The provisions of the conveyance from the Souhegan Manufacturing Company to Putnam and Chase expressly *Page 397 gave to the latter the right to draw from the grantor's pond, through the flume belonging to the premises conveyed, all the water not needed for the grantor's use; that is, Putnam and Chase took by the conveyance the right to draw and to use so much of the water in the pond as was not required by the company in operating their mill as it was then operated. The plaintiff has succeeded to the rights of Putnam and Chase, and the defendant to those remaining in the company. The plaintiff is therefore entitled to the surplus water not needed for the defendant's use. Necessity being the test of the defendant's right, it is not for him to complain that the plaintiff's surplus was increased by the burning of the company's mill in 1872. Whenever he requires such increase for any useful purpose he may take it, upon the familiar principle that where a right exists to use a certain quantity of water, a change in the mode or object of the use without increasing the quantity is no violation of the right; but until then he plainly has no right to raise his gates and cause the water for which he has no use to run to waste. Having done so, and to the plaintiff's injury, he is liable to respond to her in damages in this proceeding. The assessment made at the trial term is accordingly affirmed.
The evidence excepted to was admissible. The acts and conduct of the parties thus shown did not alter or vary the terms of the conveyance in any respect. Their only effect was to define and limit the water rights of each as they understood them to exist under the conveyance. This they might properly do, and certainly there can be no more weighty evidence in the interpretation of that conveyance, so far as it relates to water rights, than the practical construction given to it by the parties themselves, as evidenced by the manner of their use of such rights.
The temporary injunction heretofore granted is made perpetual. If, however, in point of fact the storage capacity of the pond or the water-supply of the river has been increased by the defendant or his grantor since the conveyance to Putnam and Chase, to the extent of that increase the injunction will be modified upon application. Whittier v. Cocheco Mf'g Co., 9 N.H. 454.
Decree for the plaintiff.
CLARK, J., did not sit: the others concurred.