I would check the water pump... Mine was making a rather interesting sound like that, turned out that one of the bolts on the pump pulley had worked it's self lose somehow... I imagine it was because I put to much anti-seize on it... Could be the water pump all together, I believe they are prone to failure on these cars???
2000 Ford Focus US Spec Zetec 5 speed "Blue Dragon"
2000 Renault Clio 1.4 DOHC 5speed "Snap Dragon"
Hatch Nation #32