741. Traffic being what it is, it is lamentable that our roads are unable to take the load.
unpardonable : (of a fault or offence) too severe to be pardoned; unforgivable.
deplorable : shockingly bad in quality.
inexcusable : too bad to be justified or tolerated.
terrible : extremely bad or serious.
lamentable : (of an event, action, or attitude) unfortunate; regrettable.
Synonym of lamentable is deplorable