Timber Damage Assessment (TDA) is the compensation owed to the Alberta Government and/or any Forest Management Agreement (FMA) holder on Crown forested lands that are no longer available for forestry use, due to a disposition (such as a wellsite, road, pipeline, powerline, etc.).
The Government of Alberta publishes the tables used in the process for determining the amount of TDA assessed for a given disposition.  Information on the process and the current TDA tables can be found on the Alberta Government TDA Webpage.