Weeds

Weeds are plants out of place. In lakes, rooted plants may become weeds when they interfere with swimming, boating, fishing and other recreational activities. Native plants, those plants native to the lake, are for the most part beneficial. Native plants provide stability for the lake bottom, are habitat for various bugs and invertebrate animals, improve water quality and provide cover and habitat for fish. Prior to milfoil, an exotic plant, native plants sometimes posed a nuisance.

The nuisances posed by milfoil are greater than those posed by native plants simply because it grows earlier, faster, denser, higher, blah, blah, blah. In addition, milfoil also causes harm to the ecology of the lake because it harms native plants (the good ones). So the imperative for controlling milfoil is much greater.

I also hear that anglers like milfoil, so they argue it is also beneficial. It is true, in some areas game fish may congregate in milfoil and some anglers have learned to fish there. In this sense, milfoil is good for fishing. However, milfoil is not good for fish – for all the reasons I mentioned above – milfoil is not good for lake health. All that said, most anglers actually do not like milfoil. DNR’s regional fishery manager has told me he gets many complaints from anglers that milfoil interferes with fishing.

So in Lake Minnetonka we have two kinds of weeds – good weeds and bad weeds. The Lake Minnetonka Association believes that our attention and focus should be on milfoil (the bad weed). Indeed, since I have been in this position (about 10 years), milfoil complaints have been and remain the number one concern. This does not mean that native plant nuisances have disappeared, rather they have been shadowed by milfoil.

It gets even more interesting. There is some evidence that in some areas, milfoil or milfoil harvesting may have actually increased the overall abundance of plants! As milfoil beds become established, they tend to increase the accumulation of underwater soils, making that area more hospitable to any kind of rooted plant growth. Unfortunately this has also resulted in less diversity of plants, so many of the increased native plants tend to be those with “weedier” characteristics. In addition, research done on Lake Minnetonka and other lakes around the country demonstrates that milfoil grows back more quickly in harvested areas compared to un-harvested areas. Milfoil in Lake Minnetonka exploits both natural and artificial advantages making Lake Minnetonka weedier as a result.

Controlling milfoil to restore Lake Minnetonka to a condition of having to deal only with “normal” weeds is a huge challenge because milfoil is tough and Lake Minnetonka is large. Last month, I wrote about the Lake Minnetonka Association’s Milfoil-Free Minnetonka campaign to highlight our plan to rid the lake of milfoil. This plan will require broad support, but it is technically do-able.

So, let’s tackle the milfoil mess so we can get to a point where we only have to deal with native plant “weeds.”

Let us not forget there are other exotic plants nearing Lake Minnetonka. Hydrilla is more aggressive than milfoil, indeed it has been known to displace milfoil. Hydrilla is in Wisconsin. The Milfoil-Free Minnetonka campaign also has a strong prevention element because we do not want to add to the list lake problems.

Milfoil-Free Minnetonka

For the past several months, I have been articulating the Lake Minnetonka Association’s vision for Lake Minnetonka. Those columns have described the various elements of our vision and here I want to put them all together. I have made the case that 1) milfoil remains the number one problem in Lake Minnetonka, 2) there are new restorative technologies available for lake-wide milfoil control, 3) zebra mussels and several additional exotic plants, animals and viruses are nearing Lake Minnetonka, and 4) we lack a comprehensive protection plan.

Added to this list is the fact that our investment in protection and control for aquatic invasive species (AIS) is woefully insufficient.

The Lake Minnetonka Association’s “Milfoil-Free Minnetonka” campaign aims to provide a mechanism for protecting and managing Lake Minnetonka – arguably the most significant recreational lake in the state and certainly the economic engine for the communities surrounding the lake.

Milfoil-Free Minnetonka is about ridding Lake Minnetonka of milfoil and preventing new AIS from gaining a foothold in the lake. We now know we can accomplish the former, albeit at a cost, and we believe we can accomplish the latter, but only if we change the game.

There are two significant hurdles – funding and attitudes.

