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 77 Factsheet 5 - Parklands to Waimairi Beach Parklands, Queenspark and Waimairi Beach street-by-street level in the days immediately after each 5.1 Ground conditions and groundwater Table C5.2 - Summary of ground elevation and groundwater depth (February 2012) Regional geology maps show this area is generally earthquake, and then on a property-by-property level over Suburb Ground elevation above sea level Groundwater depth underlain by sand of fixed and semi-fixed dunes of marine the following weeks. This mapping was supported by air- origin. The southwest area of Parklands is underlain by photo analysis for all four main earthquakes, and additional Parklands Typically 3.3m to 4.6m (Avg 4.0m) Typically 0.8m to 1.9m (Avg 1.2m) sand, silt, and some peat of drained lagoons and estuaries, regional or street-level mapping for the earthquakes of 13 Queenspark Typically 3.2m to 4.2m (Avg 3.5m) Typically 1.3m to 2.2m (Avg 1.6m) June 2011 and 23 December 2011. This additional mapping all of Holocene age deposition. Waimairi Beach Typically 3.0m to 5.5m (Avg 3.8m) Typically 1.5m to 4.1m (Avg 2.2m) indicated that the overall pattern of liquefaction and lateral Table C5.1 summarises the area-wide subsurface ground spreading for the subsequent earthquakes was generally investigations undertaken by EQC in this area following similar to that observed in the first two main earthquakes. Table C5.3 - Summary of liquefaction and lateral spread observations for residential land, aggregated the 4 September 2010 and 22 February 2011 earthquakes. from mapping undertaken following earthquakes of 4 September 2010 and 22 February 2011 These investigations indicate that the near-surface soil Figure C5.1 and Table C5.3 present a summary of the profile in the area generally comprises loose to dense sands, property-by-property rapid mapping of liquefaction and silts and some clayey silt. lateral spread observations in this area. The observations following the 4 September 2010 and 22 February 2011 Table C5.2 summarises typical ground elevation and earthquakes have been aggregated by assigning each groundwater depths in the area (the values listed correspond property the most severe observation from either of these to the 10th and 90th percentiles and the median). This was two earthquakes. These observed liquefaction and lateral derived from LiDAR ground elevation survey commissioned by spread mapping colours have completely different meaning EQC in February 2012, and a groundwater surface developed Suburb to the colour codes used by the Canterbury Earthquake from recent EQC groundwater monitoring in conjunction 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 spreading, No lateral quantities of but large ejected material to major Moderate ejected spreading, lateral often observed material spreading, lateral Severe often ejected material observed Recovery Authority (Cera) for residential land zoning with historic Environment Canterbury groundwater data. Parklands 1874 1% 29% 14% 51% 2% 2% 0% and the Department of Building and Housing (DBH) for This area is generally moderately elevated above sea level Queenspark 883 3% 5% 14% 63% 15% <1% 0% technical categories. with a shallow to moderate depth to groundwater. Waimairi Beach 626 2% 78% 5% 12% 3% 0% 0% Table C5.4 summarises the change in ground elevation The ground conditions and groundwater in this area are inferred from the LiDAR survey. The total change in ground generally similar to, or slightly more favourable than, most elevation which has occurred is a combination of regional Table C5.4 - Changes in ground elevation inferred from LiDAR survey of the eastern suburbs of Christchurch. uplift or subsidence due to fault movements (tectonics) Suburb Change in ground elevation from July 2003 to February 2012 While ground surface disturbance has occurred in some and local ground subsidence due to liquefaction and related (positive values are uplift, negative values are subsidence) areas (e.g. settlement, cracking and ejection of material), effects. The LiDAR is of limited accuracy (about ±100mm). Parklands Typically -450mm to -150mm (Average -300mm) the underlying ground which liquefied appears to have now This means that the LiDAR is more suitable for measuring Queenspark Typically -600mm to -250mm (Average -400mm) returned to its pre-earthquake strength. large changes in ground elevation (greater than about 100 Waimairi Beach Typically -550mm to -100mm (Average -300mm) to 200mm), and may not accurately represent areas where 5.2 Post-earthquake observations only minor changes in ground elevation have occurred. Rapid mapping of liquefaction and lateral spreading observations was undertaken following the 4 September 2010 Table C5.5 summarises the extent and severity of observed and 22 February 2011 earthquakes, first on a regional and liquefaction and lateral spread. Table C5.1 - 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) Parklands 15 1 15 - Queenspark 14 1 14 - Waimairi Beach 3 1 3 - ENVIRONMENTAL AND ENGINEERING CONSULTANTS EARTHQUAKE COMMISSION: Canterbury Earthquakes 2010 and 2011 - Land report as at 29 February 2012 78 Factsheet 5 - Parklands to Waimairi Beach Parklands, Queenspark and Waimairi Beach Table C5.5 - Liquefaction and lateral spread observations Unmapped, no observations (uncoloured) No lateral spreading but large quantities of ejected material No observed ground cracking or ejected liquefied material Moderate to major lateral spreading; ejected material often observed Suburb Observations Minor ground cracking but no observed ejected liquefied material Severe lateral spreading; ejected material often observed No lateral spreading but minor to moderate quantities of ejected material Territorial Authority suburb boundary Parklands Widespread minor to moderate liquefaction across much of the suburb (severe liquefaction in a small number of cases), causing sand ejection and settlement. 13TH AVENUE In some areas, settlement and minor ground cracking observed without any obvious surface evidence of liquefaction, likely due to minor liquefaction occurring at depth below the surface but not being ejected. GOLF ROAD LOWER STYX ROAD Some localised areas of moderate to major lateral spreading, towards the wetland and small watercourses, or in areas of more steeply sloping ground. 16TH AVENUE For the remainder of the suburb (the northwest and southeast), no surface evidence of liquefaction or related land effects was observed. UNIFORM ROAD Queenspark Widespread minor to moderate liquefaction across most of the suburb (severe liquefaction on many 17TH AVENUE lower-lying roads and some residential properties), causing sand ejection and settlement. In some areas, the extent of liquefaction from the earthquake of 13 June 2011 was greater than tabulated for the first two main earthquakes in Table C5.3. ECHO ROAD TANGO ROAD In some areas, settlement and minor ground cracking observed without any obvious surface evidence of 18TH AVENUE LIMA ROAD liquefaction, likely due to minor liquefaction occurring at depth below the surface but not being ejected. INDIA ROAD DANS ROAD KILO ROAD Some localised areas of minor to moderate lateral ground movements, in areas of more steeply sloping 19TH AVENUE ground. NOVEMBER ROAD Waimairi Beach For the western portion of the suburb (along Bower Ave), widespread minor to moderate liquefaction FOXTROT ROAD 20TH AVENUE (severe liquefaction in a small number of cases), causing sand ejection and settlement.