Is the Club Dorada Palace the big 4 star hotel on the main road into Salou from Reus (Calle Ciudad de Reus)? That's in a mainly residential there is an internet cafe just down the road from there not that far from a road called St Augustin?
If so, then when we went in February (we stayed at the Jardines Paraisol apartments just up the road) there was some building going on behind there - we could see it from our apartment but it wasn't particularly intrusive in anyway although I couldn't say what it would be like from your hotel. I don't recall it actually being on the hotel itself (apart from them replacing paving stones) seem to think it was a new development going up behind that whole area.
Hope this helps.
Wendy
PS I have a photograph that I took towards the pool at our apartments that may show the building work in the background pm me if you want me to have a look and if it does I can always email it you.