The 22 year-old man was arrested after the drugs were found in a house at Foyle Springs.
The PSNI also carried out a follow-up operation at a property in Creggan yesterday.
A 42 year-old man arrested during the Creggan operation has been released on police bail pending further enquiries.
The 22 year-old man has been charged with possession of a Class A controlled drug, possessing a Class A controlled drug with intent to supply and being concerned in the supply of Class A controlled drug.
He is expected to appear before Magherafelt Magistrates Court this morning.