New legislation aimed a creating a framework for managing water resources is expected to be approved in principle.
The Scottish Government's so-called hydro nation policy is set out in the Water Resources (Scotland) Bill, which proposes to legislate for a broad range of areas relating to water and sewerage services.
The Bill includes plans to extend Scottish Water's functions along with proposals to to enable the making of water shortage orders and to protect the public sewerage network from harm.
The proposed legislation has already been backed by a Holyrood committee and this afternoon MSPs as expected to endorse its general principles.
Members of the Scottish Parliament's Infrastructure and Capital Investment Committee have already scrutinised the Bill.
When they published their report on the matter earlier this month, convener Maureen Watt said: "It is in everyone's interests that our valuable water resources and assets are both protected and utilised appropriately.
"The committee agrees with the proposals set out in the Bill, which seek to allow for water and sewerage services to be enhanced and improved, and which have the potential to bring benefits to customers."