V3 · Sonnet

Millponds turned into fields

What do you need to know before calling this place a pond?

The plan shows an ordinary field, schematic parcel boundaries G1 and G2, and one thin solid line: a candidate for a former mill dam. This is a guess from the lie of the land, not an established fact. Water appears only as a record from an old map, in a separate colour.

Own schematic – not a photograph and not a map of any specific place

Reveal and assess the record

±15 m

An assumption you enter: by how many metres the former shore could lie further away when the map is overlaid on today's field (0–40 m, in 5 m steps). Arrow keys, Home and End change the value.

Readout from the plan and profile

Uncertainty band
±15 m – band 30 m wide
Profile A–B: western shore
35–65 m from A
Profile A–B: dam trace
197–227 m from A
G1 (20 m from the outline)
5 m outside the band
G2 (30 m from the outline)
15 m outside the band

No parcel boundary falls within the ±15 m band. For any of them to be the former shore, the map record would have to be shifted by more than 15 m (the nearest is G1, 20 m from the outline). Changing the ± value changes the width of the uncertainty band, not the size or capacity of the pond – the schematic does not include it.

Without JavaScript you see the default state: record revealed, inaccuracy ±15 m.

  • Cultivated field and ditch (schematic). The green strip at the bottom is a grassy ditch.
  • Candidate for the dam: a guess from the lie of the land.
  • Pond record from an old map (model). Not a present-day observation.
  • Uncertainty band around the record: half the width = the assumed ± in metres, at the scale of the plan.
  • Profile A–B. Ring: the point where the profile crosses the dam candidate.
  • Boundaries of parcels G1 and G2. When they fall within the band, they turn brick-red.
Illustrative plan of a field with a dam candidate Own schematic: a field measuring 320 by 200 m in the model, a grassy ditch along the bottom edge, two parcel boundaries G1 and G2 and one thin line for the candidate former dam. Once the record from the old map is revealed, a blue dashed pond outline appears, with an uncertainty band around it and a red dashed line for profile A–B, which crosses the dam candidate. 50 m G1 G2 A B
Illustrative plan: own schematic, 320 × 200 m in the model. The horizontal scale is shared with the profile below (50 m bar). The legend explains the lines and bands.

Profile A–B across the dam (illustrative shape)

Illustrative profile A–B across the dam candidate Schematic without heights in metres: from point A the ground slopes gently down to the flat floor of the hollow, rises as an embankment with a flat crest and falls away behind it to point B. Once the map record is revealed, two blue bands show the stretches where the former shore could have lain: on the western slope and on the dam. G1 G2 A B 50 m
From A the ground slopes gently down to the flat floor of the hollow, rises as an embankment with a flat crest (the dam candidate) and falls away behind it. There is no checked profile, so we give no heights or vertical scale; this shape is illustrative only. The blue bands (once revealed) show where on the profile the shore from the map could have lain.

Three kinds of material, three different statuses

The field, the old map and the profile say different things. They overlap on one plan, but none replaces the others.

The field today

Present-day observation · on this page: no photograph of our own

Shows
The lie of the land, cultivation, a possible embankment, darker patches in the ploughed soil.
Does not prove
The age or function of an embankment. A hollow in ploughed soil does not prove a working water wheel.
Missing
A dated photograph of our own, taken from a legal vantage point.

The old map

Historical record · on this page: model outline

Shows
That at some point someone drew water here and, perhaps, a mill symbol.
Does not prove
Volume, a constant level or position to the metre. A parcel boundary need not be a former shore.
Missing
Two dated plans with a description of how they were overlaid on today's layout.

Profile across the dam

Height measurement · on this page: illustrative shape

Shows
Whether a transverse embankment closes off the hollow and what shape it has (if it were measured).
Does not prove
That water stood behind the embankment. An embankment can be a road, a field boundary or a drainage bank.
Missing
A levelling survey or elevation data with a date and a reference system. Without them we give no heights.

The three kinds of material converge only when their dates and reference system agree.

What can be said about the place?

Tick only what you have confirmed for a specific place. Unticked means ‘absent or not checked’, not ‘there was none’. The result is a statement about what may be claimed, not a score.