I have done an analysis of the funding needs for accomplishing our vision based on a program analysis and comparing to what other lakes spend for these activities. Simply, the funding needed to adequately protect and manage Lake Minnetonka for AIS concerns is about ten- to twenty-times what is now being spent. For example, Lake Manitou, Indiana, spends about $500,000 per year for their hydrilla control program. Lake Manitou is 700 acres, so by comparison this lake spends about 5-times more than Lake Minnetonka and is 20-times smaller.

This funding gap should not be a surprise as Lake Minnetonka is really of a size and complexity to be more like two dozen lakes. The LMCD has a statutory funding cap which means it cannot adequately address these needs. Also, other agencies, such as the Minnehaha Creek Watershed District and the MN DNR, defer much of the AIS program activities to the LMCD, so in effect the LMCD is left high and dry to manage these concerns without sufficient resources.

The Lake Minnetonka Association has recommended new ways of funding to address this shortfall. We have recommended fees for boats using Lake Minnetonka, but there may be other mechanisms as well. Mayor Chris Lizee of Shorewood has shown leadership in proposing to establish an environmental fund that would support these kinds of activities. This fund would be established by investing the proceeds from the sale of the City’s liquor stores. As well, Lake Minnetonka is a regional asset and therefore some kind of regional funding is also appropriate.

It is easy to be complacent in the face of the AIS challenge. As Pete Nelson, former Director of the LMCD said, “the only thing harder than zebra mussels to eradicate is the notion that their introduction is inevitable.” And, even if zebra mussels get into the lake, we must not let up because each new AIS diminishes the integrity of the lake ecosystem. As well, unlike milfoil, which can be controlled, most new AIS have no remedies – none!

So, if zebra mussels get in, they will change the way milfoil grows, most likely more aggressively. Then if rusty crayfish (or spiny waterflea or hydrilla or VHS or ???) get in they will arrive in a system that is already stressed and their impacts will become synergistic – and not in a good way.

Milfoil-Free Minnetonka is an aggressive and ambitious plan that includes six key elements:

1. Expand the milfoil treatments
2. Monitoring and surveillance
3. Prevention
4. Early detection and rapid response
5. Research
6. Education

Each of these action steps has a more detailed plan, some of which have already been described in previous columns.

Three and four decades ago, Lake Minnetonka was a pea soup of algae. The community took action and now Lake Minnetonka is markedly improved. In that case the pollution causing the stinky algae was diverted and the lake responded. I believe the impacts of AIS to Lake Minnetonka can be more severe than sewage pollution. Unfortunately, we cannot ‘turn off’ or divert AIS introductions. However, the model of community action and investment has succeeded in the past and will succeed again. Let’s make Lake Minnetonka milfoil-free.

Aquatic Invasive Species - What is the Risk?

Previously, I articulated the Lake Minnetonka Association’s position and vision on aquatic invasive species, or AIS, prevention programs. There I cited six specific elements of a protection plan and ended with a recommendation that the overall protection efforts should reduce the risk of AIS introductions by 90%.

Here, I will provide a rationale and objective basis for evaluating the risk as well as the reduction of risk that is needed. While some of this is technical, I can (hopefully) convey the message without it sounding like an insurance seminar.

AIS are introduced into lakes by contaminated boats and trailers. Therefore, sources of entry for boats and trailers are the obvious mode of introduction. I have prepared a detailed risk analysis that examines various sources of entry and weighs this against risk of carrying AIS. The detailed analysis document is available on our web site. Here, I will give the highlights and discuss Lake Minnetonka’s vulnerabilities.

