Well Water & Groundwater Rules in Fillmore County, NE

This site's Fillmore County hub flagged a genuine open question: whether the Little Blue Natural Resources District's newly mandatory groundwater-allocation area, Hydrogeologic Unit 2, actually reaches into Fillmore County. It does. The district's own hydrogeologic materials place southern Fillmore County -- along with northern Thayer County -- inside Unit 2, which means a five-year mandatory allocation is now a real, current constraint for irrigated land in part of this county.

This page covers what's specific to Fillmore County. For the general explanation, see the national guide.

The open question, resolved: southern Fillmore County is inside Hydrogeologic Unit 2

Fillmore County is served by two Natural Resources Districts -- the Upper Big Blue NRD to the north and the Little Blue NRD, which the district's own hydrogeologic study materials subdivide internally into numbered management units based on aquifer characteristics. Hydrogeologic Unit 2, specifically, is described in the district's own materials as covering southern Fillmore County together with northern Thayer County, with an estimated groundwater storage volume of roughly 332,000 acre-feet. That confirms a fact this site's hub could not previously verify: the Little Blue NRD's mandatory allocation entered for Unit 2 is not a development happening only elsewhere in the district's seven-county service area -- it reaches into Fillmore County itself, in the southern part of the county nearer the Thayer County line.

The mandatory allocation itself took effect for the district's 2025 crop year and runs for an initial five-year period, set at 65 acre-inches of groundwater per certified irrigated acre within Unit 2, with the district citing persistently low aquifer groundwater levels as the reason for imposing it. An acre-inch is a specific, measurable unit -- roughly 27,150 gallons applied across one acre -- and 65 acre-inches over five years works out to an average of 13 acre-inches per year, a real constraint on irrigation scheduling for row crops in dry years compared to unrestricted pumping. The district's own materials indicate penalties apply for exceeding the allocation within the covered period, though this research did not confirm the specific penalty structure or whether any carryover or banking provisions exist between years.

What to check before buying irrigated land in southern Fillmore County

If you're evaluating irrigated cropland anywhere in Fillmore County, the first question to answer is not what the district's allocation rule says in the abstract, but whether the specific parcel actually falls inside Hydrogeologic Unit 2's boundary -- land just across an internal line, still within Little Blue NRD's broader territory but outside Unit 2, would not be subject to this particular mandatory allocation, while land under the neighboring Upper Big Blue NRD to the north of the county is a different district entirely with its own separate rules. Ask the Little Blue NRD directly for the parcel's certified-irrigated-acre status and its exact position relative to the Unit 2 boundary, since NRD-drawn management-unit lines don't always align with visually obvious landmarks or road grids.

If the parcel is confirmed to sit inside Unit 2, ask the district for the specific field's pumping and allocation history if available -- a previous owner's actual usage pattern against the 65-acre-inch, five-year cap tells you far more about real-world irrigation flexibility than the raw allocation number alone, particularly if the prior owner's cropping pattern differs from what you intend to plant. Also ask specifically whether small-capacity domestic or livestock wells on the property are exempt from the Unit 2 allocation, since Nebraska NRDs commonly exempt wells below a certain pumping capacity from irrigation-allocation rules generally, though this research did not confirm that exemption's specific terms for Little Blue NRD's Unit 2 in particular -- treat it as a question to ask directly rather than an assumption to rely on.

Well Water and Groundwater Rules in Fillmore County, Nebraska

The open question, resolved: southern Fillmore County is inside Hydrogeologic Unit 2

What to check before buying irrigated land in southern Fillmore County

Ready to talk to someone who knows land?