Noblesville, IN Fence Regulations: Retaining Walls (2026)

Noblesville's Unified Development Ordinance treats a low retaining wall as a minor improvement and a tall one as a reviewed structure. Section 159.121(C)(2)(e) exempts "retaining walls forty-seven (47) inches or less in height" from the section's accessory-structure setback requirements entirely, alongside fences, drainage installations, boathouses, seawalls, and handicap ramps. Once a wall reaches "forty-eight (48) inches in height or more," division (D)(14) applies a full set of standards: the wall may be tiered or terraced as long as the area between tiers stays pervious and uncovered by impervious material; height is measured from natural grade at the base of the wall, or from the highest point's natural grade if the height varies; the wall must not block or dam an existing swale or drainage path; it must be built of brick, rock, or textured or patterned concrete or other masonry that complements the site; and it should be set back from the property line by a distance equal to its own height.

Division (D)(14)(g) caps every retaining wall in the city at eight feet, no matter the district, and (D)(14)(h) requires the applicant to submit engineering on the structure "as deemed necessary by the Building Commissioner," meaning taller or more complex walls can be required to carry a stamped engineering design before the Planning and Development Department signs off.