United States
Environmental Protection
Agency
Office of Water
Washington, D.C.
EPA832-F-99-011
September 1999
&EPA Storm Water
O&M Fact Sheet
Catch Basin Cleaning
DESCRIPTION
Catch basins are chambers or sumps, usually built
at the curb line, which allow surface water runoff to
enter the storm water conveyance system. Many
catch basins have a low area below the invert of the
outlet pipe intended to retain coarse sediment. By
trapping sediment, the catch basin prevents solids
from clogging the storm sewer and being washed
into receiving waters. Catch basins must be cleaned
periodically to maintain their ability to trap
sediment, and consequently their ability to prevent
flooding. The removal of sediment, decaying
debris, and highly polluted water from catch basins
has aesthetic and water quality benefits, including
reducing foul odors, reducing suspended solids, and
reducing the load of oxygen-demanding substances
that reach receiving waters.
APPLICABILITY
Catch basin cleaning should be performed at any
facility that has an on-site storm sewer system that
includes catch basins and manholes.
Although catch basin cleaning is easily
implemented, it is often overlooked in an overall
storm water management plan. In addition, many
of the catch basin cleaning programs that have been
implemented focus only on removal of debris from
grate openings; full implementation of the catch
basin cleaning BMP should also include removal of
debris from the catch basin itself.
ADVANTAGES AND DISADVANTAGES
Catch basin cleaning is an efficient and cost-
effective method for preventing the transport of
sediment and pollutants to receiving water bodies.
This improves both the aesthetics and the quality of
the receiving water body.
Limitations associated with cleaning catch basins
include:
• Catch basin debris usually contains
appreciable amounts of water and offensive
organic material which must be properly
disposed.
• Catch basins may be difficult to clean in
areas with poor accessibility and in areas
with traffic congestion and parking
problems.
• Cleaning is difficult during the winter when
snow and ice are present.
Sediment and debris removed from catch basins can
potentially be classified as hazardous waste. As a
result, the materials must be disposed in a proper
manner to avoid negative environmental impacts.
PERFORMANCE
Based on current data, it is not possible to quantify
the water quality benefits to receiving waters
resulting from catch basin cleaning. The rate at
which catch basins fill with debris, as well as the
total amount of material which can be removed by
different frequencies of cleaning, are highly
variable and cannot be readily predicted. Past
studies have estimated that typical catch basins
retain up to 57 percent of coarse solids and 17
percent of equivalent biological oxygen demand
(BOD).
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In addition, data collected as part of a Nationwide
Urban Runoff Program (NURP) project in Castro
Valley Creek, California, indicated that catch
basins, cleaned on an average of once every year
and a half, contained approximately 60 pounds of
material each at the time of the cleaning.
OPERATION AND MAINTENANCE
Catch basins should be inspected at least annually
to determine if they need to be cleaned. Typically,
a catch basin should be cleaned if the depth of
deposits is greater than or equal to one-third the
depth from the basin to the invert of the lowest pipe
or opening into or out of the basin. If a catch basin
significantly exceeds the one-third depth standard
during the annual inspection, then it should be
cleaned more frequently. If woody debris or trash
accumulates in a catch basin, then it should be
cleaned on at least a weekly basis.
Catch basins can be cleaned either manually or by
specially designed equipment. This equipment may
include bucket loaders and vacuum pumps.
Material removed from catch basins is usually
disposed in conventional landfills. Before any
materials can be disposed, it is necessary to perform
a detailed chemical analysis to determine if the
materials meet the EPA criteria for hazardous
waste. This will help determine how the materials
should be stored, treated, and disposed.
COSTS
Catch basin cleaning costs will vary depending
upon the method used, the required cleaning
frequency, the amount of debris removed, and
debris disposal costs.
Cleaning costs for catch basins were estimated in
three NURP program studies (Midwest Research
Institute, 1982). These estimates are summarized in
Table 1.
In communities equipped with vacuum street
sweepers, a cleaning cost of $8 per basin cleaned is
recommended for budgetary purposes (Southeastern
Wisconsin Regional Planning Commission, 1991.)
Cleaning catch basins manually costs
TABLE 1 CLEANING COST PER CATCH
BASIN
Location
Castro Valley,
CA
Salt Lake
County, UT
Winston-
Salem, NC
Method
Vacuum attached
to street sweeper
Vacuum attached
to street sweeper
Vacuum attached
to street sweeper
Cost
$7.70
$10.30
$6.30
Source: MRI, 1982.
approximately twice as much as cleaning the basins
with a vacuum attached to a sweeper. Therefore, a
cost estimate of $ 16 per catch basin cleaned may be
used for manual cleaning. It should be noted that
costs vary depending on local market conditions.
REFERENCES
1. Midwest Research Institute, 1982.
Collection of Economic Data from
Nationwide Urban Runoff Program
Projects-Final Report. Report to U.S.
Environmental Protection Agency.
2. Minnesota Pollution Control Agency, 1989.
Protecting Water Quality in Urban Areas.
3. Southeastern Wisconsin Regional Planning
Commission, 1991. Cost of Urban
Nonpoint Source Water Pollution Control
Measures, Technical Report No. 31.
4. U.S. EPA, 1983. Final Report of the
Nationwide Urban Runoff Program. EPA
841/583109.
5. U.S. EPA, 1977. Catch Basin Technology
Overview and Assessment. EPA-600/2-77-
051.
6. Washington State Department of Ecology,
1992. Storm Water Management Manual
for Puget Sound.
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ADDITIONAL INFORMATION
Alameda County, California
Jim Scanlin
Alameda Countywide Clean Water Program
951 Turner Court, Room 300
Hayward, CA 94545
King County, Washington
Dave Hancock
Department of Natural Resources, Water and Land
Resources Division, Drainage Services Section
700 5th Avenue, Suite 2200
Seattle, WA 98104
Salt Lake County, Utah
Terry Way
Salt Lake County Engineering Division
2001 South State Street, Suite N3300
Salt Lake City, UT 84190
Southeastern Wisconsin Regional Planning
Commission
Bob Biebel
916 N. East Avenue, P.O. Box 1607
Waukesha,WI53187
City of Winston Salem, North Carolina
Terry Cornett
Department of Public Works, Streets Division
P.O. Box 2511
Winston Salem, NC 27106
The mention of trade names or commercial
products does not constitute endorsement or
recommendation for the use by the U.S.
Environmental Protection Agency.
For more information contact:
Municipal Technology Branch
U.S. EPA
Mail Code 4204
401 MSt, S.W.
Washington, D.C., 20460
IMTB
Excellence in compliance through optimal technical solutions
MUNICIPAL TECHNOLOGY
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