HomeMy WebLinkAboutItem 05.cPositioned to Thrive
•
Lake viint
Public Works
February 2013
• Salt Storage
LAKEVILLE PUBLIC WORKS
Christopher Petree, Director
February 2013
Salt and treated salt are the
number one deicers for many
communities throughout the state,
as well as the Minnesota
Department of Transportation.
Previously many of these entities,
including Lakeville, used a salt and
sand mixture to clear the roads and
provide some additional traction.
Unfortunately, the sand didn't
really improve traction and
collected in the storm sewer
system and the small amount of
salt didn't do much to melt snow and ice. The
switchover to all salt as a deicer has really
focused on getting to the asphalt as fast as
possible to provide motorists a safer driving
surface. This, in turn, has prompted concerns
over increased chloride levels in the local
watershed. A focus area is salt handling and
storage since concentrations of salt are much
higher around a storage area and there is the
potential for salt spills when trucks are loaded.
This presents more of a problem during years
with mild winters since storage facilities may
contain significant amounts of salt when
spring rains arrive. Good housekeeping and a
well- designed storage facility play an important part in reducing chloride runoff.
Recognizing this problem, the Streets Division recently took steps to improve the
storage and handling of its own salt. Borrowing a material stacker from Dakota
1
County, salt was better placed to take advantage of space available in the facility,
trucks Toad inside the facility or close to the entrance to minimize spills and
spreading of salt, and spills are cleaned up before they become a problem. On the
road, each truck's salt spreader is calibrated to use the right amount of salt based
on road conditions and vehicle speed. This limits the amount of salt used and
reduces potential impacts to the local watershed.
❖ Sanitary Sewer Repair
Two pieces of equipment are
important in the process of
cleaning Lakeville's sanitary sewer
system; one is the sewer camera
and the other is the Vactor.
Procedurally, the Utilities Division
sends the camera through the
sewer main to locate and record
problem areas and to see what
needs to be cleaned; the Vactor
follows up and either cleans the
sewer with high pressure water or
removes any obstructions.
Periodically, the camera finds a crack or
small break in a pipe that can be repaired
by lining that section of pipe. However, it
was surprising to find a section of pipe
with a hole through it caused by the
placement of a gas line. The hole was
caused by directional horizontal boring, a
common technique in the installation of
utilities that doesn't require open
trenching. A gas line within a sewer line is
extremely dangerous should the gas line
leak. Staff notified CenterPoint Energy,
who uncovered the sewer line, moved
their gas line, and contracted for the repair
of the broken section of pipe. The Utilities
Division monitored the repair and had the Vactor out
hole before it was filled in.
to remove
liquids from the
2
• Clearing Boulevards and Sidewalks
Boulevards are typically
used to store snow during
the winter season. As snow
accumulates, snow on the
boulevard is benched back
to make room for the next
snowfall. Sometimes the
process of benching the
boulevard dumps the snow
on the adjacent trail,
requiring that the trail be
cleaned as well. This
winter, the rain events
followed by accumulating
snow created ice ridges on
the boulevards that required extra force to remove and made trails difficult to
clear. The Streets Division has had crews out recently to remove the ice ridges
from the boulevards and clear trails in preparation for the next snow event. By
doing this, it will make it easier for plows to move snow to the boulevards and for
staff to clear adjacent trails.
3