Loudoun County, VA Landscaping Rules: Rainwater Harvesting (2026)
Key Facts
- Scope
- Applies only inside the Limestone Overlay District
- Rule
- Groundwater-fed irrigation systems prohibited
- Acceptable sources
- Cisterns, stormwater management ponds
- Excluded source
- Community well water also disqualified
- Reviewer
- Dept. of Building and Development
- Authority
- Zoning Ordinance § 5.05; Va. Code Title 15.2 Ch. 22
Summary
Inside Loudoun County's Limestone Overlay District, Zoning Ordinance § 5.05.F.I bans irrigation systems fed by groundwater. Builders and homeowners in the mapped karst terrain must draw irrigation water from a source that doesn't depend on groundwater, cisterns and stormwater management ponds are named examples, and even community well water is expressly disqualified as an acceptable source.
Irrigation Systems. Irrigation systems are prohibited unless the water for such system is supplied from a source that is not dependent on groundwater, such as, but not limited to, cisterns and stormwater management ponds. Community water supply systems that obtain water through community wells are not an acceptable source of water for irrigation systems.
Full Breakdown
The Limestone Overlay District (LOD) covers land in Loudoun County underlain by limestone bedrock and Karst terrain, sinkholes, swallets, and underground solution channels where groundwater contamination and land subsidence are real risks. 05's stated purpose is to protect groundwater and surface water resources from contamination and reduce subsidence risk, drawing authority from Va. 1 (state water control). F sets 'Development Standards for the LOD,' and subsection I addresses irrigation directly: any irrigation system on Covered Activity land in the LOD is prohibited unless its water source is not dependent on groundwater.
The ordinance names cisterns and stormwater management ponds, both forms of rainwater harvesting and capture, as acceptable sources, and it goes further than most local water rules by expressly disqualifying community water systems that rely on community wells, closing a loophole that might otherwise let a shared well stand in for a private one. I at all, the analysis always starts with whether the parcel falls inside the LOD.
Violations & Fines
Section 5.05 is enforced through the development review process rather than after-the-fact citations: site plans, subdivision plats, and building permits proposing a groundwater-fed irrigation system inside the LOD are rejected by the Department of Building and Development until the applicant substitutes an approved non-groundwater source. Deeds and plats must also carry the required LOD notice language under § 5.05.F.K, and the Zoning Administrator is the designated contact for compliance questions.
Frequently Asked Questions
Does the irrigation rule apply to my whole Loudoun County lot?
Can I use a private well to run my irrigation system?
Does a shared community well satisfy the rule?
What water sources are acceptable for irrigation in the LOD?
Sources & Official References
Other rules in Loudoun County
Compare Loudoun County to another location·View the Virginia landscaping rules overview
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