Managing Dunedin’s water and transport infrastructure

Today, Dunedin’s water and transport infrastructure are worth $4.1 billion (gross asset replacement cost).

3 Waters
Several factors are considered when managing Dunedin’s water infrastructure:
- asset age, condition and performance^[1]
- changing weather patterns (such as rainfall intensity and drought frequency)
- changes to population or land use
- changes to legislative and regulatory requirements, such as drinking water standards and national policy statements.
When infrastructure assets are not performing as required, or are unable to meet new standards, capital projects are scoped so deficiencies can be addressed. These projects are prioritised based on the criticality of the assets and the likely impact of any loss of service and programmed into 3 waters budgets. Strategic Planning is currently underway for water and wastewater, and will soon commence for stormwater, in the form of system planning. For wastewater it considers from the source (e.g. residential, commercial and industrial customers) to disposal (e.g. the ocean) and for drinking water it considers from the catchment (e.g. a river) to the customer’s tap. Long-term optimal solutions can be developed by looking holistically at factors such as capacity, performance, growth, new standards, overflows, and storage.
Funding for infrastructure is categorised in two ways. Renewals funding is targeted at maintaining existing service levels, whereas new capital funding can both maintain existing service levels (where current assets can no longer achieve required outputs e.g. raw water quality changes require increased treatment to maintain standards) or be targeted at increasing levels of service in order to meet modern standards. These standards include new consent conditions for water take and discharge permits, changes to the drinking water standards, health and safety improvements, increasing capacity to meet additional demand and improvements to operational efficiency.
Both renewals funding and new capital funding are often used together on specific projects. The renewal of an undersized pipe will use renewal funding in the ‘like for like’ replacement portion of the works, while an incremental change in pipe diameter is considered ‘new capital’.
Footnote
1. 3 waters level of service measures are set out in the 10-year plan.
Transport
Several factors are considered when managing Dunedin’s transport infrastructure:
- asset age, condition and performance
- changes to population and land use
- changes to GPS on land transport
- maintenance to repair defects and preserve remaining life.
Most of the transport network’s maintenance, renewal and new capital programmes are subsidised by Waka Kotahi at a funding assistance rate of 53% - 51%. Every year a funding bid is submitted to Waka Kotahi for co-funding the transport network programmes. In recent years construction prices have increased significantly, creating financial pressures in delivering renewal and maintenance programmes with limited Waka Kotahi funding and corresponding DCC share.
This Infrastructure Strategy assumes that there will be constraints in Waka Kotahi funding (partly driven by the impact of the COVID-19 pandemic and current income shortfalls in petrol tax) along with changing priorities for Waka Kotahi funding. In the short term at least, renewals co-funding from Waka Kotahi will be limited to $7 - $8 million per annum, short of the $10 - $14 million per annum based on standard Waka Kotahi subsidy rates of 51% – 53%. Investing in the renewal of the network will continue, to ensure levels of service are maintained. It is anticipated that in the short term at least there will be an additional funding requirement from the DCC. This will be financed through a combination of debt and rates funding over the course of the 10 year plan.
The Dunedin Integrated Transport Strategy 2013 is an overarching strategy covering the whole of Dunedin’s transport system and is designed to enable the DCC to review its investment priorities and ensure they are relevant to the current and future needs of Dunedin. It identifies and outlines areas of focus developed from several transport challenges and issues that Dunedin faces. The Strategy focuses on transport choice whilst maintaining the levels of service for road users. A corresponding asset management plan determines a condition-based asset maintenance and renewal programme that sets the level of investment required to maintain the existing transport infrastructure across Dunedin City.

Assessing the condition of Dunedin’s network infrastructure

How does the DCC assess the condition of water supply assets?
Methods for assessing the condition of the DCC’s 3 waters infrastructure vary by asset type but typically involve visual or physical inspection. Water pipes are more difficult to assess due to the continual flow of water through them. Instead, small sections of pipe must be taken out for inspection. The condition of treatment plants is routinely inspected by DCC staff to ensure assets are appropriately maintained. Specialist engineering advice is used as required. The DCC 3 Waters Group is currently undertaking a series of improvements to water treatment asset condition assessments.

