The plaintiffs allege that as a result of the overflow of a town river and pond they sustained bodily injury and property damage. A judge of the Superior Court, sitting without a jury, found for the town on all counts of the plaintiffs’ amended complaint. Of the several counts in the plaintiffs’ complaint only those alleging negligence and private nuisance are being pressed on this appeal from the ensuing *507 judgment. 2 We reach a Solomonic conclusion: the negligence claim was correctly decided by the trial judge; the nuisance claim was not. 3
Since 1973, the plaintiffs, Donald and Dorothy Tarzia, have been resident owners of property located near the Weir River in Hingham and Foundry Pond, which is owned by the town of Hingham. On the northerly side of the pond is a dam with control gates and sluices. In 1982, the river overflowed and flooded the plaintiffs’ property. The plaintiffs implored the town to take measures to prevent future flooding; however, the town took no action, although remedial action was contemplated by an agency of the town. On June 2, 1984, the river again overflowed and flooded the plaintiffs’ property. On that occasion the. flooding persisted for two to three days, causing severe damage to the plaintiffs’ real estate and personal property.
The trial judge made the following findings. “The flooding of the plaintiffs’ property was caused by: (1) a buildup of silt and vegetation in the Weir River which decreased its water-carrying capacity; (2) a buildup of silt and vegetation in Foundry Pond which diminished its capacity to retain water within its banks, and the failure to maintain any drainage structures in an operational mode.” Road sand and salt contribute to the problem in the river. Prior to 1971, the municipal entity responsible for the river and the pond had drained the pond and removed silt from the river, and on several subsequent occasions it had formulated various plans to dredge the pond, install control gates to control the seasonal water flow, and implement long range maintenance programs for the river.
*508 After concluding that the town “was aware of the situation for many years and took no remedial action” in furtherance of any of those plans, the judge determined that the plaintiffs could not recover for negligence as the decision how best to manage the silt and weeds in the river and pond fell within the discretionary function exception to the Massachusetts Tort Claims Act. 4 He further determined that the town’s conduct in maintaining the river and pond was reasonable and, therefore, did not constitute a nuisance.
In the circumstances presented here we conclude that the town’s failure to remove the accumulated silt and vegetation in the pond and the river does not constitute actionable negligence. In
Whitney
v.
Worcester,
Citing
Doherty
v.
Belmont,
The second prong of the plaintiffs’ argument on appeal is that the trial judge erred in finding that the town’s conduct in maintaining the river and pond was reasonable and, therefore, did not create a nuisance. A private nuisance is actionable when a property owner “creates, permits, or maintains a condition ... on [its] property that causes a substantial and
*510
unreasonable interference with the use and enjoyment of the property of another.”
Asiala
v.
Fitchburg,
The plaintiffs argue that the facts of the instant case are analogous to those in Schleissner v. Provincetown, supra, and thus its reasoning should be controlling here. We agree. 7 In Schleissner, the court upheld the trial court’s finding of nuisance against a municipality where (1) its storm water disposal system caused the flooding of the plaintiff’s property; (2) the town had been aware of the periodic flooding of the plaintiff’s property for years; (3) the town took no remedial action; (4) the intrusion to the plaintiff was not de minimis; and (5) an expert testified that the town could eliminate the flooding of the plaintiff’s property by removing two drainage pipes installed by the town. 8
In the present case, in concluding that the town had acted reasonably and that the plaintiffs’ claim of nuisance failed, the judge applied the legal criteria that he thought applicable *511 to natural conditions of land as opposed to artificial conditions on land. 9 That he did this is evident from his explanation:
“There is no dispute that a natural silt and vegetation buildup caused the flooding .... The only similar case of the natural filling of a watercourse resulted in a finding of no nuisance. Sawyer v. Shader,321 Mass. 725 (1947)q The cases relied on by the plaintiffs involve some affirmative action by the defendant to create or maintain the condition complained of as a nuisance.”
The traditional common law rules distinguished between the legal criteria that apply to natural conditions as compared to artificial conditions. See Restatement (Second) of Torts §§ 839, 840(1) (1977). Prosser & Keeton, Torts § 57 (5th ed. 1984). But even assuming that the common law rules are still applicable, and we do not decide that they are, “[t]he term ‘natural condition’ of land [is narrowly defined and] means a condition that is not in any way the result of human activity .... [A]n artificial structure that was harmless when created but that has become dangerous through natural decay is not a natural condition.” Restatement (Second) of Torts § 840 comment a.
