Want of definiteness is the earmark of surface water. At times it may be considerable in extent.19 It may even tend to flow in a definite direction.20 But it is irregular in flow and has no definite, natural channel. It may become a watercourse, however, at some definite point. Thus, in Nealley v. Bradford," the master found that what was mere surface water beyond the limits of the highway became a natural watercourse within the limits of the highway. In a word, it is want of regularity and definiteness which distinguishes flow of surface water from a watercourse.

A natural watercourse has been described as a natural easement appurtenant to the soil. Each riparian proprietor has a right that it flow to him substantially as it was wont to flow. The proprietor above may not divert it from the proprietor below; the proprietor below may not back it up upon the proprietor above. It is true that each riparian proprietor is entitled to use the water to some extent upon his tract. But for the purposes of this article, the precise nature and extent of this right to use need not be considered. Here it is sufficient to say that each riparian proprietor is entitled to the stream ut currere solebat.22

The right of the riparian proprietor to the stream as it was wont to flow does not yield to the highway easement. The public authorities have no inherent right to stop natural watercourses to the damage of riparian owners. Of course the rights of riparian owners are subject to the exercise of eminent domain,23 just as other property rights are subject thereto. But even when a way is laid out across a natural watercourse, by an authority possessing the power of eminent domain, the rights of riparian owners must be considered. Thus, where a corporation was authorized to lay out a road over a natural watercourse, it was intimated that pro

19 Dickinson v. Worcester, 7 Allen 19 (1863); Cassidy v. Old Colony R. R. Co., 141 Mass. 174, 5 N. E. 142 (1886).

20 Parks v. Newburyport, 10 Gray 28 (1857); Dickinson v. Worcester, 7 Allen 19 (1863); Gannon v. Hargadon, 10 Allen 106 (1865); Cassidy v. Old Colony R. R. Co., 141 Mass. 174, 5 N. E. 142 (1886); Middlesex Co. v. McCue, 149 Mass. 103, 21 N. E. 230 (1889); Collins v. Waltham, 151 Mass. 196, 24 N. E. 327 (1890). 21 145 Mass. 561, 14 N. E. 652 (1888).

22 Merrifield v. Lombard, 13 Allen 16 (1866).

23 Boston Belting Co. v. Boston, 152 Mass. 307, 25 N. E. 613 (1890); Boston Belting Co. v. Boston, 183 Mass. 254, 67 N. E. 428 (1903); Rowe v. Granite Bridge Corp., 21 Pick. 344 (1838); Moulton v. Newburyport Water Co., 137 Mass. 163 (1884).

vision must be made for the watercourse or else damages paid.24 And it has been held that a town is liable for permitting a third party to close the openings in a highway bridge built over a tidal stream, whereby the water was set back upon plaintiff's land.25

But while the bridge must be adequate to provide for conditions naturally to be anticipated, the city is not liable in tort because the bridge was insufficient for an extraordinary freshet.26 Yet, where the bridge was negligently built in a manner insufficient to take care of the stream under ordinary conditions, tort will lie, even though the bridge was built under proper authority, since such authority must be reasonably and skillfully exercised.27 On the other hand, the city is not liable because a bridge originally sufficient becomes insufficient to take care of the natural flow of the stream because of the unauthorized acts of third parties.28 In bridging natural watercourses, then, the authorities are liable in tort if the bridge be insufficient for conditions naturally to be anticipated, but are not liable for damage due to extraordinary freshets or to the unauthorized acts of third parties.

Culverts are subject to very similar rules. The culvert need only be adequate for the flow of the stream in its natural state.30 Thus, a city is not liable because a culvert, originally sufficient, becomes insufficient by reason of subsequent alterations in the stream made by the county commissioners.30 On the other hand, the city must construct and maintain a culvert sufficient for the natural flow of the stream.31 Thus, tort will lie for failure by the city to use reasonable care to keep the culvert clear, even though the plaintiff owns the land on both sides of the street and the fee of the street.32 The rule is thus declared by Bigelow, J., in Parker v. Lowell (p. 357): 33

24 Rowe v. Granite Bridge Corp., 21 Pick. 344 (1838).

25 Lawrence v. Fairhaven, 5 Gray 110 (1855).

197 Mass. 568, 83 N. E. 893 (1908).

26 Sprague v. Worcester, 13 Gray 193 (1859).

27 Perry v. Worcester, 6 Gray 544 (1856).

28 Wheeler v. Worcester, 10 Allen 591 (1865).

See also Stimson v. Brookline,

30 Cochrane v. Malden, 152 Mass. 365, 25 N. E. 620 (1890). See also R. L., c. 48,

§ 57, and STAT. 1906, c. 463, § 101.

