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4 Claremont Water Supply

4.1 Scheme Summary

Description		Quantity
Estimated Population Served		163
Scheme Coverage (1 Jan 2018)	Full Charges	54
	Half Charges	0
	>1 Charges	5
System Components	Bores/Intakes (No.)	1
	Treatment/Disinfection	1
	Reservoirs (No.)	1
	Pump Stations (No.)	1
	Piped (m)	2,687
History	Original scheme installation date	2005
Value ($)	Replacement Cost	$687,006
Value ($)	Depreciated Replacement Cost	$472,185
Financial	Operator cost (scheduled and reactive maintenance) per connection	$700.95/connection
Demand (m³) (1 Jan – 31 Dec 2020)	Average daily (m³/day)	153
	Peak daily (m³/day)	518
	Minimum daily (m³/day)	-
	Average daily per connection (m³/day)	2.4
Type of Supply		High pressure and unrestricted
Target Pressure & Flow at boundary	Pressure	>310 kPa
Target Pressure & Flow at boundary	Flow	>20 L/min
Sustainability	Well Security	Secure

4.2 Key Issues

The following key issues are associated with the Claremont water supply. A list of district wide issues are located in 5Waters Activity Management Plan: Volume 1.

Table 4‑1 Claremont Scheme Issues

What's the Problem	What we plan to do
Confirmation of compliance with New Zealand Fire Fighting Code of Practice compliance issues.	Council will investigate and recommend the approach in relation to any New Zealand Fire Fighting Code of Practice compliance issues.
Catchment management	To encompass a holistic view of the drinking water supply improved liaison with ECan and study of groundwater quality within the water supply protection zones are being investigated.

4.3 Overview & History

The Claremont Water Supply provides treated groundwater to a residential subdivision located on the south side of Main South Road, near Templeton. There are 59 sections within the subdivision, all of which are metered. Two backflow prevention devices are present within the scheme located at the two wastewater pump stations within the scheme.

The water supply for the subdivision was commissioned in 2005. Templeton is served by water from the Christchurch City Council supply. However, the Claremont subdivision is outside of the city boundary and therefore required a standalone supply. There is potential for the Claremont scheme to be connected to the Prebbleton supply (4 km away) in the future if the cost of supplying water from Prebbleton becomes more affordable than operating and maintaining the current supply.

Water for the Claremont water supply is obtained from a single deep bore off Devine Drive. The bore is 200 mm in diameter and 108 m deep. The water has been age tested to verify the potential secure status of the bore. Residence time results and subsequent sampling, combined with a physical inspection of the bore head, have led to the District Health Board (DHB) designating the Claremont bore as secure to date.

A single bore pump delivers water through the water treatment plant (WTP) where it is UV treated prior to being stored in a 110 m³ reservoir. The water is then boosted through three surface pumps to the reticulation. The scheme was designed as a high pressure, unrestricted metered supply. The booster pumps are controlled by a pressure sensor. When the pressure drops then either one or both of the smaller booster pumps start. If the pressure continues to drop, the larger fixed speed booster pumps is called to run. The smaller booster pumps continue to run. If the reservoir level becomes low, the bore pump is started, refilling the reservoir. The control system is linked to the Council’s Supervisory Control and Data Acquisition (SCADA) system and all inputs are powered by mains electricity. The SCADA system monitors the pumps, inflow into the reticulation, and reservoir level, recording among other things, daily water usage and pump hours. Alarms include pump fault and communications failure. The telemetry system has battery backup.

Figure 4-1
Claremont Water - Scheme map
Open larger map: 'Water Scheme'

Figure 4‑2 Scheme Schematic

4.4 System Capacity

This water supply was developed to serve the 59 lot rural residential subdivision. Most allocated connections are utilised (6 unused connections remaining) and it is not intended that this supply area be extended. The supply is able to meet current peak demands without the need for water restrictions. Any further development in this area could potentially be served by connection to the nearby Christchurch City Council water supply.

Table 4‑2 Capacity Summary

	Flow Rate (L/s)	Daily Volume (m³)	Annual Volume (m³)	Comments
Abstraction Capacity	11.7	1010	-	1 x bore pump (nom capacity)
Consented Take	12	1037 *	124,000
Peak Demand	15.7 **	925 ***	78,740 ****

* inferred value, ** 1 Feb 2015, *** 26 Jan 2015, **** 2014

4.5 Resource Consents

The Claremont water supply has a number of resource consents. Table 4‑3 shows the water take permitted by the resource consents for this scheme.