Summary of water supply assets

Asset condition		Asset capacity
P1	Significant number of assets in poor condition	P1	Significant capacity issues currently experienced
P2	Some assets in poor condition	P2	Capacity issues in some areas and/or capacity issues can be expected
P3	No or few assets in poor condition	P3	No or minor capacity issues and none are currently expected

Asset group and type		Purpose and description	Number/ Length	Value $000	Asset condition		Asset capacity
Metropolitan Water Systems including the Dunedin City (Mount Grand, Southern and Port Chalmers) and Mosgiel supplies
Raw Water Supply	Bore pumps and intake structures	Extract raw water from surface sources - from Deep Creek, Deep Stream (supplying Mount Grand Treatment Plant), Silverstream and tributaries (supplying Southern Treatment Plant), Cedar Farm Creek and Brosnahan’s Creek (supplying the Port Chalmers Treatment Plant).	18	3,326	P2	Intakes and pumps in active service are maintained in good condition.	P3	Current risks in supply demand within the network are planned for remedial action within the short – medium term, while longer-term risks will be addressed as part of water system planning to inform the 2024-34 10 year plan. The recent refurbishment of the Ross Creek Reservoir is one of several projects aimed at increasing the security of raw water supply to the Dunedin metropolitan area. Existing capacity, while good, is susceptible to drought and the failure of critical assets. The ability to supply water in such events will be improved when the Ross Creek Reservoir is able to supply Mount Grand Water Treatment Plant via the building of a new supply pipeline.
	Raw water pipelines and pump stations	Take untreated water from source to treatment plants. This includes the Taieri River pipe bridge carrying water from Deep Creek and Deep Stream, and the Puddle Alley and Silverstream pump stations, pushing water from the Taieri bores and Silverstream respectively, up to the Southern Reservoir.	157km pipelines one pipe bridge two pump stations	232,528	P2	The majority of the raw water pipelines are in good condition, however sections of the Deep Stream and Deep Creek pipelines upstream of the Taieri River pipe bridge are in poor condition, with specific concerns relating to the joints between sections of pipe. Enabling supply from the Ross Creek Reservoir will make these pipelines less critical, enabling the renewal of the pipelines to be pushed out while various long-term options are considered. Repairs to the pipelines are made as required.
	Raw Water Reservoirs	Raw water storage for supply to treatment plants (dams), including Port Chalmers (Cedar Farm and Rossville), Mount Grand and Southern reservoirs as ‘live’ supplies, with Ross Creek and Sullivan’s Dam not currently live supplies.	Six	21,454	P1	Raw water reservoirs are managed in accordance with the Dam Safety Assurance Programme (DSAP) overseen by the consenting authority. All raw water reservoirs are in good condition, however ongoing work will be planned as required by the DSAP.
Water Treatment	Treatment Plants	Plant and equipment used to screen, filter, pH adjust, and disinfect water to meet the Drinking Water Standards New Zealand (DWSNZ), and plant and equipment used to monitor and control individual processes.	Three plants (Mt Grand, Southern and Port Chalmers)	77,319	P2	Plant and equipment at the water treatment plants are maintained in good condition to ensure water produced meets drinking water standards. Recent condition assessments have produced a plan of renewals over the period of the plan to ensure the treatment plants can continue to supply drinking water which meets national standards.		Recent process capacity assessments showed most of the water treatment plants can cope with current and future demand. Where future demand risks have been identified, system planning will produce the best practicable option, which may include plant rationalisation. The Port Chalmers Treatment Plant runs seasonally (October to April), when peak demand from cruise ships is unable to be met by the Dunedin city supply alone. This is an expensive water supply arrangement. Rationalisation of this supply is planned on completion of feasibility studies, which is expected to result in water supply from Mount Grand Water Treatment Plant and a new supply pipeline.