Ticked 0 of 4

No grounds

Nothing has been established yet. That does not mean there was no pond – only that there is no basis for calling it one.

  • No grounds: nothing established; this does not mean there was no pond.
  • Embankment alone: it may be a road, a field boundary or a drainage bank.
  • Map record alone: someone drew water; this fixes neither a shore nor a volume.
  • Document alone: an archival trace; the location remains to be established.
  • Sediments alone: origin undetermined.
  • Two grounds: partial convergence, still a hypothesis. Three or four: convergence of grounds, still a hypothesis requiring a source search.

How a pond stopped being a pond: typical causes, no dates

Typical causes of ponds disappearing, without a timeline. The order of steps 2–3 is undetermined: V2 gives the change of power source and the drainage and river regulation together, as occurring side by side, so they stand here under one number. There is no date for this place, so we draw none; an unknown date is neither zero nor the final stop.

  1. Impounding. An earth dam with a sluice closed off a small valley. The mill relied on the whole system: the basin, the dam, the headrace and a free outflow. date: none
  2. Change of power source, and drainage and river regulation – in parallel, order undetermined. According to the V2 description (to be checked in the source) both causes worked together:
    • Change of power source. Combustion-engine and electric drives reduced the need for water.
    • Drainage and river regulation. Draining land and regulating channels led to the removal of many small impoundments.
    for this place: date none · in general, per V2: 19th–20th century
  3. Ploughing the bed. The bed of the drained pond was absorbed into a larger field. The dam may be levelled or remain as a field boundary or road. date: none
  4. Today. What remains is a hollow, darker ploughed soil, an embankment or a ditch. Each trace on its own is ambiguous, which is why all three kinds of material are needed at once.

Explanation and limits

What is schematic

  • The plan and profile are our own drawing (a model). The dimensions of 320 × 200 m, the positions of G1 and G2 (20 m and 30 m from the outline) and the points on the profile (50 m and 212 m from A) are settings of the schematic, not measurements of any place.
  • The slider is an assumption you enter, not the result of georeferencing. It widens the band around the outline, in metres at the same scale as the plan, and the stretch of the profile where the shore could have lain. It does not change the size of the pond.
  • This page does not reconstruct capacity, does not recommend re-flooding fields, does not assess access to the land or flood risk, and does not identify any specific field.

What is missing compared with V2, and why

  • Fill-level slider 0–100%, water levels, freeboard, backwater extent and overflow warning: they suggested restoring a reservoir on invented numbers. Deliberately dropped.
  • A second profile C–D across the basin: without data it duplicated the first. Dropped.
  • A notebook in browser storage: not needed to understand the topic. Dropped, so the page saves nothing.
  • A verifier with four lists and scoring: replaced by four checkboxes and a statement about what may be claimed.
  • Kept from V2: the uncertainty buffer (0–40 m), the parcel boundaries layer, profile A–B, and caution about local place names and hollows in ploughed soil.

What is missing for a version based on real material

  • A photograph of our own of the field, taken from a legal vantage point.
  • Two dated plans with a description of the georeferencing.
  • A checked terrain profile (levelling survey or elevation data).
  • Verification of the sources in the section below: all were carried over from V2 without being reopened.

Sources

  • Academic source · Lower Vistula basin D. Brykała, Z. Podgórski, Evolution of landscapes influenced by watermills, Northern Poland, Landscape and Urban Planning 198 (2020), 103798. According to V2, the authors reconstructed the distribution of 1217 mills by combining cartography and historical sources.
    To be checked: the reference and the figure of 1217 were carried over from V2 and not opened when building this version. No URL in the input material.
  • Context photograph, not loaded Mill from Imielin in the Upper Silesian Ethnographic Park in Chorzów, photo by Jacek Durski: Wikimedia Commons, CC BY-SA 4.0. Context for the architecture, not the studied Lower Vistula pond; the photograph is not embedded, only linked.
    To be checked: authorship and licence per V2.
  • Own model The plan and profile on this page are V3's own schematics, with no basis in measurement. Dimensions and distances are model settings.