More than 300 charges are expected against 84 street-level drug traffickers operating in the city's Lowertown area, following a five month investigation by Ottawa police.

Police arrested 20 individuals in round-ups on Tuesday; 22 others were already in custody. Police say warrants will be issued for the remaining suspects.

Police concentrated their efforts in the Byward Market, due to its high level of pedestrian traffic, restaurants, bars, tourist attractions and businesses.

Project Woody, which began in January, led to the seizure of $68,000 in illicit drugs and $9,500 in cash.

Police say a pink tinge was added to some of the drugs known as "pink crack." Investigators believe the colour was added to the crack as a marketing ploy.

Police also arrested four people that were not identified as part of the project, including one individual who was carrying 300 ecstasy pills and one ounce of marijuana. The suspect's vehicle was also seized.

The goal of the project was to diminish the supply of drugs on downtown streets and to encourage referrals to addiction support agencies.

Police say the dealers are of various ages, race, gender and socio-economic status. Those arrested will appear in court on Wednesday.

Project Woody is the third time the street crime unit has swept Ottawa streets in an 18-month period. The unit is designed to combat street-level drugs, particularly in the downtown core.