding Environment 21 3 Proposed Aquatic Park Extension – Vision and Concept Design 22 3.1 Project Vision 22 3.2 Concept Design 22 4 Aquatic Park Creation 25 4.1 Overview 25 4.2 Staging 25 4.3 Lake Creation 27 4.3.1 Introduction 27 4.3.2 Material Extraction 28 4.3.3 Management of Extracted Material 28 4.3.4 Water and Sediment Management 30 4.3.5 Removal of Material from Site 30 4.3.6 Crossing of Ashburton River 30 4.3.7 Water Sources for Extended Lake 34 4.3.8 Lake Water Retention Structures 34 4.3.9 Dam Safety 35 4.3.10 Hours of Operation 35 4.3.11 Site Offices 36 4.3.12 Management Plan 36 5 Aquatic Park Development 37 5.1 Introduction 37 5.2 Access 37 5.3 Riversdale Homestead 38 Lake Hood Aquatic Park Extension Assessment of Environmental Effects T&T Ref. 50977.303 LAKE HOOD EXTENSION PROJECT JOINT VENTURE December 2008 5.4 Residential Areas 38 5.4.1 Rural-Residential 38 5.4.2 Lower-Density Residential – The Canals 39 5.4.3 Higher-Density Residential and Commercial - The Village 39 5.5 Recreation Island 39 5.6 Lake Extension 40 5.7 Open Space Network 40 5.8 Transmission Line Corridor 41 5.9 Infrastructure 42 5.9.1 Water Supply 42 5.9.2 Wastewater 43 5.9.3 Stormwater 44 6 Statutory Assessment 46 6.1 Introduction 46 6.2 Resource Management Act 1991 (RMA) 46 6.3 Canterbury Regional Policy Statement 48 6.3.1 Chapter 8: Landscape, Ecology and Heritage 48 6.3.2 Chapter 9: Water 49 6.3.3 Chapter 10: Beds of Rivers and Lakes and their Margins 49 6.3.4 Chapter 15: Transport 50 6.4 Transitional Regional Plan 51 6.5 Proposed Natural Resources Regional Plan 51 6.5.1 Chapter 2: Ng āi Tahu and the Management of Natural Resources 51 6.5.2 Chapter 3: Air Quality 52 6.5.3 Chapter 4 - Water Quality 53 6.5.4 Chapter 5: Water Quantity 55 6.5.5 Chapter 6 – Beds and Margins of Lakes and Rivers 56 6.5.6 Chapter 7: Wetlands 57 6.5.7 Chapter 8: Soil Conservation 58 7 Consultation 59 8 Assessment of Environmental Effects and Proposed Mitigation 65 8.1 Introduction 65 8.2 Effects of Lake Creation on Groundwater 65 8.2.1 Introduction 65 8.2.2 Effects on Groundwater Levels 66 8.2.3 Effects on Existing Groundwater Users 66 8.2.4 Groundwater Flows To and From Lake Hood 68 8.3 Effects of Lake Creation on Ashburton River 69 8.3.1 Ashburton River Gains and Losses 69 8.3.2 Effects on Instream Habitat 70 8.4 Effects of Stormwater Discharge 70 8.5 Aquatic Ecology of the Extended Lake and Associated Surface Waterways 73 8.5.1 Introduction 73 8.5.2 Predicted Aquatic Ecology 73 8.6 Water Quality of the Extended Lake 74 8.6.1 Introduction 74 8.6.2 Management of Water Quality 74 8.7 Effects of River Crossing 80 Lake Hood Aquatic Park Extension Assessment of Environmental Effects Job no. 50977.303 LAKE HOOD EXTENSION PROJECT JOINT VENTURE December 2008 8.7.1 Introduction 80 8.7.2 Effect on Hydrology of Ashburton River 81 8.7.3 Effect on Instream Habitat of Ashburton River 82 8.7.4 Effect on Infrastructure 84 8.7.5 Summary 84 8.8 Flood Hazard 84 8.9 Effects on Air Quality 85 8.9.1 Introduction 85 8.9.2 Potential for Dust Generation 86 8.9.3 Sources of Dust Generation and Mitigation Options 88 8.9.4 Dust Management Plan 89 8.9.5 Summary 90 8.10 Economic Impact Assessment 90 8.10.1 Introduction 90 8.10.2 Financial Outcomes for Lake Hood Developer 90 8.10.3 Other Costs and Benefits 91 8.10.4 Increased Economic Activity in the District 92 8.10.5 Summary 93 8.11 Effects on Historical, Cultural & Archaeological Values 94 8.12 Effects of Lake Creation on Electricity Transmission Lines 95 8.13 Effects on the Rural Land Resource 96 9 Conclusion 97 10 Applicability 99 Appendix 1: Location and Site Plans Appendix 2: Certificates of Title Appendix 3: Project Staging Plans Appendix 4: Proposed River Crossing Lake Hood Aquatic Park Extension Assessment of Environmental Effects T&T Ref. 50977.303 LAKE HOOD EXTENSION PROJECT JOINT VENTURE December 2008 Executive summary Lake Hood is a man-made, community-based recreational lake located approximately 