31 Parker v. Lowell, 11 Gray 353 (1858); Stanchfield v. Newton, 142 Mass. 110, 7 N. E. 703 (1886).

32 Parker v. Lowell, 11 Gray 353 (1858).

33

11 Gray 353. The language is evidently borrowed from Chief Justice Shaw in

"It is now the well settled rule of law in this commonwealth that in all cases where a highway, turnpike, bridge, town way or other way is laid across a natural stream of water, it is the duty of those who use such franchise or privilege to make provision by open bridges, culverts or other means for the free current of the water, so that it shall not be obstructed and pent up to flow back on lands belonging to the riparian proprietors. And it is their duty not only to make such bridge, culvert or passage for water, but to keep it in such condition that it shall not obstruct the stream."

Yet natural watercourses and riparian rights may be made to yield to the public interest. Thus, equity will not enjoin a bridge corporation which possesses the right of eminent domain from diverting a natural watercourse into an artificial canal if such a change be reasonably necessary.34 The riparian owner is left to his remedy in damages under the statute for any acts lawfully done in the exercise of the powers conferred.35 But where the damage is inflicted unnecessarily 36 or negligently 37 in the exercise of such powers, tort will lie. It has, however, been held that, where the acts were beyond the scope of the powers conferred and not merely an improper exercise of those powers, no action lay against the town, 38 apparently upon the theory that the acts were the acts of the officers, individually, rather than of the public authority. Authority may be given, therefore, to alter natural watercourses

Lawrence v. Fairhaven, 5 Gray 110, 116, (1855). The same rule has been applied to railroads. Estabrooks v. Peterborough, etc., R. R. Co., 12 Cush. 224 (1853); Blood v. Nashua, etc., R. R. Co., 2 Gray 137 (1854); Mellen v. Western Railroad Corp., 4 Gray 301 (1855).

34 Rowe v. Granite Bridge Corp., 21 Pick. 344 (1838).

35 Rowe v. Granite Bridge Corp., 21 Pick. 344 (1838) (semble); Hull v. Westfield, 133 Mass. 433 (1882); Boston Belting Co. v. Boston, 149 Mass. 44, 20 N. E. 320 (1889); 152 Mass. 307, 25 N. E. 613 (1890); 183 Mass. 254, 67 N. E. 428 (1903); Holleran v. Boston, 176 Mass. 75, 57 N. E. 220 (1900).

36 Curtis v. Eastern R. R. Co., 14 Allen 55 (1867), 98 Mass. 428 (1868).

37 Boston Belting Co. v. Boston, 149 Mass. 44, 20 N. E. 320 (1889); 183 Mass. 254, 67 N. E. 428 (1903); Lawrence v. Fairhaven, 5 Gray 110 (1855); Perry v. Worcester, 6 Gray 544 (1856); Morse v. Worcester, 139 Mass. 389, 2 N. E. 694 (1885). See also Estabrooks v. Peterborough, etc. R. R. Co., 12 Cush. 224 (1853); Mellen v. Western R. R. Corp., 4 Gray 301 (1855). But if the damage be caused in the exercise of the police power by a city acting in a governmental capacity, no action lies. Harrington v. Worcester, 186 Mass. 594, 72 N. E. 326 (1904).

38 Anthony v. Adams, 1 Metc. 284 (1840); Tyler v. Revere, 183 Mass. 98, 66 N. E. 597 (1903).

for public purposes 39 with liability for damages under the statute for acts lawfully done in the exercise of such authority and a further liability in tort for damage unnecessarily or negligently caused by misuse of such powers.

An upper riparian proprietor has no right to pollute the waters of a natural watercourse so as to render them unfit for lawful riparian uses by a lower riparian proprietor.40 But in Jackman v. Arlington Mills 40 it was held that he may collect water into a channel and discharge it into a natural watercouse if he does not unduly increase the stream or pollute it. Yet, if he thereby creates a nuisance as to the lower proprietor, tort for nuisance will lie.41 The lower proprietor may also maintain a bill in equity to prevent invasion of his riparian right, though equity may decline to interfere if no material damage is done and no prescriptive right can be gained.43 A private riparian owner, then, is not permitted to pollute a natural watercourse to any material extent.

