Water Quality Monitoring of Province Lake in 2008 Presented to PLA on July 18, 2009

2008 was the eighteenth consecutive year of water quality monitoring conducted at Province Lake. We sampled four times last season. The test results for 2008 on water samples collected by Steve & Mary Craig were reviewed by the New Hampshire Department of Environmental Services (NHDES). State reports for a number of years are available by clicking this web site.

Many of the terms below include hyperlinks to interesting related web sites. By clicking on most of the underlined terms, you can access additional information. If the same word is hyperlinked more than once, the different occurrences lead to different web sites. The NHDES report on the quality of water in the lake for 2008 indicates the following:

1. The average amount of algae in the lake in 2008 was virtually identical to that measured in the previous year, which itself was the lowest seen since 1999, as indicated by the chlorophyll-a concentration. We have never returned to the high levels observed during the weed removal activities of 1996 and 1997, and their lingering effects in 1998. The amount of algae is only 77% of the average for New Hampshire lakes. This low level is good because dying algae forms the brown floating bottom masses that come to your shore when the wind blows hard in July and August. The algae masses settle loosely on the bottom when the lake is still and cloud the water when wind or boat wakes stir things up.

2. Water transparency (a measure of how deep you can see into the water) was an average of 2.5 meters (8.1 feet), about 8 inches less than the previous year, which had been a very good year for us. As always, this was less than the statewide median of 3.2 meters (10.5 feet), but is not unreasonable considering that we have a shallow lake, so sediments are easily stirred up. The shallowness means that it is important to educate lake users on the importance of operating jet skis and boats at slow speeds in shallow areas to minimize disturbance to sediments and vegetation. Churning up the bottom sediments releases phosphorus, which promotes algae growth, increases turbidity (scattering of light by suspended particles), and decreases clarity.

The deepest part of the lake is only 16—17 feet deep, as shown on the bathymetric chart.

3. Phosphorus is a nutrient required for plant and algae growth and is typically the nutrient whose availability most limits plant and algae growth in NH lakes. The average phosphorus levels in the upper water layer in 2008 were also virtually identical to those measured in the previous year and were only slightly higher than in 50% of the lakes in NH (the median). In the lower water layer, the phosphorus levels were less than in the previous 3 years and were approximately equal to the NH median, but significantly below the median for lakes in NH that are similar to Province Lake. This is a good thing. Again, powered watercraft disturbance of bottom sediments is probably an important source of phosphorus for our lake. Too much phosphorus may increase the growth of plants and algae in the lake.

The phosphorus concentrations at the Rt. 153 Inlet and the Island Inlet on Bonnyman Road continue to be elevated. These locations have a history of elevated and fluctuating total phosphorus concentration.

4. We have never sampled Province Lake for nitrogen as part of the monitoring program. However, a 1987 DES Lake Assessment Program survey determined that plant and algae growth in Province Lake is actually limited by the amount of nitrogen, rather than by phosphorus. Therefore, it is important to be sure nitrogen-containing fertilizers are not used near the shoreline, or streams or ditches feeding the lake, and to be sure septic systems are operating properly.

5. Cyanobacteria (also known as blue-green algae) have occasionally been detected among plankton samples in Province Lake in the past. If present in large amounts, cyanobacteria can be toxic to animals and humans. Large concentrations would be caused by a bloom, which would be seen as the formation of a green, blue, or pink surface scum in a section of the lake. Bear in mind that this is different from the tan or yellowish foam seen sometimes after strong winds. It will likely look different than what you have seen before. While the current report does not mention cyanobacteria in our lake, please be aware that these bacteria are always here. Eleven other lakes in the VLAP program had cyanobacteria bloom conditions in 2008 that resulted in public health warnings to lake residents, two lakes for several months. While recreational exposure to cyanobacteria toxins is a major concern of NHDES, there have been no documented cases of cyanotoxin-related illnesses in New Hampshire.

If you think you are seeing a bloom, stay out of the water and call the NHDES Cyanobacteria Hotline at (603) 419-9229 to describe what you see. If suspicious, NHDES will sample and analyze the suspected bloom, then post a No Swimming advisory if there is any danger. They will monitor the situation and remove the postings when all is clear.

The best ways to avoid having cyanobacteria blooms are by eliminating fertilizer use on lawns, keeping the lake shore natural, protecting against shoreline erosion, and properly maintaining septic systems.

6. A pH between 6.0 to 7.0 is ideal for fish. Ours in 2008 was an average of 6.5, almost the same as the 6.6 average for the state. The pH at the Rt. 153 inlet was 5.7, more acidic than its long-term average of 6.0. Since it drains a large wetland, it has a high concentration of tannic, humic, and fulvic acids, which give it the color of tea and reduce its pH. No problem is indicated.

7. The dissolved oxygen concentration measured in June 2008 showed 95 to 100% saturation at all depths sampled in the deep part of the lake. A high oxygen level is a sign of the lake’s overall good health. I encourage powered watercraft to operate far from the shore to mix the deep waters and boost the oxygen concentration, while minimizing their operation in the shallows.

