No, Homeowners insurance is "Hazard Insurance" for losses to your home from the specified covered perils detailed in your policy. Covered perils are typically losses resulting from Fire, Lightning, Wind and Hail. Home insurance does not cover normal and expected maintenance or repair expenses that are considered incidental to home ownership. It's no different than a clogged drain for example, If it's not the result of a covered peril then it is not covered. Normal Maintenance, Repairs or Home Updates are not hazard losses.
does it cover well going dry
You can change insurance companies at any time you want to. Dry rot is not covered under any homeowners insurance policy and will not be covered by any other company that you change to. When the company finds that you are filing claims for such items and are mad because it wasn't covered the new application may be rejected as well by the new company. Dry rot is a maintenance issue and not the result of a covered cause under home insurance. To be covered by home insurance it must be the result of a covered cause which generally means it must be sudden and accidental.
This is due to evaporation. Wells get dry.
Very doubtful, the homeowners policy isn't a maintence policy, all losses must be sudden and accidental and a 'named' peril must have caused the loss. Additionally, this issue would probably be determined to be an "Act of God," thus placing the loss outside of insurance coverage.
No. But if any dental surgery is necessiated due to accident, the same will be covered under medical insurance purview.
Yes, a drought can cause wells to dry up if the level of the water table falls.
wells might go dry because the water table sometimes drops during very dry seasons.
build wells
It's so that the people living in those dry places have access to water.
Cold,dry climate with snow and ice cover
Ground water table to low underground stream dries up etc