Littleton, CO Landscaping Rules: Rainwater Harvesting (2026)

The allowance sits in Table 10-1-3.4.2, Sustainable Development Practices, under the Water Conservation and Air and Water Quality Protection heading of Section 10-1-3.4, Sustainable Building Design. It is framed as a documented practice a single-family project can use toward the city's sustainability incentives, meaning a homeowner who installs qualifying rainwater equipment and shows it on construction drawings can count it toward the practice thresholds needed for a density bonus, height increase, lot coverage bump, parking reduction, sign area increase or open space reduction elsewhere in Table 10-1-3.4.1.

The permission is narrow by design: it applies specifically to single-family residential units, not multi-family or commercial buildings, and it caps storage at two containers per unit with a combined maximum of 110 gallons. The code ties the allowance explicitly to Colorado water law as amended, a nod to the state's history of tight restrictions on rainwater collection before the legislature relaxed them for small residential systems. A separate, larger-scale practice in the same table credits new buildings whose roofs are configured so at least 50 percent of the roof area is a green roof intended to capture and hold rainwater, which must also comply with the city's Storm Drainage Design and Technical Criteria Manual, showing the code treats small household rain barrels and large-scale green roof stormwater capture as two different tiers of the same water conservation goal.