Treated Water Distribution	Treated Water Pipelines and Pump Stations	Transport water from treatment plants around the network, with pump stations boosting water to areas of the network unable to be reached by gravity feed alone. Includes the 25km treated water pipeline connecting the northern water schemes of Waitati, Warrington and Seacliff to the Dunedin City water supply.	989 km pipelines 18 pump stations 23,626 minor point assets (valves, hydrants and meters)	456,364	P1	As with some other 3 waters networks, areas of the network are in excellent condition while other areas are in poor or very poor condition, which affects flow and pressure to customers. Ongoing renewals are targeted at areas of very poor condition. Renewals of flow meters have been stepped up since 2010 but many are still outside their expected lives and are likely to be in poor condition for assets of this type.	P3	Capacity in the treated water network is defined as being where the flow rate of water supplied by an individual fire hydrant within the network meets the requirements of the NZ Fire Service Code of Practice for Fire Fighting Water Supplies (Standards NZ reference NZ PAS 4509:2008). For the Dunedin City and Mosgiel water supplies, some of hydrants across the city are non-compliant with the standard. This generally relates to water mains installed before 1960, where the 100mm diameter pipes were appropriately sized at the time of installation but are undersized for today’s demand. In peak summer demand, some pipelines do not meet sufficient capacity and so these are targeted for replacement. A programme of renewals and new capital works targeting these areas is underway, with targeted pipeline renewals as the next package of works, aimed at improving pressure management and fire flows.
	Treated Water Reservoirs	Treated water storage within the network to meet peak demand and ensure supply in the event of network outages.	44	33,159	P3	Regular maintenance means that most city reservoirs are in good condition. Some reservoirs will require replacement within 50 years and have been accounted for as part of the forecast renewals.	P3
	Service connections	Service lines, tobies, manifolds and backflows preventers connecting private properties to the water network in a safe manner.	44,132	111,597	P2	A significant proportion of service connections in the metropolitan area are older style ‘toby’ connections. These will be replaced with modern manifold connections when capital works are being undertaken in an area.	P2
Rural Water Supplies
Waikouaiti/ Karitane/Merton		Extract water from Waikouaiti River, treat to drinking water standards and pump or gravity feed to properties in the Waikouaiti urban water supply area, and the Karitane and Merton rural water supply areas.	one plant 96 km pipelines three pump stations 2,638 minor point assets (valves, hydrants and meters)	28,485	P2	The Waikouaiti water treatment plant is in generally good condition though some assets with shorter lifespans (filter membranes) are nearing the end of their useful lives and in correspondingly average to poor condition. There is a scheme which will extend into the early years of the plan which renews these assets. Condition of water mains in Karitane is of concern with a high number of breaks per kilometre being an indicator of poor asset condition. This will be addressed through the current renewal work in this area.	P1	There are identified capacity issues in the Waikouaiti and Karitane treated water networks. Recent capital works have been completed in Waikouaiti to address some of these issues; further works are programmed within the Karitane township and from the Waikouaiti Reservoir to the Waikouaiti township in the near future to improve capacity. There are still known capacity issues in the Edinburgh Street (Waikouaiti) area, which will not be completely alleviated by the recent and planned upgrade works. Further work will be programmed in year 7-10 of the strategy to improve capacity in this area. The Merton supply is a restricted rural scheme with enough capacity for the foreseeable future. Upgrades to the Waikouaiti Water Treatment Plant will improve taste and aesthetics.
Outram		Extract water using a bore pump located adjacent to the Taieri River, treat to meet drinking water standards, and gravity fed to properties within the Outram water supply zone.	One plant 17 km pipelines one pump station 961 minor point assets (valves, hydrants and meters)	6,359	P3	Condition within the Outram network is generally good to excellent. Recent condition assessments of the treatment plant have produced a plan of renewals over the period of the plan to ensure the plant can continue to supply drinking water which meets national standards.	P2	Recent capacity assessments have shown that work is needed to meet future demand within the treatment plant. The strategic investment plan for longer term upgrades are part of the water system planning.
West Taieri Rural Scheme (Restricted)		Water extracted from the Waipori River, treated to meet drinking water standards, and pumped to Dunedin Airport and privately-owned tanks within the West Taieri water supply zone.	One plant 127 km pipelines five pump stations 392 minor point assets (valves, hydrants and meters)	8,921	P2	The West Taieri water treatment plant is in generally good condition, although some shorter lifespan assets are nearing the end of their useful lives and are in correspondingly average to poor condition. The piped network is also generally in good condition with a relatively small number of breaks per kilometre.	P1	There is sufficient capacity within the West Taieri Rural Scheme to meet demand for the foreseeable future.

