Norfolk County
WATER MANAGEMENT PROGRAM INFORMATION
Currently 25 towns belong to the Norfolk County Mosquito Control Project. Along with adulticiding and larviciding practices, the NCMCP also offers a Water Management Program. This program consists of clearing existing drainage ditches of debris in order to eliminate standing water, thus reducing mosquito breeding. In many cases such work can reduce the amount of insecticides the Project has to use in order to reduce the nuisance population of mosquitoes in the surrounding area. We refer to this type of work as source reduction work and consider such work to be an important part of an Integrated Pest Management (IPM) strategy (go to IPM link for more info). Data collection and surveillance measures are important elements of any mosquito IPM strategy. Data collected during insecticide applications is used to aid in the determination of future Water Management Project sites.
Ditches are cleaned either by hand or through the use of excavators. Hand Cleaning is accomplished through using shovels, clam rakes, chainsaws, brush cutters and a variety of other hand-held instruments (see photo).
The NCMCP utilizes three wide-tracked low ground pressure excavators in order to clear ditches in which hand cleaning would not be effective due to years of neglect (see photos).
The Project becomes aware of possible water management projects through resident or town official requests/complaints, NCMCP field technician/ employee observations, or through investigation of past projects. The Water Management Project Coordinator then investigates the site to see if the area will benefit through drainage restoration.
Picture prior to excavation: 
Same site immediately after excavation: 
Norfolk County Mosquito Control Project uses the following set of guidelines for conducting Water Management Project:
GUIDELINES FOR WATER MANAGEMENT INVESTIGATIONS
I. SITE SELECTION- From one or more of the sources listed. The source of each site selected will be recorded with the site plan and issued a number.
A. NCMCP files on larviciding sites.
B. Field personnel's observation.
C. Investigation of residents' request/complaints.
D. Investigation of public officials request/complaints.
II. SITE HISTORY - A history of ditch maintenance must be reasonably evident from one or more of the sources listed.
A. Physical evidence- such as spoil deposits, soil profile, tree stumps, structures, etc.,
B. Historical evidence such as municipal, state or mosquito control- records or maps. Recollection of residents, abutters, officials, etc.
III. BREEDING HISTORY OR POTENTIAL - A history of mosquito breeding or significant potential of mosquito breeding which may impact a human population must be evident from one or more of the sources listed.
A. Larviciding site records.
B. Field Personnel's observations
C. Residents/public officials' complaints
D. An existing condition which in the judgment of the mosquito control superintendent may cause mosquito breeding to a degree which will have a significant impact on a human population,
IV. SITE PLAN - A survey to establish preexisting site conditions and plan of proposed ditch maintenance activities.
A. Photographic record - From numerous pre-chosen, fully recoverable stations.
B. Site map - A copy of an assessors, topographical, or aerial photograph indicating area of proposed ditch maintenance, access and egress.
C. Ditch Type - An indication of the type of ditch such as Main Ditch, Lateral Ditch, or Sub Lateral Ditch (see legend).
D. Wetland type - A brief general description such as, Maple swamp, low branch swamp, grassy swamp, etc.
E. Preexisting ditch profile: - A profile of preexisting ditch condition such as length, depth, bottom and top width, side slope and spoil deposits, etc..
F. Cause and effect - A brief narrative description of the cause and effect of the problem or potential problem associated with the need for the ditch maintenance project.
G. Site plan profile - A profile of the Planned ditch maintenance project including length, depth, bottom and top width, side slope, cubic feet of spoil displaced.
H. Soils profile - Take and record a minimum of one core sample per 100 linear feet of ditch bottom to determine percentages of minerals and organics to be excavated.
V. PROPERTY OWNERS PERMISSION - Secure written permission from property owner/s or person/s (Trustee/s) legally in control of property prior to starting work on site. Standard permission form will provide purpose and brief description of project and any mutually agreed upon conditions. Verbal consent may be acceptable on properties with drainage easements and otherwise on a limit basis provided all parties are in agreement.
VI. NOTIFICATION - Notify property owners, abutters (were applicable), appropriate authorities and/or agencies and post site thirty days in advance of starting work and supply with the following:
A. Notification form - Standard form.
B. Site map - A copy of an assessor's or topographical map or an aerial photograph indicating the area of proposed ditch maintenance.
