A Northwoods Almanac for 9/28 – 10/11/12 by John Bates
9/13: Rick and Pat Schwai visited Hawk Ridge and were treated to both a glorious day and the second largest count number so far (6600+) this month. Pat noted, “I didn't expect the hawks to be flying so high that they were invisible to the naked eye and still tiny with my 8x32 binoculars.”
9/16: Jim Ferguson went out on Lake Tomahawk for a last day of summer pontooning and was surprised to come across two red-necked grebes. He observed, “The two birds stayed close together all the time. We also counted 39 loons. All the birds were on the western end of Tomahawk Lake.”
9/17 Sharon Lintereur in Lake Tomahawk watched a barred owl hunting in her woods and was able to get some fine pictures (see photo).
9/19: Ellen and Kit Deubler had a rare visitor, a bull moose, at their home on Elsie Lake in the Township of Lac du Flambeau (see photo).
9/23: Mary, Callie, and I were very lucky to come across three migrating Lapland longspurs on one of the dikes in Powell Marsh.
Bumper Crop of Acorns
Our native red oaks have outdone themselves this fall in their production of acorns. There are so many underfoot in places it’s hard to walk! Productive red oak trees can produce over 1,000 acorns in a banner year – some white oaks are known produce over 10,000 acorns with yields reaching as high as 6,000 pounds per acre. However, white oaks are quite uncommon in the Northwoods, attaining their northern range boundary usually a few counties south of us.
I’m sure a host of wildlife species have also taken note of the acorn bounty. Among birds, ruffed grouse, wild turkey, red-headed woodpeckers, blue jays, crows, white-breasted nuthatches , brown thrashers, rufous-sided towhees, and common grackles are heavy consumers of acorns. And though red oak acorns are more bitter due to their high tannic acid content than white oak acorns, many mammals consume them, chief among them being rodents and squirrels, as well as black bears and white-tailed deer. For deer, acorns are preferred above all other food items whenever and wherever they are available.
But wildlife are not the only consumers of acorns; people have consumed acorns for thousands of years. In fact, acorns are still a commercial food crop in China and Korea, and are harvested to a lesser degree in Mexico and Japan. You can buy acorn flour online right now from www.acornflour.org. Acorns were particularly important to certain tribes in California, comprising half of their diet! There, oaks were planted, transplanted, and intensively managed in “orchard-like” settings.
But what about Native American use of acorns in northern Wisconsin? The Woodland tribes of the Upper Great Lakes Region relied on seasonally abundant plant and animal resources, chief among them in the autumn being fall-spawning fish and wild rice. But archaeological evidence indicates that acorn use was also widespread, though the sweeter acorns (white and bur oak) were preferred over red oaks. Red oak acorns require leaching of their tannic acid to be edible, but the practice was common, as described in the Menominees by Huron Smith in 1923: “The acorn was boiled till almost cooked. The water was then thrown away. Then to water, two cups of wood ash were added. The acorns were put into a net and were pulled out of the water after boiling in this. The third time, they were simmered to clear them of lye water.” Smith added, “Because the red oak was so abundant in Ojibwe territory, the acorns were one of their most important starchy foods.”
Environmental Analysis of the Rest Lake Dam
On 9/15, the WDNR released an Environmental Analysis (EA) related to the eventual new operating order it will issue on the Rest Lake Dam. The purpose of the EA is to provide a factual disclosure of the levels and flows of the river and how the large community of species are impacted, the management alternatives considered, and their anticipated environmental impacts. Here is a beginning attempt at summarizing this complex document:
Summary of the Issue
The Rest Lake Dam, located on the Manitowish River in Manitowish Waters and incorporated into the County ‘W’ bridge, creates an upstream reservoir that controls the water level on a chain of ten natural lakes and river channels known as the Manitowish Chain of Lakes. Elevations upstream of the dam are raised between 9.2 and 13.5 feet.
Downstream of the dam, the Manitowish River flows through three small lakes and then travels another 15 miles until the Manitowish and Bear Rivers combine to form the North Fork of the Flambeau River, eventually flowing into the Turtle-Flambeau Flowage.
The chain of lakes is drawn down about 3.5 feet every fall to protect piers and boat houses on the Chain. The drawdown results in significant autumn flooding downstream. The Chain is then refilled every spring after most of the ice is off Rest Lake, which unfortunately is after nearly all of the snowmelt has already gone downstream. Based on USGS estimates, to raise or lower the Chain 1 inch takes 14.8 million cubic feet of water. This amount of water translates to a daily flow of 171 cubic feet per second that is either taken from, or added to river flows downstream of the dam. The natural streamflow below the dam is thus profoundly altered in order to empty or fill the Chain – photographs throughout the EA dramatically illustrate this.
The current owner of the Rest Lake Dam is Xcel Energy. The hydropower generated downstream resulting from the fall drawdown of the Chain was evaluated by the Federal Energy Regulatory Commission, which in 2001 concluded that the management of water levels and flows was “neither used and useful nor necessary or appropriate to maintain or operate” hydropower generation.
Thus, given that the dam has no functional value to Xcel, its current operation is summarized by the EA as “focused primarily on upstream water interests including minimizing possible ice damage to piers and shoreline structures, as well as keeping water levels above the dam in a narrow operating range near the maximum water level from June through October.”
