Oregon Revised Statutes Water Resources: Irrigation, Drainage, Flood Control, Reclamation § 540.220

(1) A watermaster may appoint an assistant to take charge of the ditch, pipeline or reservoir involved in a distribution or division of water under ORS 540.210. The assistant watermaster shall be paid by the water users from the ditch, pipeline or reservoir for the cost of the distribution. The Water Resources Commission may require the water users to pay in advance the estimated compensation and expenses of the assistant involved in the distribution or division of the water.

(2) In the case of partnership ditches, pipelines or mutual irrigation corporations organized for the benefit of the members or stockholders, the expense of the assistant shall be paid by the water users in proportion to the area of land for which each water user is entitled to the use of water from the ditch, pipeline or reservoir, so that each shall pay the same rate per acre.

(3) In the case of ditches, pipelines and reservoirs constructed and operated for sale or rental of water, the wages and expense of the assistant shall be paid by the owner of the ditch, pipeline or reservoir, unless otherwise provided in written contracts with water users using water from the ditches, pipelines and reservoirs involved in the distribution or division of water.