Boats enter Lake Minnetonka from these categorical sources:

• Public Access – Boat ramps owned and operated by public agencies
• Commercial Access – Commercial facilities, such as marinas
• Municipal Docks – Municipal docking facilities
• Riparian (lakeshore) – Individual lakeshore owners
• Special Events – Events, such as fishing tournaments and sailing regatta that require permits
• Tributary Lakes – Lakes that flow into Lake Minnetonka

I have developed metrics that provide an indication of the risk of AIS introductions from each of these sources. The details of my analysis are contained in a technical document (available on our web site). The risks from each source are:

Public Access 84%

Commercial Access 3%

Municipal Docks (rented from cities) 0

Riparian 0

Special Events 3%

Tributary Lakes 9%

This clearly points to public accesses as the primary point of a prevention program; although the others should not be ignored. The zero risk from municipal and riparian docks are due to the fact that these boats do not leave the lake.

The good news is the protection programs now in place do indeed emphasize public accesses. The bad news is there is not enough coverage.

With the above-referenced risk analysis as a basis, it is possible to evaluate the degree of risk reduction now in place. For example, the LMCD’s program of inspectors and automatic video monitors covers four of the most heavily-used public accesses during the summer. Assuming these accesses traffic 50% of the boat use volume and that the period of inspections and monitoring covers two thirds of the boat use season, the overall risk reduction would be 28%, which is short of what we have recommended. Also note that this reduction assumes the inspections or monitoring are 100% effective at stopping AIS, which is probably unrealistic.

This makes the case for additional protection. This can happen by increasing the scope of current programs or restricting access points (but not access) to funnel more boats through protected accesses.

This risk analysis provides an objective framework to plan an effective AIS protection plan. Clearly, Lake Minnetonka is now highly exposed to an AIS introduction. While additional solutions will be challenging, we should approach the protection of our lake with open eyes to provide the greatest protection.

A Vision for Aquatic Invasive Species Protection

This is the second in a series of article articulating the Lake Minnetonka Association’s vision for Lake Minnetonka.

The Lake Minnetonka Association’s vision for better protection against aquatic invasive species, or AIS, is that aggressive and comprehensive protection is needed, some of these measures will require new thinking and we are now largely unprotected.

AIS not yet in Lake Minnetonka include zebra mussel, spiny waterflea, hydrilla and viral hemorrhagic septicemia – and there are many more as well. All of these invasive plants, animals and viruses are brought into lakes by boats and trailers, which makes the focus of prevention actions easy, at least in concept. The challenge will be to implement meaningful and effective protections while at the same time minimizing inconvenience and maintaining rights to use this public resource.

The Lake Minnetonka Association believes that a) the level of protection is not currently adequate and b) because for most of the new AIS there are no remedies, protection is the only practical strategy.

Our prevention plan includes six elements:

1. Comprehensive Physical Inspections using human or automated approaches are critical. Currently, human inspectors or automated devices cover about 1/3 of the total boat activity at public launches. Inspections should also require assurances that incoming boats and trailers are dry inside and out. The Lake Minnetonka Association recommends all public, private and municipal access have inspectors or automatic surveillance and current LMCD ordinances be enforced.

2. Closure of Some Accesses

Because there are many public and private accesses on Lake Minnetonka, the prospect of comprehensive coverage with inspectors is costly and inefficient. To better facilitate effective inspections, some access should be closed at some times. Because Lake Minnetonka is a public resource, assurances should be provided to permit access to the lake with a minimum disruption and inconvenience. The Lake Minnetonka Association recommends some accesses be closed at some times to facilitate the comprehensive inspections recommended above, but assurances should be provided to not restrict public access overall.

3. Fees

Because AIS are transported via boats and trailers, a fee based on boat/trailer usage is proportional to the risk of introducing AIS. There will be costs for implementing many of the protection elements in this plan, so assessing fees based on boat/trailer usage is reasonable. There are historical, cultural and policy hurdles to overcome for this proposal. The Lake Minnetonka Association recommends fees be assessed to boats and trailers using Lake Minnetonka to support AIS prevention programs.

4. Tributary Lakes

AIS introductions in lakes that are tributary to Lake Minnetonka will have a ready access to Lake Minnetonka via their surface water connections. Therefore the protection activities we propose should be applied to tributary lakes as well as to Lake Minnetonka. The Lake Minnetonka Association recommends prevention activities, such as inspections, restrictions and fees, should be implemented on lakes that are tributary to Lake Minnetonka.

