Bach of the petitioners is the owner of an ancient and valuable mill-site with mill in operation on a stream in the town of Woodstock; on the same stream and above these the respondents are joint owners of two like mill-sites, with an idle mill upon one and none upon the other. Above these a branch empties into the main stream; upon this, forty years since, a dam was erected for the purpose of creating a reservoir for storage which continued in beneficial use to 1867. In that year the grantors of the respondents submerged it by the erection of a dam twenty rods below, at which point they were riparian proprietors on both sides. For about eight years thereafter they and their successors, including the respondents, drew the water stored by it in such quantities and at such times as were most bene*488ficial to all the mills, for the needs of all were substantially the same. But in 1875 the respondents, having lost one mill by fire, ceased to operate the other, and on several occasions thereafter under a claim of right detained water when it was essential to the operation of the petitioners’ mills, and on others allowed it to flow when it was not needed.
The petition seeks to restrain them from a repetition of these acts, and the case is reserved for the advice of this court.
Thirty years before the erection of the defendants’ dam, the branch for mill purposes practically ceased to be a running stream and became a reservoir for storage, from which water was drawn at such times and in such quantities only as would best supply the special and irregularly recurring-needs of mills, the detention and drawing- being by the consent and to the advantage of the proprietors of the old dam and of those of the mills below as well. As a matter of law, so far as the rights of all these are concerned, the artificial became by this long continued use the natural condition of the stream; to it thus changed they had adapted their respective mills as to construction, capacity and mofle of use; as an element of value in his privilege each had thus acquired a right to the use of this stored water in the reasonable, proper and customary manner and time of using it, having due regard to the rights of others to a like use; and this so long- as the proprietors of the dam should continue its existence for the purposes of storage merely. In 1867, therefore, the proprietors of the,old dam and reservoir had not the right to continue it in existence for storage and at their will to detain water therein or discharge it therefrom unnecessarily, unreasonably and to the injury of others; their power over it was held in strict subjection to this law of a reasonable and customary use as between themselves and other mill-owners below, which thirty years of such use had imposed upon them; and the proprietors of the new reservoir by submerging the old one practically took it to themselves and continued it in existence; but they took and continued it with all the limitations which this law had placed upon it.
*489Again, it is found that the respondents’ grantors submerged the old dam without contract permission from, or compensation to its owners, one of whom is a petitioner; that these knew of, but did not object to the erection of the new one, remaining silent because of their belief that it would be a substitute for and more beneficial than the old one; that during eight years the successive proprietors of the new one, including the respondents, observed the established law of a reasonable use of the water of the branch as a reservoir for storage, detaining and drawing it at times and in quantities most beneficial to all proprietors; and, that only since 1875 have they violated that law. The import of this finding is that in erecting the new dam the original proprietors thereof did not assert or exercise any rights in hostility to those of the proprietors of the old dam, but intended, and designed to be understood as intending, only to make them more beneficial than before. Thus taking the old reservoir to themselves and practically continuing its existence, they took it with all the limitations which this law of use had placed upon it. The silent consent thus received carried with it no permission either to detain or draw water unreasonably as against those who gave it; these last by giving have not barred themselves from a court of equity.
Therefore upon either ground they may maintain their petition.
And, when controversies arise between mill owners, each of whom has a separate right to the use of water to be drawn from a common reservoir for storage on irregularly recurring occasions of need, the time and manner depending upon the quantity in store, the needs of others and established custom, it is the proper office of a court of equity to call all of them into its presence, and in one proceeding and by one decree determine their respective rights and obligations. A separate action at law to each, for each wrongful detention or drawing, will not furnish adequate relief; practically, no relief at all-
The Superior Court is advised to command and enjoin the respondents, their servants, workmen, and agents, and all and every one of them, under a proper penalty that they do *490henceforth, so long as they maintain the new dam described in the petition, altogether and absolutely desist from drawing water thereby detained except for the supply of their mills; and if they Rave no occasion for drawing for such use, to desist from preventing or hindering the petitioners from drawing it for the supply of their mills in the reasonable and customary mode as to time and quantity. This order not to be construed as requiring the detention of water when the existence of the dam would be thereby put in peril.
In this opinion the other judges concurred.