​​2   Ellesmere Land (No. 3) Drainage District

2.1       Scheme Summary

2.2       Key Issues

There are no key issues are associated with the Ellesmere Drainage District.  A list of district wide issues are located in 5Waters Activity Management Plan: Volume 1.

2.3       Overview & History

The Ellesmere scheme has a rating area of 1,266ha, servicing a total area of 2,820ha between Curries Road and Bethels roads with drainage outlets for this scheme via the Selwyn River in the vicinity of Coes Ford.  The ultimate receiving environment for this area is Te Waihora (Lake Ellesmere).

Miles drain located on the eastern extreme of the Ellesmere scheme was an addition to the original scheme. The drainage system includes a number of privately owned flood flap valves.

The land drainage scheme was constructed to remove groundwater, allowing farming to occur.  As a secondary use, stormwater from properties is also discharged to the network of open drains.

In 2011, a variation to the Te Waihora Water Conservation Order was made, bringing a strong cultural focus into place.  The Selwyn - Waihora Zone Committee (established under the Canterbury Water Management Strategy) also released its Zone Implementation Plan (ZIP) and ZIP addendum.

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​​ Figure 2-1
ELLESMERE Land drainage - Scheme map
Open larger map: 'Land drainage Scheme'

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2.4       Resource Consents

There are no existing consents for this land drainage scheme. 

Land drainage activities are controlled through Rules 5.57 and 5.58 under the Land and Water Plan. An application was lodged in November 2011, with a request that it be put on hold pending discussion with stakeholders.

2.5       Scheme Assets

This scheme is predominately Land drainage channels which are excavated open channels that intercept, convey and discharge groundwater to allow productive use of land. 

2.6       Operational Management

Council delegates some aspects of management of the Land Drainage network to 9 Land Drainage Committee's comprising of local residents with an interest in the Land Drainage network.  Council Service Delivery Staff work alongside the Committee's to prioritise and facilitate maintenance activities which are undertaken by a number of local contractors. 

2.7       Photos of Main Assets

​ Photo 1: Miles Drain – flood bank left hand bank

​ Photo 2: Discharge from Silverstream Drain

2.8       Risk Assessment

A risk assessment has been undertaken for the Ellesmere 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 2‑1 details the risk priority rating, Table 2‑2 outlines the risk identified in this scheme and Table 2‑7 details the key projects.

Table 2‑1 Risk Priority Rating

Table 2‑2 Risks – Ellesmere

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

2.9       Asset Valuation Details

The total replacement value of assets within the Ellesmere Scheme is $3,338,222 with further details in Table 2‑3 below. All of the value is made up of channels.

Table 2‑3 Replacement Value, Ellesmere

Channels are broken down into drains, pipes and stock banks. The Ellesmere Land drainage district is made up of classified drains.

2.10       Renewals

The renewal profile has been taken from the 2019 5Waters Valuation. There are no renewals for this scheme. This asset has a maintained infinite life.

2.11       Critical Assets

The criticality model for Ellesmere 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 2‑4 and Figure 2‑2 below show​ the calculated criticality for all of the assets within this scheme that have a recorded known length.

Table 2‑4 Length of Assets per Criticality Level

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​​ Figure 2-2
ELLESMERE Land drainage - Criticality map
Open larger map: 'Land drainage Criticality'

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2.12       Asset Condition

The asset condition model was run for Ellesmere in 2021. The methodology of the model can be found in 5Waters Activity Management Plan: Volume 1 and it provides details of how the model has been calculated for the reticulation assets (particularly pipes). There is no known recorded condition for assets within this scheme.

2.13       Funding Program

There are no projects specific to the Ellesmere scheme in the 10 year LTP budgets, however the scheme will benefit from a number of district-wide initiatives. ​​The list of district wide projects can be found in 5Waters Activity Management Plan: Volume 1.

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