What are rules in general as to the directing of rainspout or sump-pump water to my property from a house next door, even if their ground is slightly higher than mine?
It is a well-established legal rule that the owner of higher land has a right only to have surface water flow naturally from the high ground over the land of the lower property. So, when falling rain and melting snow flow naturally from upper land to lower land, the owner of the lower land has no right to erect embankments that change the natural flow of water.
On the other hand, the owner of upper land has no right to discharge water different from the usual and ordinary natural course of drainage, or to cause water to flow onto the lower land that would not have flowed there if the natural drainage conditions had not been altered. The upper-land owner cannot construct pipes or channels that discharge water onto the lower land.
These general rules are subject to the principal of "reasonableness." The owners of both properties must act reasonably to avoid unnatural accumulations or discharges of surface water on each other's property.
You may recover damages when an upper-land owner improperly causes surface water to drain onto your land. Such damages may include the cost of restoring land damaged by mud or debris from the increased flow of water from the higher ground. Damages for the loss of use of the land also may be recovered in a proper case. Where the damage is of a continuing nature, you may obtain a court-ordered injunction prohibiting your neighbor from continuing to direct surface water on your property.
Although the city may decline to intervene, the courts have full power to adjudicate your rights and to award appropriate relief in the form of money damages and an injunction.