Tai Tapu to Halswell Halswell River, Lincoln and Tai Tapu
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APPENDIX C APPENDIX C The Plains - area-wide suburb technical land information Kaiapoi Lakes 1 2 North Kaiapoi Pines Beach Kairaki Beach ! South Kaiapoi Brooklands 3 Bridgend Spencerville Chaneys Ouruhia Belfast 4 5 Styx Harewood Marshland Queenspark Redwood Parklands Casebrook Waimairi Beach Northcote Bishopdale Travis North Mairehau Westhaven New Brighton Burwood Papanui New Brighton Burnside Avonhead Shirley Avondale Yaldhurst Hyde Park 6 7 8 9 Bryndwr St Albans Dallington Bexley Russley Richmond Wainoni Fendalton Merivale Ilam Avonside Aranui Riccarton Park Masham Upper Riccarton Central City North Linwood South New Brighton Templeton Riccarton Phillipstown Hei Hei Bromley Linwood 2012 CanterburyEarthquakes2010and2011-Landreport asat29February COMMISSION: EARTHQUAKE Sockburn Middleton Sydenham Waltham Islington Addington 10 11 St Martins12 13 Hornby Spreydon Woolston Ferrymead Opawa Southshore Hillmorton Somerfield Redcliffs Hoon Hay Beckenham Mt Pleasant St Andrews Hill Westlake Cashmere Oaklands Heathcote Clifton Wentworth Park Sumner Hillsborough Huntsbury Moncks Spur Scarborough Prebbleton 14 Westmorland Halswell Hoon Hay Valley Lyttelton 15 Lincoln Diamond Harbour Governors Bay Tai Tapu Port Levy Notes: DRAWN Road Database supplied by Terralink International Ltd. CHECKED TECHNICAL LAND INFORMATION Rivers, lagoons and coastline licensed under Creative FACT SHEETS Commons Attribution 3.0 New Zealand and sources from LINZ APPROVED ARCFILE Area-wide Suburbs SCALE (AT A3 SIZE) A3 SCALE 1:100,000 1:100,000 0 1 2 3 4 5 (km) PREPARED BY TONKIN & TAYLOR LTD FIGURE No. REV No. PROJECT No. 68 Location Plan 52020.0200 Map Reference Sheet 0 EARTHQUAKE COMMISSION: Canterbury Earthquakes 2010 and 2011 - Land report as at 29 February 2012 97 Factsheet 15 - Tai Tapu to Halswell Halswell River, Lincoln and Tai Tapu level mapping for the subsequent main earthquakes. 15.1 Ground conditions and groundwater Table C15.2 - Summary of ground elevation and groundwater depth (March 2011) Regional geology maps show this area is generally underlain This additional mapping indicated that the pattern of Suburb Ground elevation above sea level Groundwater depth by river alluvium beneath plains or low level terraces of liquefaction and lateral spreading for the subsequent Holocene age. earthquakes was generally similar to that observed in the Halswell River Typically 4.8m to 8.8m (Avg 6.5m) Typically 0.7m to 1.3m (Avg 1.0m) first main earthquake, but less extensive and severe. Lincoln Typically 9.1m to 13.4m (Avg 11.3) Typically 2.0m to 4.0m (Avg 3.0) Table C15.1 summarises the area-wide subsurface ground Tai Tapu Typically 6.4m to 7.0m (Avg 6.7m) Typically 0.7m to 1.3m (Avg 1.0m) investigations undertaken by EQC in this area following the Figure C15.1 and Table C15.3 present a summary of the 4 September 2010 earthquake. These investigations indicate property-by-property rapid mapping of liquefaction and that the near-surface soil profile in the area generally lateral spread observations undertaken by EQC in this Table C15.3 - Summary of liquefaction and lateral spread observations for residential land, comprises very loose to dense sands, gravels, silts and clays. area. The mapping undertaken by EQC was predominantly aggregated from mapping undertaken by EQC following earthquake of 4 September 2010 of the main urban areas of Lincoln and Tai Tapu, with less Table C15.2 summarises typical ground elevation and detail in the surrounding rural areas. For more extensive groundwater depths in the area (the values listed correspond and detailed mapping of liquefaction observations in these to the 10th and 90th percentiles and the median). This was rural areas, refer to the post-earthquake liquefaction report derived from LiDAR ground elevation survey commissioned commissioned by the Selwyn District Council, available at by the Ministry of Civil Defence and Emergency Management http://www.selwyn.govt.nz/services/building/earthquake- in March 2011, and a groundwater surface developed from building-recovery/liquefaction-report. These observed historic Environment Canterbury groundwater data. This area liquefaction and lateral spread mapping colours have Suburb is generally elevated moderately well above sea level with a completely different meaning to the colour codes used by residential Total property count Not mapped ground No observed or ejected cracking liquefied material cracking, Minor ground ejected but no observed liquefied material but spreading, No lateral quantities minor to moderate of ejected material to major lateral Moderate quantities or large spreading of ejected material spreading, lateral Severe often ejected material observed shallow to moderate depth to groundwater. the Canterbury Earthquake Recovery Authority (Cera) for Halswell River 391 61% 17% 0% 22% 0% 0% The ground conditions and groundwater in this area are residential land zoning and the Department of Building and