Water Quality

In early 2017 Wenck Associates, Inc. staff met with Pine County Planning and Zoning staff, representatives from the Pokegama, Cross, and Windemere Lake Associations and the Minnesota Department of Natural Resources (MnDNR). The purpose of the meeting was to discuss management strategies to address concerns of AIS and promote growth of healthy submerged aquatic vegetation (SAV) communities within county lakes. The hyperlinks below give all the details of the work-to-date.

Aquatic Vegetation Management Plan

AVMP Plan with comments




The Lake Management Plan of the Cross Lake Association lists its commitment to assist in the completion of two demonstration shoreland restoration projects and then use these projects to educate other members.

In order to prepare for these projects, five board members along with a number of other CLA members, participated in the 2008 Summer Pine City Neighborhood Rain Garden Planting Project at Woodpecker Ridge.  Five thousand plants were planted in specially-constructed rain gardens designed to reduce run off of storm water to the Snake River and Cross Lake.  Good Job Pine City !


Analysis of two samples of water taken from a very high volume runoff into Cross Lake coming from fields and gullies east of Pine County 9 indicated a high bacteria count. It could not be determined at this time which specific varieties were involved, although it is believed that they were fecal coliform (Trent). Further investigation is necessary to determine the sources) of the bacteria. It will be especially important to determine if the source is the dumping of human waste from septic systems onto land that may drain to the lake.

Preliminary exploration of the extent of one of the gullies and surrounding alfalfa field already has been done by SWCD and CLA. Samples of the rusty-colored water were sent to ERA lab in Duluth to determine the phosphorous and nitrate concentrations (Yorston).  Even with low concentrations, the total load might be fairly high. Results are not available at this time.  The furthest eastward side of the bays north and south of Norway Point also were packed with a great deal of blue-green algae.  Other parts of the lake experience the same algae masses along the windward shore.  DNR Fisheries indicated that most of the mass accumulation would be due to the predominant wind from the south (a longstanding problem).  The very warm weather previous to the cold rainy spell was ideal on Cross Lake, and in many other parts of the state, to produce a fall blue algae bloom. An MPCA research scientist thinks that our bloom was likely Microcystis, one of three hazardous species common in eutrophic (high nutrient) lakes. Under certain conditions these species can be toxic if ingested or taken into the nose. Obviously, keep people and dogs out of anything resembling pea soup. The recent rapid run-off of nutrients may contributed to the heavy infestation.

Discussions are being held with the appropriate agencies regarding the cause of these problems. We will be looking for possible solutions, especially regarding heavy runoff in gullies.

By:  Jerry Trent  – Dean Yorston  – Judy Yorston , CLA Water Quality Team


Commonly called blue-green algae, they are a diverse group of primitive bacteria (cyanobacteria) capable of making their own food from carbon dioxide and water in the presence of the blue-green pigment plus sunlight. They need other nutrients including phosphorous and nitrogen dissolved in the lake or river. Nitrogen is usually not a limiting factor for their growth because they are able to convert nitrogen gas directly without it being converted to forms that most plants require. Blue-green algae also can move up and down in the water column to take advantage of sunlight. They may shade out desirable native plants during an algae “bloom”.

A variety of both green and blue-green algae are present in virtually all waters in Minnesota. During our monitoring of Cross Lake, Pokegama Lake, and the Snake River from May-September, we saw increasing amounts of them as the water warmed. A heavy “bloom” was everywhere, although there was somewhat less in the river as the summer drought continued.

Some varieties of blue-green algae produce toxins that affect humans and animals. Swimmers are more vulnerable if they get infested lake water into their noses. Wearing noseplugs would be helpful, but if the water is green, especially if it resembles pea soup and smells stay out of the water. Dogs should be kept out of infested waters since they may drink the water or lick themselves clean.

