Expressing bad consequences: dreadful; dismal.
Warning of bad consequences: ill-boding; portentous.
Bad in quality, awful, terrible.
Requiring action to prevent bad consequences: urgent, pressing.
Causing ruin; destructive, calamitous
Characterized by ruin; ruined; dilapidated; as, an edifice, bridge, or wall in a ruinous state.
Extremely costly; so expensive as to cause financial ruin.