在本世纪末之前，北荷兰的N.V.PWN供水公司将在其所有处理厂安装软化装置。由于化学软化，钠含量将超过规定。因此，普华永道决定安装反渗透（RO）进行海水淡化，并将其作为一种新的地表水直接处理的核心。采用了超滤和反渗透的组合，在不使用化学氧化的情况下进行脱盐、去除微污染物和消毒。

Before the end of this century, the N.V. PWN Water Supply Company of North Holland will have installed softening in all of its treatment plants. As a result of chemical softening, the sodium content will exceed guidelines. PWN has therefore decided to install reverse osmosis (RO) for desalination and to make this RO the core of a new direct treatment of surface water. A combination of ultra filtration and reverse osmosis has been adopted, providing desalination, removal of micro pollutants, and disinfection without the use of chemical oxidation.