Light pollution's effects #3:

Light Trespass

If your neighbor's lawn sprinkler sprayed water all over the side of your house, or stayed on all night long, you'd complain about it, right? So why should night lighting that spills onto your property be any different?

When poorly shielded fixtures cast light far beyond the property lines, the result is light trespass. Often it's caused by backyard floodlight designed to cover the widest possible area. Or it might be from a business in the neighborhood that keeps its security lights on all night long.

Light trespass is both annoying and wasteful. Sometimes the solution is easy: angling the fixture downward or attaching a simple shield often puts all those stray lumens in their proper place. But sometimes it's more complicated, especially if the offending neighbor or business is obsessed with security — or a streetlight outside your bedroom window.

Fortunately, more and more municipalities are enacting regulations to control outdoor lighting, and in these statutes light trespass is typically prohibited. So check NELPAG's listings to see if your town has an outdoor-lighting ordinance. Even if it doesn't, you can always bring light-trespass situations to the attention of your local Planning Board, Building Inspector, or Public Works Department.

Effect #4 . . .