HomeMy WebLinkAboutWD-83-80 %V
TOWN OF NEWCASTLE PUBLIC WORKS DEPARTMENT
Director's Report to Public Works Committee.
ITEM: WD-83-80.
DATE: June 17, 1980.
SUBJECT: Storm Drainage.
Cean Investments Subdivision.
BACKGROUND:
In August of 1975 Cean Investments Limited made application for a
Plan of Subdivision on lands lying north of the C.P.R. tracks and
east of High Street in Bowmanville. The subdivision has not pro-
ceeded, to date, due to the lack of water and sanitary treatment
facilities in Bowmanville.
In 1979, preliminary Engineering Drawings were presented to the
Public Works Department detailing the proposed servicing of the
site, including the provision of a storm drainage channel, from
the north limit of the C.P.R. lands to the existing storm sewer
on Liberty Street.
The Developer's Consultant, his Engineer and Works Staff met on
several occasions to discuss the matter of storm drainage, with
the major emphasis being placed on the open channel outfall pro-
posal by the Developer, as opposed to that of a piped storm
sewer as proposed by the Town.
Prior to 1973, the total watershed draining southerly to the C.P.R.
property was comprised of approximately 100 acres, the major flows
being via:
(a) storm sewers situated on some of the resident-
ial streets (High Street) .
(b) ditches, either along the residential streets
of along the north limit of the C.P.R. line.
(c) a major open channel which commenced in the
area of (the present) Vanstone Court and proc-
eeded, southerly, through several read yards
(Sunset Road, Somerfield Drive, Third Street)
to Third Street, then southerly through more
rear yards to the north limit of the C.P.R.
property. At this point the open channel
picked up the flows from the entire watershed ,� v.,
area and, by means of a 24" diameter culvert W
crossed the C.P.R. line and continued south-
/ 2 . . .
i
WD-83-80 (2)
(c) -erly, by open ditch, to Liberty Street where
it then entered the storm sewer running along
the east boulevard of Liberty Street to
Concession Street.
In 1973, two subdivision proposals were approved, namely:
(i) Vanstone Court.
(ii) Meadowview Boulevard & Sunnicrest Boulevard.
At the time of development a storm drainage outfall proposal was
presented to the Town for the drainage of the above subdivisions
through the major open channel but, due to concerns of residents
in the area and the unavailability of easements, the proposal was
rejected and a storm sewer was constructed to the east, towards
Liberty Street, to an outfall east of Liberty Street. This plan
eliminated approximately 29.5 acres of lands from the total water-
shed area draining to the culvert under the C.P.R. railway, thus
leaving approximately 70 acres to be accommodated.
The area between Third Street, the C.P.R. property and Liberty
Street is presently in a very poor condition, with the lands un-
suitably drained they have gradually built up with silt and debris
and have become overgrown with weeds and trees.
REPORT:
The Developer's proposal for storm drainage of the subdivision
under discussion is to outfall at the south-easterly corner of the
development; the drainage would then flow, via an open channel, to
the 24" diameter culvert under the D.P.R. line and then southerly
across the property owned by Mr. L. Welsh (all via open channel)
and then would be collected into the 30" diameter storm sewer which
crosses Liberty Street and continues southerly.
The Public Works Department felt that, to improve the present
deficiencies in the storm drainage facilities, a piped storm sewer
system, using the existing facilities wherever possible, would not
only improve the storm drainage but would enhance the residential
area. Maintenance costs would be dramatically reduced as compared
to those which are associated with open channel systems.
For the foregoing reasons, this Department requested the Developer
to install a storm sewer from his subdivision to the culvert which
crosses under the C.P. Railway which, at this point, would pick up
the existing open channel runoff and the ditches along the C.P.
Railway line. The storm sewer would then connect into the existing
system on Liberty Street which has sufficient capacity to handle
the flows generated.
/ 3 . . .
WD-83-80 (3)
The Developer would be required to obtain an easement from Mr.
Welsh, for the construction of the storm sewer as proposed by the
Town, but would also require an easement if the storm drainage
was to be by open channel.
In many previous Subdivision Agreements, Schedule 'G' ("Works
Required") stipulating requirements of the Developer, in re-
lation to storm drainage and other facilities, contains the foll-
owing clause:
"The Owner shall construct, install, supervise
and maintain a complete storm drainage system,
for the removal of upstream storm water and
storm water originating within the Developer's
lands. . . as may be required in accordance with
the Town of Newcastle's Design Criteria and
Standard Drawings".
Section 7:04 ("Storm Drainage") of the Town's Design Criteria,
further states:
"Open Channels shall only be considered at the
discretion of the Director of Public Works, when
the design flow exceeds 500 c.f.s."
The design flow from the previously discussed watershed area is
approximately 20 c.f.s. , and, thus, is far below the Town's
standard.
In the Draft Plan of Conditions for this Subdivision it is pro-
posed that the Developer grants to the Town a block of lands along
the C.P.R. allowance. This will act as a buffer between the rail-
way and the proposed Subdivision. The block is to be landscaped
and graded, to the satisfaction of the Town. This block which is
to be dedicated, abuts the lands on which the watercourse is
situated and will, in all probability, be used by the residents
of the Subdivision.
I
With the above in mind, the Public Works Department felt that an
open channel through the area would be a liability to the Town.
RECOMMENDATION:
THAT storm drainage, within the Cean Investments
proposal and/or the immediate watershed area, be
accommodated by means of a storm sewer and, further,
that this shall become part of a Developer's Agree-
ment.
i
I
JF:vh