Both green and blue-green algae thrive in warm, shallow, nutrient rich lakes. The drought and high temperatures, along with lots of nutrients in the water, were ideal for a “bloom” this summer. The bloom has lasted longer this year, but of course it will die back before the lake freezes over. Unfortunately, the cycle repeats itself every year. We can hope for more rain in the year ahead to help “flush” out the excess nutrients, but we need a lot of cooperative effort on our part to have a reduction of phosphorous in the water. This nutrient has two general sources (1) the lake sediment that continues to form, and (2) the water that enters the lake/river continually in the form of runoff.

Reducing runoff is so important that the CLA plans to heavily promote methods for you to help in the important goal of cutting the amount of nutrient rich runoff from your shoreland, for example by using rain gardens and buffer strips. I know we have been singing this song for a while, but we need to look at this seriously. If you want to participate, the Pine County Soil and Water Conservation office in Hinckley has been very cooperative in helping our members. Would you like to participate in a planting demonstration site? Let us know.

By Jerry Trent, Water Quality Committee Chairperson

The Healthy Lakes and Rivers Partnership Program

After a preliminary meeting last spring, the Cross Lake Association was invited to participate in the Initiative Foundation’s Healthy Lakes and River Partnership Program along with six other associations in Pine and Chisago counties. Representatives from each association attended two five-hour training sessions on strategic planning, communication, and non-profit group leadership.

Representatives of many state and local agencies and non-profit organizations also attended the training sessions as resources. The Cross Lake Association was represented by Judy and Dean Yorston, Jerry and Dede DuBois and Jerry Trent.

We had a lot of opportunity to learn from other associations in this coalition about the nature of their lakes, as well as their issues and problems. The group decided to meet regularly in the future to track the problems, projects, and sources of funding, successes and failures.

After the first training session, the CLA team met for several hours to plan a presentation to the other lake associations at our second training session.

The next step was the preparation of a Visioning/Planning Session to which the public and various local government representatives would be invited. It was decided by the two teams that Pokegama and Cross Lake Associations would hold a joint meeting and representatives would make written, oral and visual presentations.

On September 28th, Don Hickman and his associate led the 110 people who attended through a series of steps leading to focusing on three significant lake/river management issues:

1.   Invasive Exotic plants and animals. This includes: Identification,
impact, and control of Curleyleaf Pondweed,

Eurasian Milfoil, carp, etc. Replacement with useful native plants.
Methods and monitoring.

2.   Shoreland Management/lakescaping. Control of chemicals and nutrient
rich runoff. Water diversion, rain gardens, buffer strips. Control of
shoreline erosion.

3.   Water Quality. Emerging technology. Most people focus on algae
bloom, but the underlying cause-excess  nutrients dissolved in the
water-is more important and is very related to the success of number
2, as well as methods to reduce the amount of nutrients released from
the lake bottom sediment.

Many people volunteered to participate in committees dealing with these focus issues and will be meeting.

The major goal of the CLA team will be to develop a well thought out Lake Management Plan, and then select useful and approved projects, which are practical, sound, and can be funded. Results must be measurable in order to obtain outside funding.

The large amount of water quality data that we have been collecting will serve as a very useful base for determining progress and monitoring will need to continue.

By Jerry Trent, Water Quality Committee Chairperson

See the following web link for information on toxic algae:

Did You Know…?
The 100 mile-long Snake River drains parts of six counties and collects water from approximately 900 square miles comprised of 60% forest, 20% agricultural land, 10% wetland, and 10% wooded lots and residential.  This watershed is part of the St. Croix River Basin, a federally protected watershed, and in turn is part of the huge Mississippi River watershed running through the central UnitedStates to the Gulf of Mexico.

Water quality issues in the 1990s caused the Pokegama Lake and Cross Lake Associations to attempt to create a watershed improvement district with tax authority to address problems.  Instead of a new tax authority, the result was a court-ordered Snake River Watershed Management Board, with county commissioners representing four of the most affected counties, along with Soil and Water Conservation technicians and a Citizen’s Advisory Committee.  Director Dean Yorston represents Cross Lake Association.  Hundreds of thousands of dollars have been spent on numerous small projects, such as feedlot modifications and controlling serious erosion of shorelines on lakes and rivers of the watershed.  Property owners have paid 25% or more of the cost of the projects on their property.

