| Thornapple River | |
|---|---|
USGS Satellite Image |
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| Origin | E of Thornapple Lake |
| Mouth | Grand River Ada |
| Basin countries | United States |
| Length | 88 miles (142 km) |
| Mouth elevation | 617 feet (188 m)[1] |
| Avg. discharge | 1000-1500 ft³/s at mouth[2] |
The Thornapple River is an 88.1-mile-long (141.8 km)[3] tributary of Michigan's longest river, the Grand River. The Thornapple is located in western Michigan. It joins the Grand in Ada, Michigan.
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The Thornapple, one of the Grand's major tributaries, is about 88 miles (142 km) long. It has headwaters in Eaton County and flows through Barry County before entering the Grand River in Kent County. The Grand flows to Lake Michigan, and the Thornapple watershed/drainage basin is a part of that larger watershed/drainage basin system. The Thornapple is described as "An easygoing stream that meanders through low southwest Michigan woodlands."[4] The Thornapple itself has a major tributary in the Coldwater River.[5] The Thornapple is the only major Grand tributary to join the lower Grand from the south.[6]
The major rivers and drainages of the Grand River drainage basin were formed during the Pleistocene epoch and the subsequent advance/retreat glaciation cycle, terminating about 6–8000 years ago.[7] Prior to European settlement, the Thornapple drainage basin had mixed hardwood/conifer forest and barrens.[8] and was home to the Ottawa and Potawatomi Native Americans.[9] who called it the Tomba-Signe (or "river with the forked stream")[10]
During the early settlement of Michigan, Rix Robinson, the first permanent settler of Kent County, established a fur trading post in conjunction with John Jacob Astor's American Fur Company, at the mouth of the Thornapple in 1821 to trade with the Potawottomi and conduct other business. By 1837, with the fur trade in decline, Robinson facilitated a treaty between local tribes and the Federal government that opened much of the area, including the Thornapple basin, to white settlement.[11]
As with many rivers in 19th and early 20th century America, the Thornapple had significant logging, milling, and manufacturing activity along it. As an example:
The river was subject to periodic flooding. The 1904-1905 flood was "the worst flooding in Ada history."[13] A number of dams were constructed in the early 20th century for flood control and power generation.
In 1957, as part of a M-21 Grand River bridge replacement project, the mouth of the Thornapple and lower channel were relocated about 500 feet upstream on the Grand, and land that had been the site of Robinson's first home in Ada and trading post was inundated.[14]
Today the Thornapple is not a navigable waterway, and there is no commercial water transport on it. The major use of the river is recreational. The Thornapple River sees significant use for rafting, kayaking and canoeing on a small but significant portion of its 88-mile (142 km) extent. The Thornapple supports several canoe livery businesses.[15]
From the headwaters in Eaton County to Thornapple Lake, the river is creeklike, with narrow banks and tangled undergrowth restricting easy passage. The lower stretch of the river is a series of dam-created reservoirs that are heavily developed. However from the lake to the first dam impoundment below Irving, is a 14-mile (23 km) stretch of river that is suitable for family outings and float trips.
The river is also very fishable. A large number of species inhabit the river, among them: sunfishes (largemouth bass, smallmouth bass, rock bass bluegill, crappie, pumpkinseed, and warmouth), bowfin, brown bullhead, minnows (common carp, chub, dace, and shiner), suckers (white sucker and redhorse), perches (yellow perch, walleye, darter), brook stickleback, northern pike, longnose gar trouts (brown trout, brook trout, and rainbow trout), and lampreys (American brook lamprey and chestnut lamprey).[16]
The river is claimed to be "nationally known as a fine smallmouth bass stream", and there are typically large numbers of small mouth bass in the free-flowing sections between Nashville and the junction with the Coldwater river.[6] Fishing access is good, as most of the free-flowing Thornapple can be waded or floated during normal summer flows, and many county road crossings afford good access.
In addition to the many fish species that live in the Thornapple, the river is also home to other wildlife including osprey, bald eagles, herons, and various species of ducks, some who winter in Michigan.[17] People use the recreational facilities on the river to observe these species for pleasure and knowledge seeking.
On the lower reaches of the river, especially in the several impoundments behind the dams, there is significant recreational watercraft usage,[18] both powered and sail, as well as personal water craft, although no provisions for specific clearances under bridges have been made, and the dams do not have locks, so portaging or trailered transport is required to move craft from one reach to another.
The river is crossed by many county and state roads, as well as I-96 and several railway lines. A notable crossing is one of nine remaining covered bridges in Michigan, the Ada Covered Bridge, which spans the Thornapple in Ada.
No specific clearance provision is required, as the river is not navigable and is broken into sections by the dams and low bridges.
The river has at least five dams.[19] In stream flow order from headwaters to the mouth, the major dams are:
| Location | Description/Notes | Coordinates | Mean Elevation of Impoundment[20] |
Google Maps Link |
Image |
|---|---|---|---|---|---|
| Nashville | Closest to the headwaters. A very small elevation change dam that does not generate power, only serves to control flow. Some may consider it more of a weir, although it is signed as a dam. The dam was removed in September 2009 to improve fish habitat.[21][22] | 813 ft | [1] | ||
| Irving | Downstream from Thornapple Lake (natural lake). Actually 3 different dams, a power dam at the west end of a power canal, and two flow control (one obsolete and unused, the other more recent) dams to the east. This topographic map from USGS (via Microsoft Research Maps) should clarify. See also this image from TIGER data. Operated by Commonwealth Power Company.[23] | 741 ft | [2] | ||
| Middleville | Operated by Commonwealth Power Company.[23] and located in the village of Middleville. | 724 ft | [3] | see CPC images | |
| Labarge (Caledonia) | Near 84th street crossing. Operated by Commonwealth Power. | 692 ft | [4] | ||
| Cascade | Near the Grand Rapids airport. Generates 1.4 Mw of electric power. Owned by Cascade Township and operated under contract by STS Hydropower Ltd.[24] A picture is on Flickr. | 665 ft | [5] | ||
| Ada | Just upstream from the Ada Covered Bridge, less than 1 mi from the mouth. Generates 1.6 Mw of electric power. Owned by the Thornapple Association and operated under contract by STS Hydropower Ltd, (DBA Ada Cogeneration Limited Partnership)[25] | 632 ft | [6] |
The lowermost dam in Ada (known as the Ada Dam) is owned by an association of about 230 homeowners who have property on the river between the Cascade and Ada dams. Formerly a power dam, built in 1926 by the Water Power Company, and, from 1934 on, owned and operated by Consumers Power, it was sold to the Thornapple Association for $1 in 1969 so they would maintain it for flood control after Consumers discontinued electricity generation as uneconomical in 1968. The association operated the dam for flood and water control, funding operations with a special tax levy.
However, in the late 1970s, the association, using a study grant from the United States Department of Energy, did a feasibility study on re-electrification. In 1983 the power generation capability was restored by STS Hydropower, who operates the dam under long term contract, and the association now generates substantial income from the sale of electricity, with well over $750,000 in retained surplus.[26].