Va. Code § 62.1-122
If, on the report, or on other evidence, it appears to the court that by granting such leave the mansion house of any person other than the applicant himself, or the outhouses, yard, garden, or orchards thereto belonging, will be overflowed or taken, or that the health of the neighbor will be annoyed, the leave shall not be granted. But if it shall not so appear, the court shall then grant or refuse the leave, as may seem to it proper. If it be granted, the court shall lay the applicant under such terms and conditions as shall seem to it right. It shall, in particular, provide, that ordinary navigation and the passage of fish shall not be obstructed, nor the convenient crossing of the watercourse impeded; and where, under such leave, an existing mill, manufactory, machine, or engine is to be supplied with water by a canal, the court shall prescribe a time within which the dam, whereby water had before been supplied, shall be abated, which time shall not be more than one year from the completion of the canal. Whenever such leave is granted, the tenant of any land through which any canal may be cut, may cross it with such fencing, and bridges, and erect such water gates as he may from time to time deem necessary, not obstructing the passage of the water to the mill, manufactory, machine, or engine.
Va. Code § 62.1-122