This includes management of water resources and provision of water supplies.
In the past the law relating to water management in Kenya was contained in the Water Act Cap 372 Laws of Kenya. In 2002 the Water Act was repealed and replaced by new law which is presently known as the Water Act 2002 and does not have a Chapter number. This came into effect in March 2003 by which Water Act Cap 372 was repealed.
Kenya’s statutory law on management of water resources is based on the common law and under the common law the land owner is presumed to own everything on the land upto the sky and down to the centre of the earth and this is a principle found in the course of property interest in land. At the same time the common law considers running water air and light to be things the property of which belongs to no person but the use to all persons. This principle is articulated in the case of Liggins V Inge 131 E.R 263.
Although the common law considers that the landowner owns everything on land a landowner has no property in running water air and light. What is land ownership gives him is a natural light to the use of running water air and light. The Natural light is considered to be incidental to the land ownership. The land owner whose land abuts on a water course is known as a riparian owner. A riparian owner is considered to have a natural right to water. With respect to riparian ownership the principle is articulated in Stockport Waterworks Corporation V. Potter 159 ER 545.
A right to water is the ability to exercise as of right the right which is available to all members of the public to use running water. None riparian owners can only exercise the right to use running water under an agreement with a riparian owner. An agreement providing for access over riparian land is known as an easement. In the absence of an easement non-riparian owner will be committing a trespass if he attempted to exercise the right to use running water. Because the right to use riparian water is shared by all riparian owners, its use must be reasonable. No one owner may use the water in a way which prejudices the right of other riparian owners. The principle of reasonable use is articulated in the case of Embrey v Owen 155 ER 579.
The extent of the riparian owners right to water and the scope of reasonable use can be reduced to 3 rights:
1. Right of Access and Navigation;
2. Right to the Natural quantity of the water in the water course;
3. Right to the Natural quality of the water in the water course;
These 3 are known as the riparian rights. The right to navigate the tidal river belongs to all members of the public ( a tidal river is a river that is influenced by the movement of the waves so typically a tidal river is salty River Tana in Kenya is a tidal river). The reason for the rights belonging to all members of the public is because the ownership of the land beneath a tidal river is vested in the State whereas the ownership of the land beneath a non-tidal river is vested in the riparian owner. The tidal part of the river is therefore accessible to any member of the public whereas the other part of the river is only accessible to the riparian owner. Only a riparian owner has a right of access to his land which enables him to embark and disembark on the non-tidal part of the river. This principle was established in the case of Lyon v Fishmongers Co.  1 A.C. 662 this is a case that arises out of fishing in the North Sea and the Fishmongers Company wanted a place on which to land after fishing but the particular sport on which they had established their key turned out to be non-tidal so the owner was denying them to embark or disembark on it.
The riparian owners right to quantity enables him to abstract, divert, obstruct or impound the water. The water abstracted may be used for ordinary domestic purposes such as drinking, cooking and washing or it may be used for purposes such as irrigation which the common law considers to be extraordinary purposes. Where the riparian owner uses the water for ordinary purposes, there is no restriction in the quantity that he/she may abstract even if the abstraction exhausts all the water in the river. This principle is articulated in the case of McCartney v Londondery & Lough Swilley Railway Co.  A.C. 301.
Where the riparian owner uses the water for extraordinary purposes, the use is restricted to the extent that it is subject to the right of other riparian owners. Any use which prejudices the use by a lower riparian owner is considered to be unreasonable. Basically is a riparian owner A is using the water for irrigation, if it prejudices the right of G to use water for ordinary purpose he is said to prejudice the use of water by G. This principle is articulated in the case of Swindon Waterworks Co. v Wilks & Berks Canal Navigation Co. [1875 7 LR 697.
Under the common law the riparian owner is not allowed to use riparian water for foreign purposes. Foreign purposes means use of water outside of the riparian land. Any such use is considered as unreasonable even if it does not prejudice the use of any other riparian owner.
The riparian owners right to quality entitles the riparian owner to the flow of water past his land in its natural state of purity and deteriorated by noxious matter discharged into it by others. This principle is articulated in the case of Jones v Llanwrst Urban District Council  1 Ch. D 393.
The principle of riparian ownership is the principle of water resources management which operated under the common law. under this the management of water resources was based on balancing the competing demands of neighbouring riparian owners.
As per the common law the riparian owner owns the land upto the midian line of the river but our statute specifically the Agriculture Act prohibits the riparian owner from cultivating up to 2 meters of the river. Under the Physical Planning Act the Local Authority can prohibit cultivation of the river beds.
The common law principles have however been incorporated into statute law even if with modifications and the current statute governing water resources management is the water Act Cap 2002 which was enacted in July 2002 and came into effect in March 2003. The Water Act 2002 provides for the management, conservation, use and control of water resources. Secondly it provides for the acquisition and regulation of rights to use water and for the regulation of water supply and sewerage services.
The Water Act has divided the management of the resource and the provision of the supply.