According to the EA, the problem with this management strategy is that at any time of year, the minimum river flow required at a dam stems from Chapter 31.34 Wisconsin Statutes, which states that a dam must, at the minimum, discharge at least 25% of the stream’s natural low flow. This is calculated by estimating the “Q7-10 flow” which is defined as the lowest average flow for a consecutive seven-day period with an average recurrence interval of ten years. The Q7-10 is mainly used for the permitting of wastewater discharges, and, importantly, these flows are not considered protective of aquatic life and habitat. The USGS has since estimated the Q7-10 for the Manitowish River to be 40 cubic feet per second (cfs).
The downstream flows of the Manitowish, however, have often been lower than 40 cfs, sometimes for months at a time, and thus of very significant ecological concern. So, the DNR began meetings in 2002 to re-evaluate the 1937 operating order that today still acts as the legal directive for the management of the dam.
The other statutory issue surrounding the management of the Rest Lake Dam stems from Wisconsin’s Public Trust Doctrine (Wisconsin Constitution: Article IX, Section 1), which establishes public water rights and the State’s obligation to protect those rights in navigable bodies of water. The Wisconsin Supreme Court has declared that the State holds navigable waters in trust for all citizens, and that public water rights such as water quality, quantity, scenic beauty, and recreational use need to be protected for the benefit of current and future generations.
In response to these statutory directives, intensive data-collecting studies were eventually undertaken by the DNR, and in November of 2009, the USGS placed gaging stations to record the river flow on the three largest inflows to the Chain (the Manitowish River, Rice Creek, and Trout River), the water level elevation at the dam, and the river flows downstream of the dam. This information, along with historical dam operating records and nearby long term gaging stations on the Bear and Trout Rivers were used by USGS to develop inflow models for the Manitowish River at the Rest Lake Dam.
Other information gathered in the EA addressed the major sources of water loss from the Chain and the rivers, which include water withdrawals for cranberry operations, private irrigation, evaporation, and plant transpiration. It also evaluated other issues such as water quality, aquatic habitat with discussion of the functions and values of wetlands, fisheries populations and habitats, wildlife populations including birds, mammals, amphibians and reptiles, and mussels, wild rice habitat, and cultural values such as local economics, land values, recreational uses, and shoreline structures.
Cranberry Growers Water Withdrawals
The entire EA is thorough, essential reading and quite revealing. For instance, the EA quantifies what the actual water withdrawals are from the three cranberry operations around the Manitowish and Trout Rivers.
Cranberry production uses water to irrigate cranberries during the growing season, to flood beds for harvest in August, to flood beds in winter to protect the vines from freezing/drying, and to either flood beds or irrigate to protect the plants from frost in the spring.
Approximately 960 acres of cranberry production is located downstream of Wild Rice Lake where pumps keep water levels high on Little Trout Lake, from which water is then pumped or flowed to individual cranberry beds. Water diverted to these cranberry beds is likely not returned to the Manitowish Chain because it is located in the Bear River sub-watershed.
The pumping station is only operated when water levels on Little Trout Lake are low during dry years. In 2007, a drought year, operating records indicate that pumping occurred 24 hours a day from June to October. Given the 10-14 cfs pumping rate from this operation, the USGS estimated the amount of water withdrawn from the Chain and diverted to Little Trout Lake ranged from 11 to 27% of the natural inflow of the river.
Another cranberry pumping station located upstream of Wild Rice Lake is used to keep water levels high on Great and Little Corn Lakes. Approximately 177 acres of cranberry production occurs in this location. This cranberry operation diverts from 2 to 100 percent of the flow of the Trout River when the pumps are turned on. For example, on December 11, 2009, USGS measured 2.41 cfs below the pumps and 25.0 cfs upstream (a diversion of 22 cfs). This means that under low flow conditions, the pumping rates can and were measured by the USGS gage to temporarily reverse the direction of flow on the Trout River.
The third cranberry pumping location has approximately 41 acres of cranberry beds and takes water out of Alder Lake, recycling it directly back to where it was withdrawn minus losses due to evaporation and evapotranspiration.
A fourth operation is currently under construction in the watershed that will have approximately 20 acres of cranberry beds, and which will divert water from Lower Gresham Lake. The outlet of this lake is Gresham Creek, which is a tributary to the Trout River upstream of Wild Rice Lake.
Operating Order Yet to Come
The draft EA is available for public review and can be downloaded at: http://dnr.wi.gov/water/basin/upwis/restlakedam.
Comments on the draft EA need to be received by the DNR by 10/31/12. An updated Rest Lake Dam operating order will be drafted after the certification of the EA.
I highly recommend reading the EA. It’s a lesson in the complexity of natural systems and our relationships to them. My hope is that objective and bighearted discussion will follow, the sustainable management of the rivers and the Chain will ensue, and people will come together to work with the DNR to optimize the health and integrity of the rivers and lakes throughout this watershed.
Please share your outdoor sightings and thoughts: call me at 715-476-2828, drop me an e-mail at firstname.lastname@example.org, or snail-mail me at 4245N Hwy. 47, Mercer, WI 54547.