Geotech Effluent Foundation

Les Garcynski of Ruatangata wanted to site a 3 bedroom house on his newly purchased property in Ruatangata.  He wanted to take advantage of sweeping views of the local countryside.  Cook Costello provided geotechnical, effluent disposal and foundation design services.    
The house was to be positioned at the top of a steep hill.  CCL drilled boreholes and conducted a scala penetrometer test to determine soil type and strength throughout the depth of the soil. 

The stability of the slope was analysed using "slide" slope stability analysis software.  The site was determined to be stable although it was recommended that the slope be planted in vegetation. 

The foundations required design by a Chartered Professional Engineer due to the determined soil strengths.  The foundations needed to be extended to 700mm below ground level to avoid shrinking and swelling of the soils. 

Effluent design was based on 4 soakage test holes.  Due to low soakage rates, pressure compensating drip irrigation was required over an area of 500m2.  The planting of selected plant species was recommended over the effluent field to improve moisture evaporation.