Drainage problems in the Lloyd Park the
play area
Friends of Lloyd Park report January 2013
There are several drainage problems evident in and around
the play area. They may have different
causes and therefore they may have different solutions. Action is planned on all areas.
1.
General
muddiness of the ground surface.
Failure of water to drain away on open ground is usually
caused by compacted soil. It is very
likely that the soil in the play area is compacted because there were heavy vehicle
movements and storage of building materials on it for a protracted period while
the works to the park and buildings were carried out. Compacted soil usually improves in a few
years because of the action of worms, frost etc. but this cannot be completely
guaranteed.
Action to date.
LBWF officers are seeking to establish if the poor
surface drainage in the play area is a case of compacted soil or if the area is
naturally marshy and therefore land drains should have been included in the
original design. If it were the latter, then
a case of professional negligence could be made against the landscape
architects on the scheme in order to fund the retrofitting of land drains. Two
trial holes have been dug in the play area – one filled with water and one did
not.
Further action under consideration.
Additional trial holes could be dug in order to gain more
information about the ground conditions.
If it were necessary to install drains then it would be necessary to
close the play area while the work was carried out. This would be carried out during autumn and
winter months in order to avoid the time when the playground is most used. Invasive work of this sort will not start
during this current winter.
It may be possible to encourage the surface water to soak
away by perforating the top layer of compacted soil. The soil under the playground is clay and was
not contaminated, therefore it would be safe to spear through the surface layer
by 300-400mm at intervals across the worst affected parts of the play area with
the intention aerating the soil and creating a path for water to flow down into
looser layers of ground below the surface.
This could be done through the holes in the existing flexible play
surface. Sarah Reid is going to consult
LBWF Highway Dept. engineers on this proposal.
If it is agreed then action could be taken immediately.
2.
Puddles
around the skate park and on the north side of the spoil mound.
The South West corner of Aveling Fields was always a boggy
part of the park. The new landscaped
spoil mound in that location appears to be squeezing water out to the edges of
the mound so that large puddles are created.
It is possible the soil around the skate park and the mound are also
suffering from compaction.
Action under consideration.
This area is being kept under observation, at least for
the rest of this season and perhaps longer.
If the puddles are persistent then the area will be planted with plants
and trees that thrive in moist conditions.
3.
Level
of water in the attenuation pond.
The purpose of the attenuation pond is to receive and
hold the rainwater from the roofs of the
Aveling Centre for a while so that the additional water running off the new
building does not flood the local drainage system. It was also intended as a surface soak-away
for the boggiest part of the park.
Action planned
The normal level of water in the pond is lower than it
was but is still higher than intended.
The contractors for the works to the park, Jerram Falkus, will be
returning to improve the drainage rate of the pond. When the drainage is satisfactory, the area
will be suitably planted.
4.
Water
collecting under the trampoline.
A drain should have been installed under the trampoline.
Its omission has been noted and Jerram Falkus are obliged to rectify the defect
under the terms of their contract with LBWF.
They have already been asked to do this and they will be asked again so
that the problem is rectified this winter.
