News

Invasive Species Presentaton To PLIA Board

Amy Smagula, limnologist and Exotic Species Program Coordinator at the NH Department of Environmental Services (NHDES), addressed the PLIA Board of Directors at its November 15, 2016 meeting.  She spoke about Pawtuckaway Lake’s variable milfoil infestation, offering information and outlining recommendations for its management in the near future.

amy-smagula-addresses-boardHer plan of action included prevention, early detection, rapid response, and control efforts.  Amy spoke encouragingly about the fact that the infestation in Pawtuckaway Lake has been neither dense nor widespread so far, and advised the PLIA that its current campaign of containment and removal is a winning strategy that should be continued.

Amy cautioned, however, that variable milfoil is a formidable pest.  Even though no growth was apparent upon recent inspection of the lake by our Weed Watchers and NHDES biologists, it can lurk undetected to re-emerge in the early spring.  Milfoil can grow an inch a day in optimal conditions.  Further, it is capable of growing under the ice and is undisturbed by exposure to freezing temperatures and snow or frost.

Herbicide treatment is not recommended, as it must bond to actively growing plants to work and is only effective for about a 48 hour period.  For that reason, it is not a plan for prevention.  Due to the nature, location, and size of our infestation, Amy specifically said that herbicide treatment is definitely off the table.

Biweekly surveying of the lake by our Weed Watchers is recommended. Amy affirmed that the team who regularly patrolled the South Channel locating and marking milfoil growths this past season is crucial to the rapid response that NHDES certified divers have been able to provide.  The coordination of these efforts has thus far made it possible to eliminate new growths not long after they have been detected.

Curtailing boat and fishing traffic through the sensitive area of milfoil infestations near the State Park boat launch will remain a challenge, she acknowledged.  The real concern is that fragments broken off in the channel will be transported unknowingly to other parts of the lake where the weed may be harder to spot and will consequently spread.  In addition, engaging State Park personnel in education and awareness efforts will be a key component to our management plan.  She emphasized that our Lake Host Program must remain vigorous.

The Board expressed its appreciation to Amy for sharing her expertise and helping the PLIA address this situation in the most comprehensive and effective manner.  NHDES has been and continues to be our strongest ally in our fight to eliminate variable milfoil, offering its resources and assistance on a continuous basis.

In the coming 2017 season, the PLIA will be calling for assistance from its membership to join these efforts.  Please consider becoming a member, renewing a membership, or offering your time as a volunteer.  Further, we are looking for folks with PADI SCUBA diving credentials who are willing to take the State weed-control-diver-program training to help us with future eradication efforts.  For information, please contact PLIA Vice-President Tom Duffy at 603 303-3039, tom.duffy@verani.com .  Together we can win this battle!

 

PLIA Volunteers Pick Up Trash on Route 156

road-cleanup-fall-2016road-cleanup-fall-2016-2On the crisp, Saturday fall morning of November 5, 2016, members of the PLIA assembled at the telephone substation near Seaman’s Point Road to pick up litter on the highway.  They have adopted and are responsible for cleaning up a stretch of roadway along Route 156, which they do twice a year.  PLIA Board member John Morin organized the team and PLIA member Steve White coordinated with the State to support the activity. The White family has its own stretch of Route 156 which it also patrols for cleanup.  Although the temperatures were frosty, spirits were high as friends and neighbors shared stories of summer adventures as well as plans for the coming winter, all while bagging cans, bottles, and other debris strewn along the road.  Community service can be fun!road-cleanup-fall-2016-3

End of Season Milfoil Report

Those who have been following reports from the PLIA are aware that invasive Variable Milfoil has been in the South Channel for the past two summers. Throughout this time, PLIA volunteers have been snorkeling the area to discover new growths, which they have marked so that DES divers can remove them. milfoil-perimeter-for-web-pageAt one point, a local volunteer certified diver even donated his time to pull a lot of growth in early July.

milfoil-warning-signs-3As a result of the infestation, we have sent out notices and placed signs in the South Channel advising boaters to avoid the channel in order to minimize the possibility of fragmenting and spreading the milfoil. Currently, all known Variable Milfoil has been removed from the channel.

