The DNR's design and the City of Longville's own survey put the crest of the Girl Lake outlet within an inch of each other. So the question for owners on Child, Girl and Woman lakes is no longer whether the new rock arch rapids was built to the right height. It is whether water is leaving the chain through a handful of lower gaps beside that crest, and how much.
That shift happened in September. It explains why the conversation now runs on surveyed elevations, records requests and a second engineering review, and less on photos of exposed shoreline.
The 1.7 feet that set a normal year
On a dock, people judge lake level by the stain line on a boulder or the old high-water mark on shore. The DNR measures it against two fixed elevations, and the space between them is smaller than most owners expect.
| Elevation | NGVD 29 | NAVD 88 | What it means |
|---|---|---|---|
| Ordinary High Water Level, Girl and Woman | 1323.6 ft | 1324.3 ft | Upper limit of normal long-term fluctuation; the boundary of public waters |
| Natural runout, Girl Lake outlet | 1321.9 ft | 1322.6 ft | The elevation where water starts to leave the lake |
The OHWL was set by Commissioner's Order in 1955 after a public hearing held by the DNR and the Boy River Chain of Lakes Association. The runout elevation was set by DNR survey staff in 1978 and confirmed by a new survey in 2023.
The two are 1.7 feet apart. The DNR's September fact sheet says the OHWL is not a lake-level management goal or target. A lake can sit below its OHWL and still be above the runout, still sending water down the Boy River.
When the whole range between "water stops leaving" and "top of normal" is about 20 inches, a few inches at the outlet is a large share of it. The datums matter too. The DNR notes that LakeFinder's historical records use NGVD 29 while the project surveys use NAVD 88, and the two differ by 0.7 feet at Girl Lake. Mixing them up produces a false gap of more than eight inches.
Where the City's surveyor and the DNR agree
The structure in question replaced the old Girl Lake outlet dam in November 2025. Cass Soil and Water Conservation District sponsored and built it, and the DNR designed and permitted it. Cass County's 2025 project report describes a seven-tier rock arch rapids that reconnects 54 miles of the Boy River for fish passage.
According to the DNR, the project was meant to keep the established runout and its pre-project hydraulic performance. It was not meant to raise or lower the lake. The design puts the bottom of the low-flow notch at 1322.6 feet NAVD 88, the runout elevation.
On September 21, Northeast Technical Services surveyed the outlet for the City of Longville and measured a center crest of 1322.54 feet NAVD 88. That is 0.06 feet, under an inch, from the DNR's design figure. On the central notch, the two sides' numbers match.
The low points beside the notch
The disagreement is in the same survey. The City reported elevations next to and downstream of the crest between 1321.63 and 1322.03 feet NAVD 88. In its September 22 letter to the DNR, the City described these as flowing paths roughly 10 to 11 inches below the nominal crest.
The DNR's fact sheet takes up the same concern. The low-flow notch is an intentional design feature that concentrates low flows for fish. The DNR says the notch is not nine inches below runout, as some communications had suggested, and that flow should stop once the lake reaches runout, "absent other pathways for water movement." The City's survey is an attempt to document exactly those other pathways. That leaves a live question about how the measured low points affect the outlet's performance.
Flow data has not settled it yet. At a September 2 public meeting, Jeff Davis of the Woman Lake Action Group presented a hydrologist's August 19 snapshot. It showed outlet flow at roughly three times measured inflow, on the order of 2 million gallons per day. The DNR responds that one discharge measurement cannot establish why a lake level changed. A full water balance would need repeated, concurrent measurements that account for weather, groundwater, wetland storage and other flows. The flow measurement planned for the September 21 survey was canceled because velocities varied too much, and it is being redone with narrower measurement steps.