5. Inspections at Special Events

The Lake Minnetonka Conservation District should enforce its AIS provisions for Special Event participants. To our knowledge, the inspections or washings as required in the ordinance are not occurring. The Lake Minnetonka Association recommends that inspections and/or washing of all watercraft participating in Special Events be required. Further, because participants in Special Events include out-of-state watercraft, we recommend all participating watercraft demonstrate they contain no water in their live wells or no live bait.

6. Enforcement

The Lake Minnetonka Conservation District should upgrade and enforce its prohibitions. The LMCD code prohibits any plant fragments on boats or trailers within boat launch areas. This has not been enforced. The LMCD ordinance does not specifically define or prohibit other AIS. The Lake Minnetonka Association recommends the LMCD’s ordinance should be amended to specifically include prohibited and regulated invasive species. The LMCD should better enforce the above-referenced sections of its ordinances.

Acceptable Risk

There is no practical way to reduce the risk of AIS introductions to zero. However, the Lake Minnetonka Association believes AIS prevention must substantially reduce the risk of AIS introductions. Furthermore, unless the risks are substantially reduced, half-measures are poor public investments. The Lake Minnetonka Association recommends the overall risk of AIS introductions be reduced by at least 90% compared to the present baseline.

The complete position statement (Prevention of Aquatic Invasive Species) can be found on our web site.

We believe the new thinking we present will help the overall efforts to better protect and manage Lake Minnetonka now and in the future.

A Vision for Better Environmental Protection of Lake Minnetonka

The Lake Minnetonka Association is dedicated to the sound environmental management and protection of Lake Minnetonka. As I outlined in last month’s column, there is a lack of a clear vision for protection and management of our lake. Here and in the next several columns, I want to articulate the Lake Minnetonka Association’s vision for Lake Minnetonka in several critical areas.

Future columns will address protection from zebra mussels and other new invasive plants, animals and viruses and a comprehensive approach for shoreland and nearshore protection and management. This column presents our vision for managing milfoil in Lake Minnetonka.

Our vision for milfoil management is to expand a long-term comprehensive restoration program throughout the lake.

Milfoil has been managed primarily through the harvesting program of the Lake Minnetonka Conservation District. This program, established in 1989, harvests (or cuts) and removes milfoil in targeted areas around the lake. While the program is managed and administered effectively; there are limitations to what harvesting can accomplish.

Stakeholders from three bays (Carmans, Grays and Phelps) had these views regarding the harvesting program: only 16% of respondents thought the harvesting program was effective and 76% thought it is short-term, small-scale or ineffective. In addition, the number of acres harvested has decreased by 100% since 1989. In 2007, only 323 acres were harvested.

New science is now available that offers advantages in the ability to actually restore native plants while controlling milfoil. The use of herbicides, as has been proposed for Carmans, Grays and Phelps Bays in 2008, is safe and restorative. The Lake Minnetonka Association believes the harvesting program should be phased out and replaced with a program that is restorative and will treat much larger areas of the lake.

Here is why we think this makes sense:

Herbicides are available that can selectively control milfoil and protect native plants. Compared to harvesting, selective herbicides have these advantages:

• Selective herbicides are safe and a restorative.
• Selective herbicides will actually control milfoil over large areas and for multiple seasons.
• Selective herbicides are applied early in the season and their use will diminish over time.
• There are no capital investments.
• Significant reductions in lakeshore cleanup are expected.

Another significant advantage is that larger areas of milfoil can be controlled within the same budget as is now available for the harvesting program. Our analysis indicates the number of acres of milfoil controlled could increase by five-fold within the same operating budget for the harvesting program. We propose involving lakeshore owners as private funding partners in this program, because they have demonstrated a willingness to help protect this public lake.

Our complete analysis can be found on our web site in a document titled, “LMA Position Statement on Milfoil Management.”