Here the pond whose overflow clearly contributed to the flooding of the plaintiffs’ land was artificially dammed at its northerly side and had control gates and sluices.
10
The town’s
*512
land was not in its natural condition. Thus, even if the rule apparently relied upon by the judge were applicable, the rationale of
Schleissner
v.
Provincetown,
We thus conclude that the judge’s determination that there was no nuisance was based at least in part on his misapplication of the law. 13 In view of his other findings, we consider it likely that, applying the correct rule, that of Schleiss-ner, he would find that a nuisance exists. See notes 7 & 8, supra. In any event, the question must be decided anew. Accordingly, the judgment is reversed as to the count alleging nuisance and is otherwise affirmed. The case is remanded to *513 the Superior Court for such further proceedings as are consistent with this opinion.
So ordered.
Notes
The issues presented on appeal are whether the trial judge erred in finding that (a) the town’s failure to take remedial action to prevent damage to the plaintiffs’ property was protected by the discretionary function exception to G. L. c. 258, § 10(6), and (b) the town’s conduct in maintaining its property was reasonable, thereby defeating the plaintiffs’ nuisance claim.
The law of nuisance is an “impenetrable jungle.” Prosser & Keeton, Torts § 86 (5th ed. 1984). Moreover, we realize that “[i]t is difficult, if not impossible, to describe nuisance without reliance on concepts . . . [of] negligence.” Nolan & Sartorio, Tort Law § 446, at 190 (2d ed. 1983).
The discretionary function exception exempts public employers from liability under the Massachusetts Tort Claim Act for claims based on “the exercise or performance or the failure to exercise or perform a discretionary function or duty on the part of a public employer or public employee, acting within the scope of his oEce or employment, whether or not the discretion involved is abused.” G. L. c. 258, § 10(6), as inserted by St. 1978, c. 512, § 15.
In
Doherty,
the Supreme Judicial Court held that “[a]ny negligence in performing, or failing to perform, the ministerial task of maintenance does not rise to the level of ‘public policy or planning’ decisions warranting protections under G. L. c. 258, § 10(6).”
Id.
at 276. See
Sanker
v.
Orleans,
The plaintiffs, relying on
Cady
v.
Plymouth-Carver Regional Sch. Dist.,
The
Schleissner
court, relying on
Triangle Center, Inc.
v.
Department of Pub. Works,
In the instant case (1) the accumulated silt and vegetation in the river and pond caused the flooding of the plaintiffs’ property; (2) the town had been aware of the flooding of the plaintiffs’ property for years; (3) the town took no remedial action; (4) the intrusion was not de minimis; and (5) an expert testified that the town could eliminate or substantially reduce the flooding by clearing the pond and river of silt and debris and could also do so by using the control gates.
It may be that the judge also afforded the town protection because of the policy making nature of any decision to remedy the situation. The judge stated that the “issue of discretionary function appears again in a different context .... There were a number of considerations, financial, practical and ecological which entered into the decision process. The court is not prepared to hold as a matter of law that any decision made on the maintenance of these waterways was unreasonable.”
The judge, as earlier stated, found that the flooding was caused in part by a buildup of silt and vegetation in the river and the pond and also by the failure to maintain drainage structures in an operational mode. In
Sawyer
v.
Shader,
The buildup was also partly (although not quantifiable by the judge) a result of the town’s sanding and salting of the local streets.
That section, entitled “Possessor Who Fails to Abate Artificial Condition,” provides in relevant part:
“A possessor of land is subject to liability for a nuisance caused while he is in possession by an abatable artificial condition on the land, if the nuisance is otherwise actionable, and
“(c) he had failed after a reasonable opportunity to take reasonable steps to abate the condition or to protect the affected persons against it.”
The plaintiffs argue that, even if this court should think that the reasoning of
Schleissner
is not controlling here, there is another line of cases that has application to the instant circumstances. See, e.g.,
Kurtigian
v.
Worcester,
