The “tree dam” on the Mississippi River that people often refer to in casual conversation or forum posts is not the official name of any major structure ; it’s most likely a nickname or misremembered phrase for a standard lock and dam (like Ford Dam / Lock and Dam No. 1) or a local log/brush “wing dam” made of natural materials. Below is a quick, structured rundown to clear up the confusion and help you connect it to the real names used on maps and in news.

What you’re probably thinking of

When someone says “the tree dam on the Mississippi River,” they are almost always referring to one of these:

  • Ford Dam (Lock and Dam No. 1) in Minneapolis–St. Paul
    • Built on the Mississippi, sometimes called the “High Dam” in older sources.
    • Creates a reservoir that was once given the rather odd name “De Soto Harbor” behind it.
  • A wing dam or brush dam built with natural materials (trees, brush, logs) along the river to redirect flow, which locals might casually call a “tree dam.”

Because no big, officially recorded structure on the Mississippi is actually named “Tree Dam,” the phrase is almost certainly informal or descriptive, not an official project name.

Why “tree dam” sounds familiar

1. Natural-material river engineering

Historically, people have used logs, brush, and trees to build small, local dams or current-deflectors:

  • These could:
    • Protect banks from erosion.
    • Help form shallow areas and backwaters for habitat.
    • Influence navigation channels on a smaller scale.
  • In everyday speech, a pile of trees/logs across or along a channel easily becomes “that tree dam” even when it’s not a named structure.

Nothing in the major federal dam lists for the Mississippi shows “Tree Dam” as an official title; instead, you see numbered locks and dams (Lock & Dam 11, 14, 15, etc.).

2. Confusing “tree dam” with “Ford Dam”

In the Twin Cities area:

  • Ford Dam / Lock and Dam No. 1 sits on the Mississippi just upstream of Minnehaha Creek.
  • Older references call it the High Dam , and the reservoir above it was formally named De Soto Harbor in 1918.
  • If you’ve heard a story that involved:
    • A dam near trees and parkland
    • The Ford plant
    • Minnehaha Creek or riverfront parks
      …someone might have casually described it with a phrase like “that dam by all the trees,” which can easily morph in memory into “the tree dam.”

Official Mississippi River dams (what they’re actually called)

If you’re trying to match a vague memory to a real structure, here’s how the Mississippi dams are typically named:

  • Numbered locks and dams on the Upper Mississippi
    • Examples:
      • Lock and Dam No. 11 – General Zebulon Pike Lock and Dam near Dubuque, Iowa.
  * Lock and Dam 14, 15, etc., used to regulate navigation and water levels.
  • Headwaters dams in northern Minnesota
    • Built between 1884 and 1912 to control water levels at the river’s source areas.

None of these carry “tree” in the official name, but many are surrounded by forests, roots, and natural riverbank vegetation, which feeds into informal descriptions.

How to figure out which dam you meant

If you’re trying to pin down the specific place you remember, here’s a quick checklist:

  1. Location in your memory
    • Near Minneapolis/St. Paul → Likely Ford Dam / Lock and Dam No. 1.
 * Near Dubuque, Rock Island, Quincy, etc. → One of the numbered locks and dams (11, 14, 15, 21, etc.).
  1. What you remember doing there
    • Visiting a park, walking by Minnehaha Creek, seeing a large concrete structure above the falls → points to Ford Dam.
 * Boating and waiting inside a big “water elevator” with gates (a lock chamber) → any of the standard **lock and dam** sites.
  1. Visual memory
    • Massive concrete, steel gates, control structures = official lock and dam.
 * Piles of roots, driftwood, and trees naturally blocking a side channel or forming a snag = more of a **log jam** or improvised “tree dam,” not a named dam.

Mini story to anchor the idea

Imagine you’re standing on the Mississippi River near Minneapolis in the 1910s:

Workers have just finished a big concrete structure across the river—the High Dam—later called Ford Dam. Water backs up into a new reservoir that park officials decide to call De Soto Harbor. The steep banks are lined with cottonwoods and oaks, their roots grabbing the soil as the new waterline settles in. Local residents and visitors talk about “that dam by all the trees,” and over time, in casual retellings, someone remembers it as “that tree dam on the Mississippi.”

Your memory or a forum conversation may have preserved that informal wording, even though the official name is Ford Dam / Lock and Dam No. 1 and the reservoir is De Soto Harbor.

Latest discussions and “trending” context

Online, you mainly see:

  • Discussions of Mississippi River locks and dams , climate impacts, navigation, and aging infrastructure.
  • Occasional posts sharing photos of weathered tree roots and floodplain trees along the river and its tributaries, which visually fit the idea of a “tree dam” but aren’t official dam structures.

So the phrase “tree dam” shows up in casual, descriptive talk or image captions, not in formal engineering or government documentation.

Quick recap (TL;DR)

  • There is no major, officially recorded dam on the Mississippi River literally named “Tree Dam.”
  • The phrase most likely refers informally to:
    • Ford Dam / Lock and Dam No. 1 (sometimes called High Dam), with its reservoir named De Soto Harbor , or
    • A local wing dam / log jam made of trees and brush.
  • If you remember a big concrete dam near parkland and trees in the Twin Cities area, the closest match is Ford Dam (Lock and Dam No. 1).

If you can share more about where along the Mississippi you saw or heard about this “tree dam” (near which city or landmark), I can help you narrow it down to the most probable specific lock and dam.