C. Site Profiles - Soils, wetlands, dimensions, etc.
AGENCIES TO NOTIFY:
1. Municipal Conservation Commission
2. Massachusetts Department of Environmental
Protection, Division of Wetlands and Waterways
3. Natural Heritage Endangered Species Program
4. U.S. Army Corp of Engineers
5. Dig Safe.
6. Local Departments of Public Works (where applicable)
FOLLOW UP NOTIFICATION - If for whatever reason work on a site does not begin within sixty days of the initial notification a reasonable effort shall be made to give informal notice prior to or on the day site work begins to the following:
1. Municipal Conservation Commission.
2. Property Owner/s.
3. Review Dig Safe number or re-notify as applicable.
VII. SITE WORK - All on site work will conform to the following criteria.
A. Site - A site will not result in a cumulative loss of more than 5,000 square feet of bordering vegetated wetlands (BVW). A site will not be in area of outstanding Resource Waters, Area of Critical Concern or in endangered species areas without prior approval or agreement.
B. Access/egress - It may be necessary to clear a path to transport equipment and personnel to and from a site. Routes of access and egress will be chosen to minimize impact. Cleared brush may be place on the path as a mat.
C. Site prep / brushing - The clearing of brush will not exceed twenty (20) feet on either side of the ditch. Cut brush will be neatly stacked beyond the range of spoil deposition, chipped or removed from the site. Spoil deposited on brush will be minimized. Only those trees and brush that may impede the flow of water, operation and safety of equipment and personnel will be cut.
D. Excavations - As much as possible, a ditch will be excavated to conform to it's original or previously maintained dimension and coarse as indicated by the existing physical conditions of the ditch and site and the historical perspective of residents, abutters, municipal and/or state officials … etc.
In the event this is not feasible a ditch will be excavated to confirm to the greater volume and velocity of water.
E. Excavator - Excavation will be done by means of suitable low ground pressure tracked vehicle not to exceed three pounds per square inch (3. PSI).
F. Ditch bottom - the grade and depth of the ditch bottom will not exceed the previously established grade. In the absence of an established grade the ditch bottom grade will be determined by the depth necessary to achieve sufficient flow not to exceed bottom grade of the nearest down stream discharge.
G. Down stream - Excavation will begin or end at a point of adequate discharge.
H. Spoil - Whenever possible excavated spoils will be deposited off the wetland onto an immediately adjacent upland edge and graded. Spoils deposited on a wetland will be spread as thinly and evenly as possible, the optimum not to exceed a depth of six inches above grade on alternating banks of the ditch so as not to impede lateral flow. Deposition of naturally occurring mineral spoils will be kept to a minimum but should not to exceed 30% of the total spoil displaced. When conditions dictate spoils be deposited on one side of the ditch only, spoils will be randomly breached at appropriate intervals to promote lateral flow.
I. Road Sand Run off - whenever possible road sand run off will be deposited off the wetland or removed from the site.
VIII. POST MONITORING - All completed ditch maintenance projects will be inspected immediately upon completion and randomly monitored for a period not to exceed two (2) years to insure the desired results are attained and no significant adverse impact occurs as a direct result of ditch maintenance activities and make all necessary and reasonable adjustment and or corrections.
A. Ditch bottom Profile - Establish and record the grade of the ditch bottom for future reference.
B. Mosquito breeding - randomly check for mosquito breeding
C. Vegetation - observe vegetation recovery in areas of spoil disposition and general site impact.
D. Ditch - observe stabilization and condition of ditch.
E. Photographic record - from numerous pre-chosen, fully recoverable stations once annually for two consecutive years during period of peak vegetation.
F. Site review - Periodically review the site to observe current conditions and record any problems that may impede the flow of water or cause negative impact and report to appropriate authority.
Currently, the NCMCP is working closely with the Army Corps. Of Engineers in order to establish the proper set of guidelines to follow in conducting ditch maintenance work. In addition to the above guidelines, we have our site visits with the Army Corps of Engineers:
The chosen work site must have been previously existing and maintained prior to July 1, 1977 (Clean Waters Act), or a proper permit must have been obtained.
The NCMCP must have adequate proof/information in the files showing the area was previously maintained or permitted.
If the NCMCP needs a determination on a particular site, we will notify the Corps, send them an 8 ½" X 11" site plan, and they will provide a verification of maintenance upon visitation and approval.
Post-Monitoring of past Water Management Sites is also an integral part of our program. The photographic records aid us in the development of future ditch maintenance procedures and allow us to track the recovery time of a particular site. All sites are data based and visit dates are recorded, as well as any hand cleaning work performed or mosquito breeding data. Such information enables the NCMCP to track the efficacy of our Water Management Work and allows for the prevention of possible mosquito breeding sites.
After an excavation is complete, NCMCP Field Technicians routinely hand clean the ditch in order to prevent any blockages from causing flooding or breeding problems. This also allows the ditch to remain functional for longer periods of time without having to re-excavate. The NCMCP will continually improve upon its Water Management Practices and Program in order to provide an efficient service with low-level environmental impacts.
Please feel free to contact NCMCP with any Water Management requests or for further information about our program.