7 km south of Ashburton (see Location Plan in Appendix 1). The lake forms the central focus for an aquatic park, which also includes an associated residential area known as Huntingdon Park. The lake and its associated facilities are open to the public, for use by the local, district, regional and national community. Lake Hood and the associated land within the aquatic park are managed and operated by the Ashburton Aquatic Park Charitable Trust (AAPCT). The Lake Hood Aquatic Park has become a popular and attractive place to live and a recreational destination of high demand. In order to meet the increased recreational and residential demand, the Lake Hood Extension Project Joint Venture has been formed to extend the Aquatic Park. The Joint Venture is a consortium comprising the AAPCT, Riversdale Farm Ltd, and Ashburton Contracting Ltd. The existing lake and its recreational and residential surrounds are currently covered by resource consents granted by Environment Canterbury. The extension of the Aquatic Park is the subject of this application for resource consents to Environment Canterbury. The applicant is the AAPCT. The existing facilities are also specifically catered for by way of zoning in the Ashburton District Plan. An extension of the Aquatic Park Zone (APZ) to provide for the extended Aquatic Park is also being sought by AAPCT from the Ashburton District Council through a private plan change process. The applications for resource consent and private plan change seek to enable an extension to the Lake Hood Aquatic Park, including the construction and maintenance of a recreational lake and associated community and residential activities, and a crossing over the Ashburton River adjacent to the site for project- related traffic. The area over which the extension is sought is situated immediately north of the existing Lake Hood. Most of the area comprises Riversdale Farm, owned by one of the Joint Venture partners. A number of resource consents are required from Environment Canterbury for the creation, operation and maintenance of the lake and associated facilities. Preparation of a management plan is a key part of the ongoing management of the Lake Hood Extension Project (LHEP). New consents are sought from Environment Canterbury as well as variations to some existing consents held by AAPCT or other Joint Venture Partners. The development of the extended Aquatic Park is a long-term project. It will be undertaken in stages designed to provide immediate access to increasing areas of lake, sequenced with staged release of residential and rural-residential sections. The staging is designed to provide improved recreational facilities balanced with sale of land to fund the ongoing development of the Aquatic Park for the community. It is expected that full development could be achieved by 2020. The exact date will depend on the market for section sales. Creation of the expanded lake area is expected to be complete by approximately 2015. Lake Hood Aquatic Park Extension Assessment of Environmental Effects T&T Ref. 50977.303 LAKE HOOD EXTENSION PROJECT JOINT VENTURE December 2008 The extension to the lake will be excavated below groundwater level. Its creation will require the removal of gravel material. This material has the potential to supply Ashburton District with an assured supply of gravel aggregate for a period of in the order of 15-20 years. This is a significant benefit to Canterbury, in addition to the enhanced recreational and residential areas of Lake Hood. At full development, the extended Lake Hood will: • Provide an expanded lake area, more than doubling the existing area to approximately 180ha, improving safety for lake users. • Provide an additional 350 residential lots, of varying density, bringing the total number of lots to 500. • Retain the existing small commercial hub centred around the Lake House and provide for supporting commercial facilities in this location.