What the drought accounts for, and what it leaves open
The DNR points first to the sky. North-central Minnesota has received 12 to 16 inches less precipitation than normal over the past four years. The agency calls the result a "storage drought," with wetlands, streams, soil moisture and groundwater all drawn down. It says recovery would take months of precipitation far above normal. The Pine Cone Press-Citizen reported in May that Cass County had 2.07 inches of precipitation from January through March 2026. That was 0.67 inches below normal and the driest such stretch since 1985. The same article reported Ten Mile Lake, which isn't on the Girl Lake outlet at all, at a record low.
The Woman Lake Action Group acknowledges the drought but argues it doesn't rule out a separate effect from the structure. Its September presentation said a 135-year analysis of five-year averages found similar or drier periods about 40 percent of the time. In August, the group compared recent changes in lake level. From July 1 through August 11, Girl dropped 5.52 inches, Woman 4.8 and Child 5.76. The same update reported that nearby Inguadona Lake rose 5.28 inches over a longer span, April 23 to August 10.
The before-and-after photos have their own complication. The DNR says a beaver dam was blocking the old outlet before construction and holding water above natural runout. In its view, pictures of little or no flow below the old structure are not a like-for-like comparison. The Action Group said it had found no records showing the old dam needed repair.
What it looks like from shore
The most recent DNR lake-level readings reported for the three lakes are early-season figures from May 6, 2026: Girl Lake at 1322.95 feet, Woman at 1323.02 and Child at 1322.35. DNR lake-level records use the NGVD 29 datum. The City's September 21 outlet survey recorded surface water just upstream of the rock arch rapids at 1323.15 feet, but that figure is in NAVD 88 and comes from the outlet itself, so it doesn't line up directly with the May readings. The Pine Cone Press-Citizen reported that put Child about an inch above its record low and Woman about nine inches above its record low. The May figures are not October levels. The summer declines described above came after them.
By late summer the effects were showing up on docks. Lakeland PBS reported in August that some owners had added dock sections and were struggling to get boats on and off lifts. A Woman Lake resort owner said the low water threatened safe use of a harbor that holds about 55 boats. Longville's August resolution described Girl Lake as at its lowest recorded level in about 91 years. The resolution also states explicitly that it makes no finding about the cause.
Where it stands this week
Everything has moved quickly since mid-August:
- August 19. Jeff Davis told the Longville City Council that a petition had 838 signatures and that he had paid for an independent study. The council, led by Mayor Jocko Kline, passed Resolution No. 2026-819 asking the DNR Commissioner for an independent engineering and hydrologic review.
- September 2. At a public meeting, the Woman Lake Action Group reported more than 1,100 signatures. In a letter that day, Commissioner Sarah Strommen said the DNR remained confident in the design and offered to work with the City on the scope, reviewer and cost-sharing for a review.
- September 22. After the Phase I survey, the City asked the DNR for temporary, reversible measures to stop discharge through the low points. It said it was not asking for a new lake level or a permanent redesign at that stage.
- September 28. The DNR replied that it was reviewing the City's survey and running its own technical review, including field checks of flow and lake elevation. It said it was still deciding whether interim action was warranted. It also noted the City had started its own independent review and asked to see the scope.
- October 1. The DNR delivered 26 records to the City in response to its data request, including historic surveys, construction reports and permits. As of October 2, the City was still checking them against the request.
A joint DNR and City outlet inspection was planned for September 30. As of October 4, no account of what it found and no DNR decision on interim flow limits has been published. No consultant or timeline for the City's Phase II review has been announced either. Longville's council meets on the third Wednesday of each month, so the next regular meeting is October 21. The DNR's letter also names the Child, Girl, Woman Lakes Area Association and Cass SWCD among the groups it wants involved as the review goes forward.
Questions about shoreline, frontage or dock depth on a Woman Lake Chain property right now mostly depend on which elevation, and which datum, someone is measuring against. If you'd like to talk through what this season's water levels mean for a property you own or are thinking of selling, Sandy Smith and our team can go over it with you in person. Schedule a Free Consultation.
This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.
