My name is XXXXX XXXXX I'd be happy to answer your questions today. I'm sorry to hear that this happened.
If he actually sprayed your mother with a power soaker, that's battery. She could sue him for damages. Battery is any harmful or offensive touching. If he either directed it intentionally at her or intentionally used it knowing that she would likely get wet as a result, she can bring a claim against him in Small Claims
If this happens again, you can call the police tor report it immediately. Technically, directing a power washer into your yard is a trespass. If there is any damage to your property as a result, you could also bring suit requiring him to pay to repair the damage. Because trespass is an intentional tort
, the judge could also order him to pay nominal damages if there was no physical damage, but that's usually $1 or so. That may not be enough to dissuade him from behaving in this manner in the future.
If the trucks are coming and going at times early in the morning or late at night and waking you, that could constitute a private nuisance. A private nuisance claim could be brought in the district court
, rather than the small claims division, and you may be able to get a judge to order him to park the truck elsewhere (especially since it's a zoning violation to park it there). If he violates the judge's order, he could be fined or jailed for contempt of court.
There unfortunately isn't any way to force the town to investigate. The only thing you can do is continue to create a record, including making sure that pictures show the license plate or any other identifying information in addition to the address or front of the house, so it's clear where the truck is parked.
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