How does the DCC assess the condition of wastewater assets?

Visual inspection methods, such as closed-circuit television (CCTV) filming, are used to assess the condition of wastewater pipes. The results from these CCTV inspections are used to determine if assets need to be repaired or replaced.

DCC staff undertake visual and physical inspections of the condition of treatment plants and pump stations to ensure assets are appropriately maintained. Specialist engineering advice is used as required. Data on material /unit type, age, condition, performance, location, capacity, criticality and remaining life is collected for 3 waters assets. Confidence in the condition information about the DCC’s wastewater network and treatment assets ranges varies. The DCC 3 Waters Group is currently undertaking a series of improvements to wastewater treatment asset condition assessments.

Summary of wastewater assets

Asset condition		Asset capacity
P1	Significant number of assets in poor condition	P1	Significant capacity issues currently experienced
P2	Some assets in poor condition	P2	Capacity issues in some areas and/or capacity issues can be expected
P3	No or few assets in poor condition	P3	No or minor capacity issues and none are currently expected

Asset group and type		Purpose and description	Number/ Length	Value $000	Asset condition		Asset capacity
Metropolitan Wastewater Systems	Tahuna catchment
	Wastewater Network	Transport untreated wastewater from customers’ point of discharge to Tahuna wastewater treatment plant.	618 km pipelines (including 4.5 km main interceptor sewer) 39 pump stations 14,176 network access points (manholes, lampholes etc.)	520,352	P1	With a high proportion of early 20^th century pipework, much of the network feeding the Tahuna WASTEWATER TREATMENT PLANT is in poor condition. A large portion of the network is older earthenware pipe with more joints than modern equivalents. As they deteriorate, these joints allow considerable volumes of water to infiltrate into the network, exceeding network capacity during heavy rainfall events and resulting in wastewater overflows downstream. Pipeline renewals are focussed on areas of high inflow and infiltration.	P1	High intensity rainfall events can lead to inflow and infiltration entering the network with wastewater systems becoming overwhelmed and overflowing, while at the treatment plants wash out can occur which severely disrupts treatment processes. Incapacities upstream in the Tahuna wastewater catchment overflow into stormwater catchments flowing into the South Dunedin area, further exacerbating flooding issues in the area. The performance and possible solutions to wet weather flow management will continue, by undertaking flow monitoring and incorporating the ground water model information. The best practicable solutions will be assessed for cost and their ability to deal with growth, resilience and carbon impacts.
	Wastewater Treatment and discharge to ocean outfall	Treat wastewater to meet discharge consent conditions.	One treatment plant 1.1 km outfall pipe off Middle Beach	136,251	P2	The upgrade of the Tahuna wastewater treatment plant means parts of the plant are in good to excellent condition. Some sections or the original building will require some further remedial works in the short to medium term. The condition of the rising mains from the Musselburgh pump station to Tahuna wastewater treatment plant are poor, with investigations into options starting in 2020 to inform remedial action in the short-medium term.	P3	The recent process capacity assessments have shown the Metropolitan treatment plants have capacity to treat to current environmental standards now and in the future, but small-scale renewals are needed to continue capacity as the assets age. As with most city plants, wet weather flows can overwhelm the system and solutions will be developed as part of the wastewater system planning.
	Green Island catchment (excluding Mosgiel)
	Wastewater Network	Transport untreated wastewater from customers’ point of discharge to Green Island wastewater treatment plants	121 km pipelines 26 pump stations 2,037 network access points (e.g. manholes lampholes.)	117,419	P3	The Green Island network is generally in good condition given its age, however the plant does receive high wet weather flow volumes due to inflow and infiltration problems in the catchment.	P2	Some treatment capacity is available within the Green Island network, however wet weather flows can overwhelm the system. Solutions will be developed as part of system planning.