Table 4‑3 Resource Consents

Consent	Description	Location	Date Issued	Expiry Date	Consented Max Instantaneous Flow (L/s)	Consented Max Daily Volume (m³/day)
CRC000094	to take groundwater from a proposed bore, at or about map reference NZMS 260 M36:6658-3801 for the domestic supply of a residential subdivision.	Waterholes Road, TEMPLETON	17-Nov-99	15-Nov-34	12

This consent is currently under the developer's name (Debon Holdings Limited). Council is working to resolve this issue.

4.6 Water Quality

The Claremont water supply is a secure source and is currently sampled weekly within the treatment plant and monthly within the reticulation.

The following details E. coli transgressions for the sample periods 2012 to 2020.

Treatment

There have been no E. coli transgressions for this period in the treatment plant.

Reticulation

There have been no E. coli transgressions for this period in the reticulation zone.

Chemical Analysis

The following is a summary of the raw water chemical analysis carried out at the Claremont Water Supply.

Table 4‑4 Claremont Water Supply Raw Water Chemical Analysis Summary

Parameter	Standards	2015	2017	2020	Status
Total Lead (g/m3)	0.01 (Maximum Acceptable Value)	0.00017	<0.00011	<0.00011	✓
pH (pH units)	7-8.5 (Guideline Value)	7.8	7.8	7.9	✓
Total Hardness (g/m3 as CaCO₃)	<200 (Guideline Value)	39	38.4	38.6	✓
Total Calcium (g/m3)	n/v	13.4	13.28	13.31	✓
Total Iron (g/m3)	<0.2 (Guideline Value)	<0.021	< 0.021	<0.021	✓
Total Sodium (g/m3)	<200 (Guideline Value)	5.9	10.89	5.28	✓
Nitrate - Nitrogen (g/m3)	11.3 (Maximum Acceptable Value)	1.08	4.00	1.21	✓

4.7 Scheme Assets

A summary of material and diameter for pipes in Claremont is shown below by Figure 4‑3 and Figure 4‑4.

Figure 4‑3 Pipe Material – Claremont

Figure 4‑4 Pipe Diameter – Claremont

4.8 Operational Management

The water supply is operated and maintained under two maintenance contracts as follows:

Contract 1241: Water Services Contract. Contract is with SICON who undertakes investigations, conditions inspections, proactive and reactive maintenance and minor asset renewals; and
Contract 1202: Parks and Reserves Contract. Contract is with SICON who undertakes the maintenance of land scape features related to water services e.g. mowing, gardens etc.

Water quality sampling is completed under an agreement with Food and Health Ltd as required.

4.9 Photos of Main Assets

Photo 1: Bore	Photo 2: Reservoir
Photo 3: Pump shed

4.10 Risk Assessment

A risk assessment has been undertaken for the Claremont scheme. The key output from the risk assessment is the identification of any extreme and high risks which need to be mitigated. In order to mitigate these risks they have been included and budgeted for in the projects within this LTP. Table 4‑5 outlines the risk priority rating, Table 4‑6 outlines the risks and the list of key projects is found in Table 4‑11.
Table 4‑5 Risk Priority Rating

Risk Score	Level of Risk	Risk Response
> 50	Extreme	Awareness of the event to be reported to Council. Urgent action to eliminate / mitigate / manage the risk. Document risk and action in the AMP.
35-50	Very High	Risk to be eliminated / mitigated / managed through normal business planning processes with responsibility assigned.
14-35	High	Manage risk using routine procedures.
3.5-14	Moderate	Monitor the risk.
< 3.5	Low	Awareness of the event to be reported to Council. Immediate action required to eliminate / mitigate / manage the risk. Document risk and action in the AMP.

Table 4‑6 Risks – Claremont

Risk	Action/Project	Year Identified	2014 Risk Rating	2017 Risk Rating	Residual Risk Rating
If reservoir overflows, into control shed	Test reservoir overflow and ensure electrical controls in nearby building is not affected. Install splash protection e.g. a curtain.	2014	12	12	6
Electrical failure due to lightning or network spikes	Install surge diverters	2014	6	6	6
Failure to meet NES water meter standards	NES Water Meter Compliance	2014	20	6	6
Inability to collect income from non-metered properties	Install property water meters	2014	27	0.6	0.6
Non-compliance with the DWSNZ	DWSNZ - Age Testing	2014	6	0.7	0.7
Non-compliance with the DWSNZ	DWSNZ - Bore-head security	2014	6	6	6
Non-consented activities	Renewal of consents	2014	27	27	6
Overflow of tank into treatment building	Vent building outside	2017		6	0.2
SCADA control for remote control of pumps	Install remote controls	2017		4	0.2

The list of district wide risks can be found in 5Waters Activity Management Plan: Volume 1.

