Long Term Community Plan 2012-2022 - Hurunui District Council

www.hurunui.govt.nz
Activity 1: Sewerage
Overview
The Sewerage activity includes the various functions of the
seven sewerage schemes in the District.
Current Situation
The district operates 7 separate sewerage schemes, serving all
but 4 urban localities. All use oxidation ponds for treatment of
sewage and 14 pump stations are operated within the pipework.
Table 1, sets out the number of connections each sewerage
scheme services.
1. The current situation for each of the sewerage schemes
is outlined below:
2. Amberley: Reticulation was installed between 1974
and 1977 with a staged multi-pond treatment and land
disposal onto pasture (free draining sandy soil) adjacent
to the coast.
3. Cheviot: Reticulation and aeration tank was installed in
1964, upgraded to single oxidation pond plus borderdyke
disposal in 1982 and further improved in 1999/00
to a multi-pond facility with spray irrigation to pasture
and overland flow polishing prior to discharge to
adjacent waterway when the irrigation area is saturated.
4. Greta Valley: Reticulation and treatment/disposal
facility was installed in 1979 for a Council funded
subdivision with one pond treatment and disposal to
land (travelling irrigator) or to nearby waterway when
the soil conditions are too wet for irrigating.
5. Motunau Beach: Reticulation, treatment and disposal
area was installed in 1987 in response to meet
community and public health expectations, using a dual
pond for treatment (with aeration) and land based
discharge onto pasture (private title) with border dyke
application.
6. Hanmer Springs: Reticulation was installed 1971 with
dual pond treatment and discharge to the Chatterton
River, replacing the older reticulation and settling tank
(installed in 1949 in the hospital property) which was
not meeting local expectations. A further upgrade
including additional ponds and aerators was completed
in 2007/08.
7. Hawarden: Reticulation and treatment/disposal facility
was installed in 1966 with twin ponds and overflow to
an open drain.
8. Waikari: Reticulation and treatment/disposal facility
was installed in 1967 with twin ponds and overflow to
the Waikari River with discharge altered to land disposal
via spray in 1996 on an adjacent farmland. It has been
further upgraded in 2005 with an additional pond and
an increased effluent disposal area.
Recently, we investigated the feasibility of two new sewerage
schemes for Culverden and Waipara. Public feedback on the
results, and particularly the cost of the building the schemes was
not favourable. There clearly is the sentiment “don’t fix what’s
not broken”,therefore, reticulated schemes for Culverden and
Waipara are not planned at this stage. Should there be any
changes in legislation or adverse effects to groundwater are
noted (in terms of effluent contamination), then this democratic
approach will be revisited for alternative consideration.
The levels of service for our sewerage schemes can be found
in the appendices section of this plan. These levels of service
are monitored internally and will not be reported in the Annual
Report.
Table 1: Sewerage Connections
Scheme
Active
Connections
Undeveloped
Sites (half
connections)
Pan Connection
Equivalents
(includes multiple
pans)
Amberley 1,042 106 1,350
Leithfield 172 25 203
Cheviot 208 8 328
Greta Valley 28 12 59
Motunau Beach 119 18 137
Hanmer Springs
1114 293 1,923
Hawarden 120 11 169
Plans for the future
New pipelines in Amberley are to be built. Plant renewals will
be undertaken as identified in our Activity Management Plan
for wastewater.
We have an ‘Assessment of Water and Sanitary Services”. This
assessment will be reviewed from time to time during the life
of this plan and is due for its next review in the 2013/14 year.
Works associated with current resource consent requirements
for Hanmer Springs and Cheviot wastewater treatment plants
requires us to look towards disposal to land as alternative
adopted approaches to disposal to waterways (by 2014/15).
Hanmer Springs wastewater treatment plant ponds exhibited
seasonally low dissolved oxygen (DO) levels, which could result
in odour problems to nearby residential properties (dependent
upon the prevailing wind at the time). Aerator upgrades will be
required to eliminate this potential problem and ensure that
council remains within the tolerated minimum acceptable values
for DO.
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