We are of opinion that the exceptions in this case are well taken, and that the case must be sent to a new trial. The declaration alleges that there is and always has been a small stream of water running through the centre of the plaintiff’s land, and that the defendants by their negligent .and wrongful acts have suffered the outlet or culvert through which the water of this stream had been accustomed to flow to be stopped up; whereby the plaintiff's land was injured. The gist of the action, therefore, was the obstruction of this alleged stream or watercourse. By the statement of the evidence offered at the trial, it appears that the existence of this stream or watercourse was in contention between the parties. That it was incumbent on the plaintiff to prove the fact, cannot be doubted. Unless he did so, there would be a fatal variance between his declaration and proof. Ashley v. Wolcott, 11 Cush. 192. In this state of the case, the defendants were clearly entitled to an instruction in substance similar to one for which they asked, which was, that the jury must be satisfied that there was a stream of water running through the plaintiff’s lot described in the writ, or some part thereof, and that it must be a permanent stream of water, and not that which is accumulated by *22rains 01; the melting of snows, or by artificial underdraining of the plaintiff’s land. The refusal of this instruction was erroneous, because it left the case without any definite or distinct rule to enable the jury to distinguish between a stream or watercourse and a mere occasional flow of water over the surface. Luther v. Winnisimmet Co. 9 Cush. 171.
Nor was this the only error. The instructions given to the jury in effect authorized them to find a verdict for the plaintiff, although no stream or watercourse, in the legal sense of those words, was proved to have existed in the plaintiff’s land. No action can be maintained for changing the course or obstructing the flow of mere surface water by erections on adjoining land. Parks v. Newburyport, 10 Gray, 28. Flagg v. Worcester, 13 Gray, 601. It makes no difference in the application of this rule that land is naturally wet and swampy. A conterminous proprietor may change the situation or surface of his land by raising or filling it to a higher grade, by the construction of dikes, the erection of structures or by other improvements which cause water to accumulate from natural causes on adjacent land and prevent it from passing off over the surface. Such consequences are the necessary result of the lawful appropriation of land, whatever may be its nature, and, although they may cause detriment or loss to others, it is damnum absque injuria, and affords no ground of action. Nor can a party gain a right to the flow of surface water over his neighbor’s land by collecting it in drains or culverts or artificial channels, unless he maintains them for a length of time sufficient to acquire a right or easement by adverse user. He cannot by hisown act merely, without the assent or acquiescence of the adjoining owner, change their relative rights and duties, and convert a flow of surface water into a stream, with all the legal incidents of a natural watercourse. These principles were not stated to the jury with fulness and accuracy, nor were the instructions such as to lead the jury to an intelligent application of the law to the facts in proof. Exceptions sustained.