Re: 1/2 of Yard always wet and soggy
Unless your surrounding neighbors are experiencing similar problems, it is highly unlikely that you're getting run off from that distance affecting your yard.
What is more probable is that your yard is lower than surrounding yards and/or neighbors have diverted run off from their properties to yours (illegal ). Most standing water problems can be handled simply by regrading the soil to slope away from the house in all directions and crowning the yard at roughly the centerline so that water sluffs to the sides, where you would then either use grading or install drain lines to carry the excess water out to municipal systems.
Your problem could be exacerbated by a high water table, not uncommon during winter months. A drain system will definitely help to rid your yard of excess moisture.
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