CPV code 45252100 designates Sewage-treatment plant construction work in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
45252100 sits under 45252000 (Construction works for sewage treatment plants, purification plants and refuse incineration plants) and groups 5 more specific sub-codes. When classifying a tender, choose the narrowest code that still covers the full subject of the contract.