4.11 Asset Valuation Details

The total replacement value of assets within the Claremont water scheme is $687,006 as detailed in Table 4‑7 below.

Table 4‑7 Replacement Value, Claremont

Asset Class 1	Asset Class 2	Sum of Replacement Value
Plant and Equipment		$310,564
Water Reticulation	Hydrant	$31,284
	Lateral	$29,231
	Pipe	$257,836
	Supply Point	$45,666
	Valve	$12,425

4.12 Renewals

The renewal profile has been taken from the 2019 5 Waters Valuation. A graph showing the renewals for this scheme are shown by Figure 4‑5 below. There is a backlog of overdue renewals.

Figure 4‑5 Claremont Water Renewal Profile

4.13 Critical Assets

The criticality model for Claremont has been updated for the 2021 AcMP. The methodology of the criticality model can be found in 5Waters Activity Management Plan: Volume 1 and it provides details of how the criticality has been calculated for the reticulation assets. Table 4‑8 and Figure 4‑6 below shows the calculated criticality for all of the assets within this scheme that have a recorded known length.

Table 4‑8 Length of Assets per Criticality Level

Criticality Bands		Length (m)
5	Low	1,257
4	Medium-Low	1,134
3	Medium	812
2	Medium-High	0
1	High	0

Figure 4-6
CLAREMONT Water - Criticality
Open larger map: 'Water Criticality'

4.14 Asset Condition

The asset condition model was run for Claremont in 2021. The methodology of the model can be found in 5Waters Activity Management Plan: Volume 1 which provides details of how the model has been calculated for the pipe reticulation assets. Figure 4‑7 below shows the level of asset condition for these assets within this scheme that have a recorded known condition.

Figure 4-7
CLAREMONT Water - Condition
Open larger map: 'Water Condition'

Table 4‑10 provides a description of the condition rating used within the condition model.

Table 4‑9 Asset Condition Grading

Condition Rating	Grading
1.0	Excellent
2.0	Good
3.0	Moderate
4.0	Poor
5.0+	Fail

The number of pipe faults is also measured through the asset management system. Figure 4-8 shows the known historic pipe failures within this scheme.

Figure 4-8
Claremont Water - Pipe Faults map
Open larger map: 'Water Pipe Faults'

4.15 Funding Program

The 10 year budgets are shown by Table 4‑12. Budgets are split into expenditure, renewals, projects and capital projects. Expenditure and renewals have been reported on a district-wide basis in Volume 1.

All figures are ($) not adjusted for CPI “inflation". They are calculated on historical data, and population growth where relevant.

Table 4‑10 Budget Summary

Years	Projects	Capital Projects
2021/2022	-	-
2022/2023	-	-
2023/2024	-	-
2024/2025	-	-
2025/2026	-	$200,000
2026/2027	-	-
2027/2028	-	$200,000
2028/2029	-	-
2029/2030	-	-
2031/2032	-	-
Total	-	$400,000

An explanation of the categories within the budgets are as follows below:

Expenditure consists of operation and maintenance costs;
Renewals are replacement of assets which are nearing or exceeded their useful life;
Projects are investigations, decisions and planning activities which exclude capital works; and
Capital projects are activities involving physical works.

Table 4‑11 Key Projects

Account Label	GL	Description	Year 1($)	Year 2($)	Year 3($)	Years 4 to 10	Funding Split *
Capital Projects	-	Reservoir internal wall	-	-	-	$200,000	TBC
Capital Projects	-	Additional source: 140m deep bore	-	-	-	$200,000	TBC

* Where LoS refers to Level of Service and G refers to Growth

The list of district wide projects can be found in 5Waters Activity Management Plan: Volume 1.

Discussion on Projects

Projects have been determined based on their:

Relevance to the scheme
Requirement to be completed under legislation
Ability to bring the scheme up to or maintain the Level of Service required under council's Asset Management Policy.

Many projects are jointly funded by more than one scheme and activity. Each scheme pays a pro-rata share only, equivalent to the number of connections.

Discussion on Capital and Projects

Where relevant, Capital (Levels of Service) and Capital (Growth) projects have been included in the scheme financial details.

Levels of Service Projects and growth splits have been provided to ensure the costs of population driven works are clear.