This park, built as a replacement for some of the parkland lost in the construction of the new Yankee Stadium, is located just across the street from the Gateway Center, and, like Gateway, sits on land once occupied by the Bronx Terminal Market.
The name of the park refers to the mill pond that once existed on the Harlem River, created by Robert Macomb in 1814 as a reservoir for his gristmill. He built a dam across the river, topped by a toll bridge, at the location where the white truss bridge in the background (named, appropriately, the Macombs Dam Bridge) currently spans the Harlem. In authorizing the dam, the state legislature required that it be navigable by boats, and a small lock was built for this purpose. Macomb, however, made no effort to maintain the lock, and the river was soon rendered impassable. The dam changed hands a few years later, but the new owners did nothing to restore the river's navigability.
The citizens of the area were furious about the blockage of the Harlem, and in 1838, after consulting with legal experts, they devised a plan to remedy the situation. The leader of the group, Lewis G. Morris, chartered a coal ship from New Jersey to make a delivery to his property north of the dam, knowing, of course, that such a trip would be impossible. When the ship arrived at the dam, the captain requested that the draw be opened so that he could continue on his way. The bridgekeeper informed him that there was no draw to open and that the vessel would be unable to pass.
At this point, Morris, along with dozens of local men, emerged from the shadows where they had gathered and proceeded to tear a hole in the dam large enough to accommodate the ship. The owners of the dam filed a suit against Morris, but he came out victorious when the courts agreed with him that the dam constituted a "public nuisance" in its obstruction of the river. This 1900 NY Times article provides a very colorful account of the whole affair.
Off in the distance, you can see our favorite set of quadruplets. And, in case you were wondering, the structure that looks like a boardwalk running along the water is actually a single-track rail line called the Oak Point Link.
Thanks for the link, that was another interesting read.