We believe the new thinking we present will help the overall efforts to better protect and manage Lake Minnetonka now and in the future.

A Vision for Lake Minnetonka

Lake Minnetonka is much cleaner today that it was 20, 30, even 50 years ago. The main reason is the diversion of six sewage treatment plants that discharged directly into the lake. Nutrients in the sewage discharge spawned incredible and legendary algae blooms. By taking away the sewage inputs, the lake got cleaner, and it appears we have finally reached a new condition. Of course there will always be problems with respect to nutrients, like phosphorus in runoff pollution, but for now the situation is under control and we can look forward to enjoying a cleaner lake, especially compared to the recent past.

Now there are other kinds of pollution and impacts that are cause for concern. As a community, we should be aware of and orient our programs toward these impacts, so we can keep Lake Minnetonka clean and healthy.

Unfortunately, there is no clear vision regarding prioritizing these threats or investments for preventing or minimizing these threats.

Lake Minnetonka faces serious threats in three areas – aquatic invasive species (AIS) prevention, aquatic invasive species control and nearshore impacts, in that order.

AIS prevention must be the top priority for Lake Minnetonka. The reason is simple: As additional AIS enter the lake, its quality and condition diminish irreparably and permanently. The Great Lakes have had a century of AIS introductions and ecologists refer to the Great Lakes ecosystem as a train wreck. Lake Minnetonka has been lucky, not having a new exotic species introduction for about 20 years. However, we are tempting fate and much more investment is needed to keep new AIS at bay. I don’t think anyone has the “train wreck” vision for Lake Minnetonka.

The Lake Minnetonka Association’s vision for Lake Minnetonka is to keep zebra mussel, viral hemorrhagic septicemia, spiny waterflea and a bout a dozen other harmful AIS at our doorstep out of the lake. We have developed a plan to accomplish this, but it has not received serious consideration. AIS prevention efforts to-date have occurred in the absence of a plan or a meaningful strategic context. We remain highly exposed and can do much better.

AIS control is our next priority. Eurasian watermilfoil and curlyleaf pondweed are now in Lake Minnetonka. We have developed and proposed scientifically valid treatments to control milfoil and curlyleaf pondweed in the three bay Lake Vegetation Management Plan in 2008. This program is a stepping stone to a larger, more comprehensive and ecologically valid solution to milfoil control.

The Lake Minnetonka Association’s vision for Lake Minnetonka is to provide lake-wide milfoil control making Lake Minnetonka healthier and more pleasant for boating, swimming and other recreation.

Our last priority is to assure the nearshore land and shallow water areas on Lake Minnetonka are well managed. Nearshore areas are important for fish and wildlife habitat and therefore impacts in these areas are a concern. There have been a number of proposals and initiatives recently that attempt to protect nearshore areas, but these proposed remedies have been piecemeal and poorly focused. The lakeshore on Lake Minnetonka is arguably the most urbanized and developed of any lake in Minnesota, yet our beautiful lake boasts a world-class bass fishery as well as a healthy fishery overall. There is clearly not an imminent threat.

Lacking any clear threat should not be justification for turning our backs on these concerns however. Rather, shoreland protection and management should rely on facts and good science. Good policy and regulations should be developed to discover whether or how:

· nearshore buffers are needed or best implemented

· docks and related boating activities affect fish and wildlife

· artificial shoreland structures add to or detract from fish, wildlife and environmental values

While much of the lakeshore has been developed, there remain nearshore wetlands and sensitive areas that ought to be protected. These areas should be identified and specifically protected.

The Lake Minnetonka Association’s vision for Lake Minnetonka is the lakeshore be fully used and enjoyed without harming the Lake Minnetonka’s environmental values. Lakeshore owners should have the right to use these areas reasonably and have the obligation to assure that their use does not harm the lake. Right now, there appears to be a good balance, as Lake Minnetonka’s overall nearshore health is good.

