Stephen Kenny's overhaul of the Lilywhites continues apace with the acquisition of former Celtic player and capture of current midfielder's signature
New manager Stephen Kenny beat off stiff competition to secure the signing of Ireland under-21 international Towell, who knows McDonnell well after rooming together during their youth-team days at Celtic.
Dundalk chairman Ciaran Bond told the club's official website: "We had to overcome a lot of competition to seal Richie's signing for the club. We are delighted that Stephen was able to sell Dundalk FC to Richie and that he will be with us next season."
Meanwhile, Pat Fenlon is set to add Bohemians' Evan McMillan to his Hibernian ranks as the defender undergoes a medical, as well as a trial match, this week in Edinburgh.