Cross Lake is a little less than 1,000 acres, with over 12 miles of shoreline, an average depth of 15 feet, with bays on the north and south end typically less than 15 feet, and middle areas that are about 20-22 feet.  The area west of sunken island approaches 28 feet, and the small area of the lake where the Snake River enters the lake is the deepest spot at approximately 30 feet.   These depths vary, of course, with the general level of the lake season to season.  Lake level has varied from 931 feet above sea level in 1952 to 939 feet in 1965 – it is typically about 934 feet.  Note that in 2006, a summer drought year, the river continued a slow flow from relatively high water quality springs and wetlands and continued to spill over the Cross Lake dam.

During the late summer the water quality of the river as measured at the Pine City bridge was better than Cross Lake in terms of Secchi disk readings and amount of Chlorophyll a as seen as visible blue and green algae.

The littoral zone (approximately 2x the Secchi disk reading) of the lake is the area that is shallow enough to support rooted aquatic plants such as desirable native types – lily pads, wild celery, and coontail.  Unfortunately, undesirable Curleyleaf Pondweed is a significantly dominating weed in areas where it is not controlled by cutting and removal.  Native plants do develop each season in areas that have had Curleyleaf harvested from mid-May until about the first of June.  Native plants contribute to water quality.  The Association has sold many aquatic weed rakes and also loans 10 larger towable weed cutters to members.  (This is somewhat comparable to the battle in your yard to control dandelions, thistle, and Creeping Charlie!)

The Snake River watershed lies in what is considered the North Central Hardwood Forest ecoregion of Minnesota.  Typically, average summer water quality of Cross Lake as measured by amounts of Total Phosphate, and Chlorophyll a have exceeded the average for this ecoregion.  Secchi disk readings and monthly samples for phosphate and Chlorophyll are collected by the water quality team and analyzed by a lab.  Other lakes in the watershed have these factors tested also.   Data is sent to the Snake River Watershed to be compared to other information that is being collected over a 10-year period.

Cross Creek drains about 2,000 acres of mostly wetland on the north end of Cross Lake.  Two years of laboaratory analysis of chemical, physcal and bacteria samples indicated there were problems with water quality.  For the last two years several locations have been tested with two new methods of monitoring E. coli bacteria specifically and have shown occasional very high numbers after significant rainfall events.  In general, it appears that a major feedlot improvement project has benefitted at least a portion of this watershed.  Testing will continue next year.

Cross Lake stratifies during the summer – many lakes do this naturally.  This means that warmer, less dense water sits on top of cooler, more dense water and the top layer does not mix with the bottom layer (except to a small degree by the propeller thrust of powerful outboard motors – perhaps to a depth of 18 feet).  The denser bottom layer in the summer not only is not gaining oxygen from the surface layer by diffusion, wave action and photosynthesis, but also is losing oxygen due to decay of organic sediment.  Unfortunately, this condition allows for the chemical release of phosphate into the water column where it can become available later for algae production.

Serious oxygen reduction or depletion at depth restricts the zone that game fish will regularly inhabit.  This is compounded by the fact that they will likely tend to avoid the too warm, but oxygen-rich upper layer.  We are told that global warming will worsen this situation!

Why is the lake green?  Every property owner can reduce the movement of phosphate from the land to the lake and river.  Stop the use of fertilizer on shorelands, and discontinue applying any fertilizer on your property that contains phosphate.  One authority says that one handful of fertilizer with phosphate in it will cause an algae bloom one foot deep on one acre of lake surface!

It is also now clear that shoreland practices must be used to keep the soil and organic matter from entering the water.  You can slow the flow of stormwater runoff by planting native plants, shrubs and trees (their roots are far deeper than lawn grass and hold the soil better).  On the shoreland area, mow the grass less and as tall as possible or let it grow most of the season.  Rain gardens can be a shallow dip at the bottom of a slope that holds some stormwater, especially if the garden contains deep-rooted plants.  Pine County SWCD can provide you with assistance if you call them (320-384-7431).  Or E-mail:  marykay.anderson@mn.nacdnet.net.


