It is hereby declared and agreed that the insurance by this policy is extended to cover the legal liability of the Insured for personal injury, smoke, disease, loss or damage caused by or through or in connection with water pollution, fumes to persons or property when it proved to have been  caused by immediate accidental discharge due to defective drains, sewers or sanitary arrangements. However :

• The Insurer shall not be liable for any such loss or damage insofar in such loss or damage is covered by any liability insurance
• The liability of the Insurer under this clause in respect of any such loss or damage to property shall not in any case exceed the limit of liability specified in the Policy subject to otherwise to the terms, conditions and exclusion of the Policy