While it is very likely that the invasive milfoil has not been eradicated completely, the South Channel appears to be clear enough that boating can resume in the South Channel.

Consequently, the signs in the South Channel are being removed. In the spring we will resume searching the South Channel area for new infestations of milfoil and will send out notices and place the signs back in the channel if any new milfoil is found.

The PLIA would like to thank the people who went out of their way to avoid this area and recognize that their sacrifices and inconveniences played an important role in this effort.  As we know, it is impossible to stop all traffic through the South Channel, but we appreciate the efforts made by many boaters to avoid using it. We also appreciate all those who answered our call to spread the word, not the milfoil!

 

 

Pawtuckaway Lake Evaluation – Spring 2016 Update

Prepared by the NH Department of Environmental Services (NHDES)

Over the last year, NHDES continued its evaluation of Pawtuckaway Lake’s phosphorus, aquatic plant surveys and lake outflow volumes and phosphorus concentrations. Semi-annual meetings were held in spring and fall. A meeting was held September 17, 2015 in Nottingham where the summer relief pulses and the public hearings about the draft 2015 Report of the Instream Flow Pilot Program were discussed.

Lake Drawdown – On October 13, 2015 the NHDES Dam Bureau started the fall drawdown by opening the Drowns gate and removing a stoplog from Dolloff dam, which was subsequently replaced. Most of the flow from Pawtuckaway during the last two years’ drawdown had gone through Drowns. Initially, the target release ratio was 70:30 (Drowns: Dolloff), but later the ratio drifted to a 90:10 split in trying to maximize phosphorus export. However, this has resulted in long periods when the Pawtuckaway River received no flow other than leakage. This is much less than is needed to support that river’s ecosystem.  A more balanced release will occur next time while still preferentially releasing higher phosphorus concentrations at Drowns. From October 30 to November 1, NHDES rerouted all outflow through Dolloff Dam when Fish & Game Department requested that alewives needed egress from the lake over Dolloff Dam. NHDES and NH Fish & Game are conferring on how to operate the drawdown to support the alewives’ migration out of the lake.

2015 Phosphorus values – Phosphorus export during the fall of 2015 was significantly less than in 2014. From October 10 to December 3, 2015, 211 pounds of phosphorus were released from Pawtuckaway Lake during the early stages of the lake drawdown, compared to 1066 pounds in 2014 as a result of lower phosphorus concentrations and less water entering and leaving the lake. The volume released from the lake in 2015 was 37 percent of 2014’s volume, and the peak phosphorus concentration at Drowns Dam outlet in 2015 was 40.2 ug/L compared to 2014’s concentration. NHDES is looking into the reasons for lower phosphorus concentrations in the lake.

Wiswall Dam water use – Under the UNH/Durham Water System’s Instream Flow Program water management plan, UDWS must stop withdrawing water from the Lamprey River whenever flows at the USGS gage fall below 16 cfs.  UNH has developed a website at http://energy.sr.unh.edu/water/ which shows UDWS’s water withdrawals from Wiswall Reservoir and the reservoir levels.   The lake level drawdown for 2016/2016 target will be -5 feet (minus 5 feet).

Click here to read the full report (PDF):  2016-plia-article-from-des

Lake Host/Weed Watcher Training

SAVE THE DATE!
Combined Weed Watch and
Lake Host Training
Protect our Lake
All PLIA members are invited.
Conducted by
Therese Thompson
at
Nottingham’s Municipal Complex
Conference Room
Saturday May 14th 2016
9:00 am – 12:00 noon
Please let us know if you are coming by May 5, so we can have enough materials for each of you.

Steve and Peggy, Co-captains
Weed Watch Warriors W3
Home 603 895-6120      Steve’s Cell 603 568-3202