Monday, October 29, 2001

  

SCOPE OF SERVICES

 

Watershed Assessment

 

Larson Design Group, Inc. (LDG) will complete a watershed assessment of the Choconut Creek Watershed within Pennsylvania.  Components of the assessment will include analysis of stream channel geomorphic condition, riparian wetlands, water quality, land use, storm water management, and stream temperature/canopy cover.  Recommendations for future actions will be made as part of the watershed assessment report.  This information is gathered through field investigations, aerial photographs, and existing mapping.  Field data will be collected on stream health (see below), habitat quality, canopy health, bank erosion, and water quality.  Supporting information will be drawn from soil maps, land use maps, and other existing data.  Specific components of the watershed assessment are described below. 

 

Access

 

Choconut Creek Watershed Association (CCWA) and Choconut Township (CT) will be responsible for securing access to Choconut Creek for LDG personnel while they are conducting the assessment.

 

Geomorphic Data

 

High-resolution (less than 1m horizontal error) Global Positioning System (GPS) will be used by a trained fluvial geomorphologist to map key features and characteristics of the stream channel network.  The GPS data will be incorporated into GIS in either AvStreams format or LDG’s geomorphic assessment format.  A detailed map of the geomorphic condition of the stream provides the context necessary to conduct natural channel design and stream channel restoration within the watershed.  This data will be collected in conjunction with the Rosgen Level II classification data listed below.

 

LDG will collect Rosgen Level II classification on 14 stream reaches throughout the 14 miles of stream channel to be assessed. 

Data collection for Level II classification of 14 stream reaches includes the following: 

Bank Full Width

Bank Full Depth

Flood Prone Width (@ 2X Bank Full Depth)

Meander Wavelength

Meander Amplitude

Length

Slope (Water Surface and Channel Bed)

Bed Features

Particle Size Distribution

Pool/Riffle Ratio

These measurements will be used to compute entrenchment ratio, meander width ratio, width-depth ratio, and dominant channel substrate in addition to be used to classify the stream in the Rosgen Stream Classification.  This Level II survey information also provides information that is useful in determining the evolutionary state of the channel. 

 

Data for future storm water management planning

 

LDG will survey hydraulic dimensions of the 17 bridges or culverts and 11 pond/lake outlets that influence the hydrology of Choconut Creek.  This data will be provided in tabular format to the CCWA/CT.  The vertical datum for this survey will be assumed. 

 

GIS

 

GIS mapping and analysis will be conducted using applicable ESRI software.  LDG maintains a GIS database of data necessary for watershed assessment and analysis. 

LDG will transfer GPS data from the channel assessment to a GIS format agreed upon with CCWA/CT.  

 

With the final assessment report, laminated map sheets of at a maximum scale of 1:24,000 will be included.  Maps of geomorphic form and problem areas, habitat quality, and an overall watershed reference map will be provided for a total for 3 maps. 

 

Water Quality

 

Quarterly water quality samples at three locations will be collected and analyzed for temperature, pH, alkalinity, turbidity, specific conductivity, nitrates, phosphates, and dissolved oxygen.  Metals to include total aluminum, total calcium, total copper, total iron, total magnesium, total manganese, total nickel, and total lead will be measured once at each of three locations during the grant period.  Water quality samples collected for metals analysis will be conducted using the EPA accepted USGS micro-gram per liter sampling protocol.  This sampling protocol provides assurances that contamination is not introduced into the samples that will be analyzed for very low concentrations of contaminants. 

 

LDG personnel will complete typical field parameters, pH, specific conductivity, temperature, and dissolved oxygen.  An EPA certified water quality laboratory would complete all other analysis. 

 

Quality assurance samples for the routine water quality samples including both blanks and replicate samples will compose 10 percent or 3 samples.  Collection of quality assurance data validates the data collected throughout the study cycle. 

 

Macro-invertebrates will be collected and analyzed one time during the assessment period at 6 locations throughout the watershed.  These locations should be representative of the watershed and will be chosen in consultation with the watershed association

 

Wetland Study

 

The wetland study will be conducted to locate wetlands or prior converted wetland areas that have significant potential to reduce peak flows on Choconut Creek.  Significant areas will be mapped and prioritized based on potential for flow impact, feasibility, and funding options.  LDG will make recommendations for funding sources to support wetland restoration specified in the prioritized plan.  

 

Land Use Recommendations

 

Land use recommendations will be made as a part of the overall watershed assessment.  These recommendations will be made based on water quality, riparian health, stormwater management, and in-stream habitat.  Potential locations for land use improvements, especially those in direct contact with the stream will be mapped. 

 

 

Reclassification of Stream

 

LDG will conduct continuous temperature monitoring from Spring 2002 until the final water quality sample is collected in September 2003.  A minimum of two recording temperature monitors will be located in Choconut Creek.  These monitors will record temperature at least four times daily. 

Canopy cover data collected during the watershed assessment will be used to illustrate good canopy cover and/or target areas where riparian restoration and improved canopy cover may help to lower water temperatures. 

 

Advisory Group Meetings

 

LDG will participate in advisory group meetings up to a maximum of three additional meetings as needed through the grant cycle.  These meetings are in addition to the project kickoff meeting, three review meetings, and a final report meeting.   The total number of meetings included within this budget is eight meetings, which allows for quarterly meetings through the grant period.  It may be necessary to conduct more meetings early in the project and fewer during the second year as water quality monitoring will be the only continuing work.  

 

Reports

 

LDG will transmit 15 bound copies of the final assessment report to CCWA/CT.  Two compact disc sets of the final assessment report, GIS data, digital photographs, and water quality data will be transmitted to CCWA/CT.