Lincoln 1168 <1% 99% 0% 0% 0% 0% generally similar to, or slightly more favourable than, most of Housing (DBH) for technical categories. Tai Tapu 174 3% 90% 0% 7% 0% 0% the southern, central and northern suburbs of Christchurch Table C15.4 summarises the change in ground elevation While ground surface disturbance has occurred in some inferred from the LiDAR survey. The total change in ground Table C15.4 - Changes in ground elevation inferred from LiDAR survey areas (e.g. settlement, cracking and ejection of material), elevation which has occurred is a combination of regional Suburb Change in ground elevation from February 2008 to March 2011 the underlying ground which liquefied appears to have now uplift or subsidence due to fault movements (tectonics) (positive values are uplift, negative values are subsidence) returned to its pre-earthquake strength. and local ground subsidence due to liquefaction and related Halswell River Typically -200mm to +50mm (Average -100mm) effects. The LiDAR is of limited accuracy (about ±100mm). 15.2 Post-earthquake observations This means that the LiDAR is more suitable for measuring Lincoln No data (beyond extent of pre-earthquake LiDAR coverage) Rapid mapping of liquefaction and lateral spreading large changes in ground elevation (greater than about 100 Tai Tapu Typically -200mm to +0mm (Average -150mm) observations was undertaken following the 4 September to 200mm), and may not accurately represent areas where 2010 earthquake, first on a regional and street-by-street only minor changes in ground elevation have occurred. level in the days immediately after the earthquake, and then on a property-by-property level in urban areas over the Table C15.5 summarises the extent and severity of observed following weeks. This mapping was supported by regional- liquefaction and lateral spread. Table C15.1 - Area-wide geotechnical investigations undertaken by EQC (December 2011) Suburb Number of cone Number of Number of groundwater Length of MASW penetration tests boreholes standpipes geophysical testing (m) Halswell River - - - - Lincoln - - - - Tai Tapu 7 - - - ENVIRONMENTAL AND ENGINEERING CONSULTANTS EARTHQUAKE COMMISSION: Canterbury Earthquakes 2010 and 2011 - Land report as at 29 February 2012 98 Factsheet 15 - Tai Tapu to Halswell Halswell River, Lincoln and Tai Tapu Table C15.5 - Liquefaction and lateral spread observations Unmapped, no observations (uncoloured) No lateral spreading but minor to moderate quantities of ejected material No observed ground cracking or ejected liquefied material Moderate to major lateral spreading or large quantities of ejected material Suburb Observations Minor ground cracking but no observed ejected liquefied material Severe lateral spreading; ejected material often observed Territorial Authority suburb boundary Halswell River Minor to moderate liquefaction in many rural areas alongside the Halswell River and other watercourses, causing sand ejection and settlement. Minor lateral spreading in some localised areas alongside the Halswell River. LEADLEYS ROAD For the remainder of the area, no surface evidence of liquefaction or related land effects was observed. Lincoln No surface evidence of liquefaction or related land effects observed. Tai Tapu Minor to moderate liquefaction in several small areas, causing sand ejection and settlement. For the remainder of the urban area, no surface evidence of liquefaction or related land effects was observed. ROBINSONS ROAD MCDRURYS ROAD SPRINGS ROAD For further area-wide geotechnical information, refer to the technical data reports BIRCHS ROAD on the EQC website, at http://canterbury.eqc.govt.nz/news/reports ROADTAPU OLDTAI HAYES ROAD OSTERHOLTS ROAD OSBORN ROAD HOLMES ROAD BARNES ROAD BOUNDARY ROAD SETTLEMENT ROADTANCREDS ROAD TAI TAPU ROAD Linwood, North Linwood, Opawa, Phillipstown, St Martins, WalthamVOSS ROAD & Woolston NORTH BELT Lincoln GERALD STREET EDWARD STREET SOUTH BELT RAINEYS ROAD MEYER ROAD BARNES ROAD PERYMANS ROAD MOIRS LANE RHODES ROAD LINCOLN TAI TAPU ROAD COLLINS ROAD ELLESMERE ROAD POPLAR LANE COLLINS ROAD EAST WARDSTAY ROAD SCHOOL ROAD Tai Tapu DAVIS ROAD HUDSONS ROAD MCDONALD ROAD CHRISTCHURCH AKAROA ROAD GILMOURS ROAD ENGLISHS ROAD CARTERS ROAD RIVER ROAD GREENPARK ROAD Applicability - This report was prepared and/or compiled for the Earthquake Commission (EQC) to communicate information that may be relevant to residential land claims under the Earthquake Commission Act 1993. The report was not intended for any other purpose and may not be relied upon for any other purpose. EQC and its engineers, Tonkin & Taylor, have no liability to any user of any map(s) and data in this report or for the consequences of any other person relying on them in any way. This Figure C15.1 - Overview of liquefaction and lateral spreading observations, from mapping undertaken following the information is not intended to form a complete technical report on land changes in all or any part of Canterbury. earthquake of 4 September 2010. ENVIRONMENTAL AND ENGINEERING CONSULTANTS.