Conservation Commission Great Bog Trip Notes – Draft 5/20/09
On 5/19/09 Pat Barkman, George Ferguson, and Joe Hovious of the Newtown Conservation Commission met with George Benson (Director, Newtown Land use) and Bob Eckenrode (President Newtown Forest Association) to view the dam and current conditions at the Great Bog on Boggs Hill Road. Pat, George F and Joe kayaked or canoed in the pond to view conditions from the water and get some data and pictures. George Benson brought instruments to measure dissolved oxygen, temperature, and turbidity in the pond water. Joe, George Ferguson, and Bob Eckenrode walked the eastern edge of the pond. Joe and George visually observed the western area of the Bogg along both sides of Key Rock road and observed wet swampy or boggy conditions. George Ferguson and Joe attempted to find access
to walk the northern boundary off Sweet Meadow Road, but this will require permission of the handover or wading through heavy swamp thickets from the access point of the Forest Associations property on 302. Caraleigh Wilson may be able to provide some guidance here. The following are observations and recommendations based on this trip.
Observations
· We observed numerous fish, a great blue heron, Canada geese, ducks, shore birds such as red winged blackbirds, and amphibians such as frogs and turtles in and around the pond.
· There was limited or inconclusive evidence of current beaver activity. The only possible activity was an earthen dam between a pond adjacent to the Bogg that was observed by Hovious, Eckenrode and Ferguson.
· The maximum pond depth observed is currently about 2 ft. extending from the dam for about 100 yards and not covering an extensive area. Most of the area reachable by canoe or kayak was very shallow.
· The current water level is down approximately 18 inches from past levels based on markings on trees and other vegetation
· The water level will continue to drop as flow out of the pond continues. This provides a limited window to bring pond level up this season. An estimated additional 6-8 inches is expected as the water nears the level of the outlet structure and leaks through the dam structure.
· At 1:45 pm the oxygen level was ~8.6 mg/l and the temperature was 19.2 C.
· Turbidity levels were as follows: open area 6, near outlet 3, outlet side of dam 0.8. Water was colored from tannins in the bog.
Conservation Commission Recommendations
1. Raise the pond level 12 inches before the dry season.
2. Install a staff gauge in the pond to accurately measure pond water level. Keep a record during the summer to evaluate impacts.
3. Run a series of levels that relate the outlet structure height to needed freeboard for the road.
4. Conduct a drainage assessment for the watershed behind the dam to evaluate potential flows.
5. Raise or otherwise modify the outlet structure to provide at least an additional 12 inches of water depth in the pond (consistent with the need for freeboard). This might be done without draining the pond through use of a V notch weir in the pipes outlets or a temporary coffer dam or plugging the pipes while raising the outlet ends.
6. Walk the rear of the bog area to examine possible damage in this area due to low water levels.
7. Establish an operating agreement and a communications program between DPW and Land Use to ensure that similar incidents impacting Newtown’s natural resources do not occur in the future. If the situation cannot be ameliorated quickly through cooperative means, enforcement action should be considered by Land Use staff and the Inland Wetlands Commission.
| 
