Renwick, of Vulcan Close, was detained and officers began to search the U-bend of the toilet.
When nothing was found, they turned their attention to an external waste pipe and followed it to a grid outside the property.
The officer opened the grid and found what they believed to be heroin and cocaine.
Further examination revealed that there was 120 wraps of cocaine and 121 wraps of heroin with a street value of £2,410.
A taser, phone and quantity of cash were also discovered during the raid.
Liverpool Crown Court
Renwick, who has a history of drug offences, was subsequently arrested and charged with possession with intent to supply class A drugs and possession of a taser.