Skip to Content


Nahant Marsh

A cache by Monjorgan Send Message to Owner Message this owner
Hidden : 8/4/2008
In Iowa, United States
1 out of 5
2 out of 5

Size: Size: not chosen (not chosen)

Join now to view geocache location details. It's free!


How Geocaching Works

Please note Use of services is subject to the terms and conditions in our disclaimer.

Geocache Description:

This Earthcache will bring you to the Nahant Marsh, one of the last remaining urban wetlands of its size on the Upper Mississippi River. The preserve proper, consisting of 513 acres, and surrounding lands is called Nahant Marsh Ecological Area.

From the 1960s to 1996, this land was used for skeet and trap shooting leaving Nahant Marsh contaminated with lead shot. In 1996, Nahant Marsh was listed as an Environmental Protection Agency Superfund site. In 1999, the EPA removed over 143 tons of lead-contaminated soil from 13 acres at a cost of $2 million. Following the clean-up, Nahant Marsh was designated as a nature preserve and educational/research center. The clean-up at Nahant Marsh is highlighted in the Advanced Technology Environmental and Energy Center’s (ATEEC) interactive CD-ROM “Brownfields in a Box.” Free downloads are available at (visit link)

In 2007, the Nahant Marsh Educational Center and River Action, Inc., partnered with Eastern Iowa Community College District (EICCD) and ATEEC to develop and oversee educational activities at Nahant. The Education Center offers hands-on activities to further the understanding of water quality, wetlands, and their importance to both wildlife and humans. Educational programming on wetland ecosystems, water quality, and biodiversity is offered at the Marsh.

Nahant Marsh was an oxbow of the Mississippi River that was cutoff resulting in the creation of an oxbow lake. Over time, the oxbow lake fills with sediment and, in the case of the Nahant Marsh area, a sedge meadow was created.
When the causeway to Credit Island was created, the river from the Marsh was blocked, causing severe sedimentation. In 1950, Nahant Marsh was predominantly a sedge meadow. The sedge meadow would have been dominated by sedges and grasses. Sedge meadows have long periods of saturated soils, with a tendency for the soils to dry out at the end of the growing season. Sedge meadows are dependent on winter or early spring inundation to provide soil saturation.

For an area to be considered a wetland it must be water-saturated for a minimum of 14 days during the growing season. Wetlands are generally comprised of Hydric soils (Soils with a thick layer of decomposing plant material at the surface and anaerobic conditions during the growing season), and water-loving plants and animals. Other names used to describe a wetland include: Swamp, Bog, Bottomland, Wet Meadow, Seep, or Marsh.

Wetlands are important for:

Flood water storage - wetlands store and slowly release waters during periods of high rainfall and snowmelt.

Flood Conveyance - these areas serve as floodway areas by conveying flood flows from upstream to downstream points.

Sediment Filtration - wetland vegetation binds soil particles and retards the movement of sediment in slowly flowing water.

Wave Barriers - Wetland vegetation binds and protects soil from being carried away during times of higher water flow (flooding).

Aquifer Recharge/Discharge - water from wetland recharges groundwater or groundwater may discharge into the wetland.

Pollution Control - wetlands act as settling ponds, removing excess nutrients. Other nutrients/pollutants may be removed by filtering and by biological and chemical processes. (Some wetlands have been engineered to treat wastewater!)

Fish and Wildlife Habitat - wetlands provide water, food, and nesting and resting areas.

Recreation – Wetlands provide fish, wildlife, and water for recreational purposes.

The I-280 Bridge bisects the marsh area. The plant communities vary on either side of I-280. East of I-280, the area is primarily marsh dominated by cattails. West of I-280, the area is predominantly open water with emergent vegetation and floodplain forest.

Plants that have been identified East of I-280 include: Cattails, River Bulrush and other bulrush species, Sedges, Rice Cut Grass

Plants that have been identified West of I-280 include: Silver Maple, Slippery Elm, Green Ash, Red-osier, Dogwood, White Mulberry, Bur Cucumber, Riverbank Grape, Smartweeds.

Estimates calculate around 130 species are believed to use Nahant area.

76 species potentially breed in Nahant. 32% have wetland dependent life cycles. Some bird species use Nahant as a resting or staging area during migration.

Start your self-guided walking tour: River way kiosk trail entrance. Walk to the trail through the access point in the fence. Turn left to the River bottom woods. To your right as you approach the woods is part of the prairie field that has been restored. Enter the lowland woods of the river bottom. Walk slowly and quietly to the stairs to the bird blind. Take a moment to watch for birds. As you walk over the boardwalk, stop at the overlook to view the vernal pond and wood duck houses. Exiting the boardwalk, turn left and follow the mown trail between the trees and mesic prairie. Bear left where the trees end, and check the vernal pond. In the spring, or with heavy rains, the basin fills and there will be frogs and ducks there. Continue along the mown trail to the Dock. This is a good spot to quietly observe waterfowl and aquatic plants and animals. Leaving the dock, continue east along the trail past the sedge meadow sign. At the fork, walk the trail through the hemi-marsh prairie meadow to the Education Center and visit the butterfly garden on the west and south side of the building. Or, continue east where the trail goes through a former farmland and is a mixed upland tree/shrub community. Notice the apple trees to your left. A sandy area further out on the left is a turtle nesting area, and the trails end offers benches to sit and watch birds. Be careful of Poison Ivy along the trail! Leaves of three . . . let it be!

I would like to thank everyone at the Advanced Technology Environmental and Energy Center (ATEEC) and Brian Ritter for providing me with information about this site and allowing me to place this Earthcache. Check them out at (visit link)

The terrain for the Nahant Marsh Earthcache is mostly flat with one gentle incline to negotiate. The trails are mowed and flat for a nice easy hike. Park at the coordinates listed above and follow the directions outlined in the “Trail Information for the Self Guided Walk”.

Please read these carefully:

To receive credit for this Earthcache, you must complete the following four requirements and e-mail me the answers. Do not post your answers in your log entry, pictures are encouraged.

(1) Identify the first tree on the right side of the path as you enter the river bottom woods. To help you with your task use the trail kiosk located at N 41° 29.280 W 90° 38.295

(2) Using the trail kiosk located at N 41° 29.387 W 90° 38.186 identify what 4 amphibians are found at the Nahant Marsh

(3) Identify the primary soil type located at following coordinate N 41° 29.531 W 90° 37.969

(4) Continue along the trail to N 41° 29.577 W 90° 37.939. What species of creature might benefit from this area and why?

Additional Hints (No hints available.)



102 Logged Visits

Found it 98     Write note 3     Publish Listing 1     

View Logbook | View the Image Gallery of 57 images

**Warning! Spoilers may be included in the descriptions or links.

Current Time:
Last Updated: on 10/8/2017 7:01:40 PM Pacific Daylight Time (2:01 AM GMT)
Rendered From:Unknown
Coordinates are in the WGS84 datum

Return to the Top of the Page