Spanish term (edited): escuálido

There is some confusion in your question, the answer seems to be provided by tou: squalid is a correct translation of escuálido in this context, where it justt means dirty

squal£id
Pronunciation:*skw*l*d also -w*l- sometimes -w*l-
Function:adjective
Inflected Form:sometimes -er/-est
Etymology:Latin squalidus * more at SQUALOR

1 a : marked by filthiness and degradation usually from neglect *exchanged T squalid and savage dress for a suit of Dutch cloth— Francis Parkman* *ramshackle frame houses T notorious firetraps of squalid appearance— American Guide Series: New York City* *ministering every year to T the poorest, the sickest, the squalidest human beings— Saturday Review* *rickety tables T surmounted by T squalid overflowing ashtrays— John Wain* *rueful squalid poverty that crawled by every wayside— John Morley* b : RUN-DOWN, SHABBY *life at a fashionably squalid preparatory school— New Yorker*
2 obsolete a : DRY b : SHAGGY
3 a : morally debased or repulsive : CONTEMPTIBLE, SORDID *a sublime prophet T or a squalid quack— La Selle Gilman* *a series of rather squalid little affairs that everybody knew about and nobody mentioned— Ngaio Marsh* b : lacking refinement or sophistication : CRUDE *finds Voltaire's summary of ancient philosophy squalid— J.H.Seyppel* *such imagination as he can detect is usually commonplace or squalid— Bernard De Voto*
4 : marked by an unwholesome appearance *his complexion sallow and squalid— E.G.Bulwer-Lytton*
synonyms see DIRTY

...or deteriorating

given the context...

See my reference posting for links - there is very little left of this temple, and what is remaining is all in ruins.