1. The board shall not permit the water in any reservoir constructed under the provisions of title 21 of this article to rise above the high flow line thereof, except during floods or other emergencies, and if during floods or other emergencies the water shall rise above such high flow line the board shall immediately open the outlet gates in such reservoir and take such other action as may be necessary to lower the water to the high flow line of such reservoir with the least practicable delay. The board shall keep an accurate and, so far as practicable, continuous record of the height of water in each reservoir and shall install and maintain at suitable places such gauges or instruments as may be necessary therefor.

2. Except for absolutely necessary inspection or repairs, no reservoir shall at any time be drawn off below the low flow line, or to such extent as to expose isolated pools which may cause unsanitary conditions, unless due provision is made for draining such pools into the lowest water level of such reservoir. It shall be unlawful for any officer or person in charge of any reservoir to neglect the provisions of this section.

3. It shall be unlawful for any person to open or close or cause to be opened or closed a gate or gates in any dam constructed pursuant to the provisions of this title without the consent of the board or for any person to interfere in any way with the operation of, or injure a regulating reservoir.

4. When the flow of a river at any water power plant thereon falls below the average normal flow thereof, the then natural flow of the river at a reservoir dam thereon shall not be restricted without the consent of the owner of such power plant.

5. No regulating reservoir shall be constructed pursuant to the provisions of title 21 of this article of a capacity greater than is required to maintain the average flow.

6. The expense of maintenance and operation of any existing reservoirs shall be paid as now provided by law until such reservoirs are taken over by the board pursuant to the provisions of title 21 of this article, and thereafter such expense shall be paid as herein provided for the maintenance and operation of reservoirs constructed pursuant to title 21 of this article.