Career
Colahan created the "Sirena" fountain for the Italian town of Bordighera. His sculpture of the head of Victor Smorgon was bought by the National Gallery of Victoria. His work can be found in the collections of the State galleries of Melbourne, Adelaide and Brisbane.
He was appointed an Australian official war artist in 1942.
A portrait in oil of F. Matthias Alexander (of "Alexander technique" fame), painted by Colahan to commemorate the subject"s 80th birthday, was shown on the British Broadcasting Corporation"s Antiques Roadshow programme in May 2013, when it was still in the possession of the son of the wife of Alexander"s nephew.