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Spring Progress and Planning for the Restoration Project at the Bulfinch marsh
Tim Smith, Project Director
Notes - Friends of Alewife field trip - April 15, 2005
April 15 Site walk observations and task assignments
The project team convened around 9am at the Bullfinch parking lot to inspect the proposed project site and discuss locations for an array of hydrologic monitoring devices.
The basic consensus was that little or no flow occurs under Route 2. Culverts along Route 2 seem to be sized for roadway drainage only, not for passage of streamflow.
Preliminary observations seem to suggest that the majority of input into the project site comes from the small ditch/stream from Little Pond and run-off from the highway and developed lots along Route 2.
Need to investigate contribution of flow, in any, from north side of Route 2.
Staff Gauge Locations:
Flowmeters: David and students will measure flow volumes at four locations:
David and students will use multi-meter to collect several water quality parameters in conjunction with other data collection; DO, Temp, pH, conductivity, etc.
Regular sampling should occur one per week, starting ASAP. Effort should be made to capture data during relatively wet spring periods and relatively dry summer months. In addition to weekly sampling, extra sampling should be conducted during wet weather. Need to define "wet weather", ie sampling will occur within 4-8 hours after ¼" rain. Ideally, data will be collected during and after various types of rain events. Rainfall data should also be tracked. If possible, data collection should continue through the summer and fall.
Other Data Issues:
Vegetation - Mapping of general cover types using GPS should occur soon, before the site becomes overgrown and inaccessible. Once the general patterns are mapped, additional inventories could be conducted during the growing season to get more detailed data on species and abundances. Tim will coordinate with David on this.Task Summary:
Notes - Friends of Alewife field trip - April 15, 2005
The purpose of the field trip was to view the site and comment on monitoring well and staff gage sites. While walking around the perimeter of the marsh we also commented on various drainage inputs from Route 2 and Acorn Park Drive.
It was advised to obtain Route-2 road layout maps from Mass Highway that show the intersection of Acorn Park Drive. Drainage information and recorded elevations should be on these maps.
I spoke to our NRCS soil scientist, Bill Taylor, and he is ready to visit the site to classify the soils. Bill will wait to hear from whoever is coordinating this part of the project. Since we will again be on private property, could whoever is in charge of this part of the project also notify the land owner that we will be on-site and describe to him what we will be doing. Hand borings with an augur, no equipment. Bill can be reached as follows:
This area located just off Acorn Drive and just below the newly installed detention basin was described as a section of marsh that is relatively un-scathed and is an example of a condition to replicate elsewhere in the marsh.
This section of the marsh has open water year round and is home for a wide variety of marsh life. Note the transition from open water to cat-nine-tails to phragmities.
Several existing monitoring wells were located on our tour. The one in this photo is located along Route-2 just to the west of the closed former night club. It was mentioned that this might be a monitoring well established at the site of a former gas station. The well casing was 3 inch iron pipe. An approximate 1 inch diameter PVC tube is within the casing and appeared operable. There was another well located within the marsh to the southeast of this well. It was mentioned that a good site for installation of a new monitoring well would be within the marsh and approximately 200 feet to the south of the above well.
At the intersection of Route-2 and Acorn Park Drive there are a series of individual catch basins along Route-2 that outlet into a common channel. Each basin has its' own headwall structure. There is also another input into this system from a catch basin located in a grass swale between Route-2 and the Acorn Park Drive on ramp. We discussed contacting Mass Highway for discussions on the installation of water quality BMP's at this location.
This is the overflow channel from Little Pond located on the west side of Acorn Park Drive at its intersection with and along side the on ramp for Route-2. Both sides of the culvert under Acorn Park drive were under water at the time of the visit. It appeared that the culvert entrance on the east side of Acorn Park drive was silted in from material deposited by the catch basins outlets from Route-2. This area was discussed as a possible inflow source of water from Little Pond to the marsh. For this to occur: the flow from Little Pond would have to be managed; the culvert and channel would have to be cleaned; and the channel re-graded for this to happen.
The following photos were taken at Little Pond after the site visit:
The area to the lower right of the photo is the un-controlled outlet from Little Pond. A weir type control structure would have to be constructed at this location if the level of Little Pond were to be managed to achieve flow to the overflow channel to the culvert under Acorn Park Drive mentioned above. The location of the overflow channel entrance at Little Pond is shown in the upper portion of the photo.
The beginning of the Little River at the outlet of Little Pond. Flow is in the direction of the arrow.
A major factor when considering a control structure and the possibility of raising the level of Little Pond is the amount of development at low elevations around the Pond. With this in mind the overflow channel may need to be graded to match the elevation of the natural pond outlet. A control structure could then be installed at the channel culvert entrance at Acorn Park drive.