Sika waterproof mortars and mortar admixtures for rigid waterproofing lining in potable water tanks have excellent technical properties to seal against damp soil, seepage and percolating water. These materals are applied on prepared, internal concrete surfaces by manual application, or by spray to provide excellent solutions for complicated detailings. The post applied waterproofing mortar is used in combination with joint sealing products. Applied Sika waterproofing mortar linings have long lasting service life.