Of course the devil is always in the details. Unfortunately there is not an official comprehensive vision or plan in place to assure that investments toward accomplishing these visions will occur. The Lake Minnetonka Association believes it is time for the entire Lake Minnetonka community to become engaged in protecting this wonderful asset.

Who Chould Pay for Milfoil Control?

Milfoil is a big problem. That is why the Lake Minnetonka Association and the Lake Minnetonka Conservation District have been preparing a vegetation management plan for three of the worst milfoil bays on Lake Minnetonka (Carmen’s, Gray’s and Phelp’s). We now know two important things: 1) the proposed bay-wide herbicide treatments are expected to control milfoil and curlyleaf pondweed (another exotic plant) and 2) the costs for these treatments.

We have received strong support for the proposed treatments. However, the costs are significant and serious questions of who pays for these treatments have been raised.

Who should pay for these treatments – both in the short-term and in the long-term?

A proposed five-year treatment program is estimated to cost up to $190,000 (Carmen’s), $259,000 (Gray’s) and $247,000 (Phelp’s). We have a good feeling for the costs the first year, but subsequent years’ treatment costs depend on the results from the prior years, so our estimates are probably high for the five-year program. For this reason, our discussions have focused on the costs for the first year. In the long run, if this program is sustained, I expect the annual costs to be about one fifth of the first year costs to maintain essentially milfoil-free bays.

So, here I focus on the first year (2008) as that is the most significant hurdle to overcome.

The estimated costs for the proposed treatments in 2008 are: $53,000 (Carmen’s), $75,000 (Gray’s) and $71,000 (Phelp’s). The good news is we will apply for and hope to receive grants from the DNR that will reduce the local costs by $10,000 to $15,000 (depending on bay size). The LMCD has committed $5,000 per bay. So, the remaining costs will be: $33,000 (Carmen’s), $60,000 (Gray’s) and $51,000 (Phelp’s).

With the anticipated state (DNR) grants, plus the LMCD contribution, the lakeshore owners will be asked to contribute between 62 and 80% of the project costs for 2008 – these percentages would go up in future years if the DNR or LMCD funding are dropped. This is wrong.

The DNR funds come from a boat license surcharge for every boat in Minnesota. So these funds are to a degree tied to the movement of milfoil (by boats). The state then re-distributes this money through grants for milfoil treatments, such as are proposed here. However, there is no assurance Lake Minnetonka projects will receive these funds, as the grants are competitive.

At the local level, we have argued, as have many lakeshore owners in the three bays, that at a minimum the LMCD should contribute at least the amount of money that would be spent on harvesting because there will be not harvesting in these bays if the treatments occur. I have estimated this to be $31,000 based on the harvesting program’s record averaging 30% in the three bays and an annual budget of $105,000. Simply, it is wrong to ask the lakeshore owners in these bays to both pay a disproportionate share and continue paying for the harvesting (with public funds) which will now occur in other bays. In addition, the LMCD contribution comes from their Save-the-Lake Fund, a fund with a $265,000 balance that has been raised from private contributions and is not public money.

As a side note, it is also time to re-evaluate the harvesting program in light of more advanced milfoil controls, such as are being proposed. Indeed, only 16% of survey respondents in this program thought the harvesting program was effective and 76% thought it is short-term, small-scale or ineffective. Science has moved past harvesting as a more effective long-term remedy for milfoil and other invasive plants in Lake Minnetonka.

Lake Minnetonka is a public resource for all to use and enjoy. I believe the lakeshore owners have a responsibility to make investments in keeping it clean and healthy; but I also believe our public agencies also have that responsibility. As it stands, there is an imbalance.

The window of opportunity for implementing this milfoil control project in 2008 is small, as the treatments would have to occur by early-May. I will be asking the lakeshore owners to support this project with funding as noted above, but their support is entirely voluntary. Regardless of what they choose, this level of private support is neither appropriate nor sustainable in the long run. For the sake of keeping Lake Minnetonka clean and healthy, I think the local communities, through the cities and LMCD, must also step up.