Loons and Lead: A recently released study[i] (in Northeastern Naturalist, June 2009) addressed the ingestion of lead objects by loons in the six New England states. Most birds swallow small stones to help them digest food. Many fishing sinkers fall into the size range that loons prefer. Loons can also eat fish that have fishing gear attached. Of 522 loon carcasses examined in the study, 118 had ingested one or more lead objects, 87% of which were fishing weights and 11% of which were firearms ammunition. Being fish-eaters, loons have a lower stomach pH than waterfowl that eat vegetation, such as geese and most ducks. The lower pH more effectively dissolves the lead, which then kills the bird. Poisoning from ingestion of lead objects is the № 1 cause of loon deaths in fresh water. Therefore, if you still own any lead fishing gear, please stop using it immediately. This web site, recommended in the study report, includes far more on the subject, including information about bans on the sale and/or use of lead sinkers in New Hampshire and Maine, and a list of manufacturers who sell lead-free alternative fishing gear. The Loon Preservation Committee visitor center is one of the many locations where old lead gear can be disposed of safely.

Asian Longhorned Beetle: The Asian Longhorned Beetle (ALB) is a tree-killing beetle 0.75 - 1.25 inches long, with long antennae and a black body covered with white spots. It is an invasive beetle that was first detected in New England in August 2008 in Worcester, Massachusetts. Since then, >$40 million have been spent removing and destroying about 24,000 trees so far in a quarantine area of >63 square miles. There is a fulltime staff of 40 working on this problem, operating out of a National Guard armory, with 30 more staff planned in the next 2 months. I present these statistics only to convey the seriousness of the infestation. This beetle attacks all hardwood trees except oak. It does not attack conifers. The major effort in Worcester has been taken to keep this beetle out of the New England forests, where an estimated $600 billion in damage would be possible. The Asian Longhorned Beetle affects you in two ways:

1. Please always use local firewood, to keep from spreading this beetle and other wood pests around. There is a up to a $25,000 fine for businesses knowingly removing wood from the Worcester quarantine area, with smaller fines for individuals moving wood for their personal use.

2. Watch for the beetle (July – October, most active in August), and more importantly, for signs of it.

· 3/8 to 1/2 inch diameter round exit holes, which may ooze sap

· Sawdust in tree crotches

· Tree leaves with only the midribs eaten out

· Trees dying from the top down (since the beetles and their larvae start eating at the top)

· Firewood with 3/8 to 1/2 inch diameter round tunnels through it, eaten out by the larvae

What To Do:

· If you suspect you see an Asian Longhorned Beetle, try to capture it. Place it in a jar and freeze it to kill it. It cannot bite you.

· Write down the exact location where you found it, and at what date and time.

· If you suspect you see tree damage from this beetle (but no beetle), write down the location of the tree and the nature of the damage. Tie survey tape or string on the tree, if you can.

· Call 866-702-9938 from anywhere in the northeast US to report your possible discovery. Your call will be relayed to the appropriate agency, based on the area code you call from.

· NOTE that all Asian Longhorned Beetle infestations in the US so far have first been discovered by individuals with no professional training. If you think you may have found something, don’t be shy. Tell the professionals and let them check it out. This beetle can appear anywhere infested wood may have been moved to, which makes areas in and around campgrounds especially vulnerable.

· You can learn much more at the following web sites: http://www.massnrc.org/pests/alb/
http://www.uvm.edu/albeetle/
http://www.dontmovefirewood.org/

THANK YOU NOTE: I want to thank Steve Craig for taking the lead on the sampling activity since 2004. Each year the State report grades each sampling program and each year Province Lake receives Excellent ratings for sample collection and submittal. Thank you to Steve, and others who have helped out from time to time! We can always use more volunteers to help Steve with sampling, deliveries, or both, so please contact Steve or me, or any member of the PLA board if you are interested in helping out. You may also use the general PLA e-mail address, info@ProvinceLake.org.

Respectfully submitted,

Norm Dudziak, P.E., I.M.

Independent subconsultant to full-service environmental consulting and engineering firm ESS Group, Inc.

The views contained in this report are my personal views and do not represent the views of ESS Group, Inc.

Province Lake Statistics from Appendix F of the State Report,
Which has Statistics for All VLAP Lakes

Maximum depth	4.9 meters	16.1 feet
Average depth	2.8 meters	9.2 feet
Volume	11,268,500 cubic meters	2.98 billion gallons
Lake area	410.37 hectares	1,014 acres	1.58 square miles
Watershed area[ii]	1,890.7 hectares	4,672 acres	7.30 square miles
Flush rate	1.0 time per year (annual outflow = lake volume)

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[i] Pokras, Mark; Kneeland, Michelle; Ludi, Anna; Golden, Ethan; Major, Andrew; Miconi, Rose; and Poppenga, Robert H. “Lead Objects Ingested by Common Loons in New England.” Northeastern Naturalist 16(2):177-182, Humboldt Field Research Institute, Steuben, Maine, June 30, 2009.

[ii] Watershed area includes the lake surface area.