The rights of the public are harder to determine because they are complicated by questions of procedure. The legislature may authorize the taking of or injury to riparian rights with corresponding rights of compensation under the statute.44 In such a case the acts authorized by the statute cease to be wrongful, and neither a bill in equity nor action of tort 46 will lie therefor

45

39 Beals v. Brookline, 174 Mass. 1, 54 N. E. 339 (1899), and n. 23.

40 Harris v. Mackintosh, 133 Mass. 228 (1882); Parker v. American Woolen Co., 195 Mass. 591, 81 N. E. 466 (1907); Merrifield v. Lombard, 13 Allen 16 (1866); McNamara v. Taft, 196 Mass. 597, 83 N. E. 310 (1907); Dwight Printing Co. v. Boston, 122 Mass. 583 (1877); Jackman v. Arlington Mills, 137 Mass. 277 (1884). 41 McGenness v. Adriatic Mills, 116 Mass. 177 (1874).

42 Harris v. Mackintosh, 133 Mass. 228 (1882); Parker v. American Woolen Co., 195 Mass. 591, 81 N. E. 466 (1907); Merrifield v. Lombard, 13 Allen 16 (1866); McNamara v. Taft, 196 Mass. 597, 83 N. E. 310 (1907).

43 Brookline v. Mackintosh, 133 Mass. 215 (1882).

44 Washburn & Moen Co. v. Worcester, 116 Mass. 458 (1875); Rowe v. Granite Bridge Corp., 21 Pick. 344 (1838); Moulton v. Newburyport Water Co., 137 Mass. 163 (1884); Boston Belting Co. v. Boston, 149 Mass. 44, 20 N. E. 320 (1889); 152 Mass. 307, 25 N. E. 613 (1890); 183 Mass. 254, 67 N. E. 428 (1903).

45 Rowe v. Granite Bridge Corp., 21 Pick. 344 (1838); Washburn & Moen Co. v. Worcester, 116 Mass. 458 (1875).

46 Perry v. Worcester, 6 Gray 544, 547 (1856) (semble); Flagg v. Worcester, 13 Gray 601 (1859); Emery v. Lowell, 104 Mass. 13, 16 (1870); Hull v. Westfield, 113 Mass. 433 (1882); Boston Belting Co. v. Boston, 149 Mass. 44, 20 N. E. 320 (1889); Bainard v. Newton, 154 Mass. 255, 27 N. E. 995 (1891); Holleran v. Boston, 176 Mass. 75, 57 N. E. 220 (1900).

so long as damage is not negligently caused thereby. Moreover, this is true even though the acts, if unauthorized by statute, would be tortious.47 The statute in effect takes away the remedy at common law by action of tort and substitutes therefor the statutory remedy.48 But this renders the statutory remedy exclusive. Consequently the failure of the plaintiff to maintain his action of tort is no indication at all that a common-law right has not been invaded. Such an action may fail either because the injury to the plaintiff is damnum absque injuria or because he has mistaken his remedy.

On the other hand, recovery by petition under the statute does not necessarily indicate invasion of a common-law right. The statute may give recovery for injury even where no common-law right is invaded. Thus, the building of a subway in the highway is not an invasion of the common-law right of the abutter.49 Yet the subway statute has been held to give damages for an act which would impose no liability at common law.50 A similar liberal construction has been placed upon the grade-crossing act,51 upon the highway statute,52 and upon the act which provided for improving Stony Brook,53 to cite merely two or three examples. Of course the question must depend on the construction of the particular statute involved. But there is a tendency on the part of the court to construe such statutes as in pari materia one with the other, upon the ground that they are part of a general scheme of legislation.54 Hence success under the statute does not indicate the existence of a common-law right any more than failure in tort

47 Hull v. Westfield, 133 Mass. 433 (1882); Washburn & Moen Co. v. Worcester, 116 Mass. 458 (1875).

48 Perry v. Worcester, 6 Gray 544, 547 (1856) (semble); Boston Belting Co. v. Boston, 149 Mass. 44, 20 N. E. 320 (1889); Holleran v. Boston, 176 Mass. 75, 57 N. E. 220 (1900). But cf. Westcott v. Boston, 186 Mass. 540, 72 N. E. 89 (1905).

49 Sears v. Crocker, 184 Mass. 586, 69 N. E. 327 (1904).

50 Fifty Associates v. Boston, 201 Mass. 585, 88 N. E. 427 (1909).

51 Hyde v. Fall River, 189 Mass. 439, 75 N. E. 953 (1905), overruling Rand v. Boston, 164 Mass. 354, 41 N. E. 484 (1895).

52 Marsden v. Cambridge, 114 Mass. 490 (1874); Woodbury v. Beverly, 153 Mass. 245, 26 N. E. 851 (1891).

53 Boston Belting Co. v. Boston, 152 Mass. 307, 25 N. E. 613 (1890); 183 Mass. 254, 67 N. E. 428 (1903).

54 Hyde v. Fall River, 189 Mass. 439, 75 N. E. 953 (1905); Fifty Associates v. Boston, 201 Mass. 585, 88 N. E. 427 (1909).