Clean Water Tips For Cabin Owners

With many Minnesotans now performing the time-honored ritual of opening the lake cabin for the summer, there are several things they can keep in mind to protect lakes and streams from pollution:

o    Do you keep your shoreline in natural condition? If not, maybe this is the year to make the switch. Simply leaving an unmowed buffer at the shoreline can be a big help to water quality. Also, leaving “emergent” aquatic vegetation (shallow-water plants) in place provides great habitat for fish.

o    Avoid fertilizing the lawn. Nutrient runoff is a primary source of water pollution.

   Protect waterfowl by exchanging lead-containing fishing tackle for new, lead-free gear.

o    When cleaning up outside, remember that backyard garbage burning is illegal statewide, even for cabins. There are some exceptions to the law, but they’re for farmers only. For more information on backyard garbage burning go to www.pca.state.mn.us/oea/reduce/burnbarrel.cfm. For more information on obtaining the appropriate permit for burning approved vegetation, contact your local fire marshal or Department of Natural Resources office.

  Don’t drain last year’s gas from the mower or outboard onto the ground; use it up by mixing with fresh fuel.

o   Consider joining your local lake association. Water quality is one of the primary concerns for such groups.

  Become a volunteer water monitor.  The MPCA has volunteer monitoring programs.

Adapted from a May 24 MPCA Press Release.



Protect Your Lake by  ‘Lakescaping’
Lakescaping programs are helping to alter the definition of what the ideal lakeshore property should look like.  The ideal of suburban manicured lawns up to the water’s edge is being replaced by the practice of leaving a naturalized buffer stip between the lawn and the lake.

Lakescaping involves making decisions that protect water quality and the ecology of the lake and stream.  “It is evolving among lakeshore owners as a strategy to sustain natural beauty, while still enjoying the lakes’ recreational activities,” said Jenny Winkelman, DNR Aquatic Plant Restoration specialist.

Native plants that grow along the shoreline filter nutrients and pollutants before they enter the lake.  Their long root systems, often over five feet long, hold the soils in place and prevent erosion.  Avove ground, the stems and leaves of the native plants provide beauty and habitat for wildlife and butterflies.  Since native plants are adapted to local growing conditions, they don’t require chemicals to make them grow.

Lakeshore owners often are concerned whether they can still use their shoreline for swimming and other recreational activities.  A lakescaping plan is designed around the owners’ recreational needs.  Beaches, docks and nature pathways can be included in the natural buffer strip between the lake and the lawn.

More advanced techniques include introducing plants or seeds purchased at local, native plant nurseries.  This allows the homeowner to design a shoreline blooming with bountiful floral colors all summer without contributing to algae blooms in the lake.

Tips for creating a buffer zone:
1. Plant native trees, shrubs and pernennials between the lake home and the water’s edge to filter runoff, stabilize the shoreline, deter Canada geese, increase beauty and privacy, and reduce time spent on maintenance.

2. Look at nearby natural areas to see which plants will grow and to understand the potential of the lake.

3. Look carefully at the shoreline and protect the good plants that are trying to grow (they are right for that location and free).  Stop mowing and see what comes back on its own.

4. Naturalize a strip that is least 25 feet deep and includes as much of the frontage as possible.

5. Use only native plants.  They have long root systems that hold soils in place, aerate compacted soils, and help water filter into the soils instead of running off into the lake.

6. Avoid planting exotic plants and/or cultivars near the water’s edge.  They may escape and cause ecological problems.

7. Control weeds.

8. Reduce or stop fertilizing.  Use only phosphorous-free fertilizer on shorelines (the middle number on the bag should be “0”.  One pound of phosphorus can produce up to 500 pounds of aquatic plant or algae growth once it washes into the lake.

9. Get permits before planting or collecting plants from below the ordinary high water line.

Reprinted from the Pine City Pioneer.