	Wastewater Treatment and discharge to ocean outfall.	Treat wastewater to meet discharge consent conditions.	one treatment plant 850m outfall off coast at Waldronville	26,962	P2	The Green Island wastewater treatment plant is in average condition given its age. Smaller scale renewals and process changes are needed to continue to meet levels of service and implement short-term wet weather flow management operational processes.	P2	The recent process capacity assessments have shown the Metropolitan treatment plants have capacity to treat to current environmental standards now and in the future, but small-scale renewals are needed to continue capacity as the assets age. As with most city plants, wet weather flows can overwhelm the system and solutions will be developed as part of the wastewater system planning project.
	Mosgiel catchment (includes Allanton)
	Wastewater Network	Transport untreated wastewater from customers’ point of discharge to wastewater treatment plants	113km pipelines six pump stations 2,226 network access points (manholes, lampholes etc.)	87,354	P2	Some areas of the Mosgiel wastewater network are in excellent condition, while other areas are in poor or very poor condition. While the overall network is a similar age to the Green Island network, the way in which the Mosgiel network was constructed means that it experiences significantly higher infiltration during rainfall events. During heavy rainfall events groundwater levels become elevated which increases the amount of groundwater infiltrating into the wastewater network.	P1	There are significant incapacities in the network servicing the Mosgiel wastewater treatment plant catchment. High levels of inflow and infiltration result in wastewater overflows to roads, homes and properties during heavy rainfall events. Preliminary investigative work has shown that large-scale pipeline and pump station upgrades are needed to reduce the risk of flooding.
	Wastewater Treatment and transfer to Green Island	Treat wastewater to remove solids and organic matter, transfer to Green Island Wastewater for UV treatment prior to discharge.	one treatment plant 20 km transfer line to Green Island	25,812	P2	The Mosgiel wastewater treatment plant has some mechanical, electrical and civil plant items in poor condition resulting in increased operations and maintenance costs. Renewals will be stepped up to improve overall plant condition to maintain service while awaiting long term options from system planning.	P1	While there is sufficient capacity within the Mosgiel wastewater treatment plant for dry weather flows, the pipeline that transfers effluent from the Mosgiel wastewater treatment plant for final treatment at the Green Island wastewater treatment plant is at capacity during heavy rainfall events, resulting in a bottleneck at the treatment plant. Investigative work is underway to determine the most appropriate solution long term.
Rural Wastewater Schemes	Waikouaiti (including Karitane), Seacliff, Warrington and Middlemarch catchments
	Wastewater Network	Transport untreated wastewater from customers’ point of discharge to wastewater treatment plants	43 km pipelines 10 pump stations	29,002	P2	Rural wastewater network assets vary between ‘very good’ and ‘poor’ condition. The Karitane portion of the network is in very good condition having been installed as an entirely new network in 1983. Renewal of older assets is incorporated as part of forecast renewals as assets reach the end of their useful lives.	P2	There is incapacity in the Waikouaiti/Karitane network which show up as minor wastewater overflows at the Karitane No. 1 pump station during heavy rainfall events. There are no known network capacity issues in Seacliff or Warrington. There are known capacity issues in Middlemarch due to inflow and infiltration issues evidenced by minor network overflows in wet weather, work is underway to understand the best ‘whole of system’ solution for the area.
	Wastewater Treatment and discharge to land	Treat wastewater to meet discharge consent conditions.	four treatment plants and associated disposal areas	4,297	P2	The rural wastewater treatment plants are generally in good condition, with renewals planned over the next 10 years as discharge consents expire. Treatment options will be considered as renewals are planned, with Seacliff being the first of the northern wastewater treatment plants programmed for renewal.	P3	There is enough capacity within the existing wastewater treatment plants for current and forecast flows in the short term. The plants will be upgraded over the next 10 years prior to their discharge consents expiring, with any forecast capacity changes accounted for as the upgrades are planned.

How does the DCC assess the condition of stormwater assets?

The condition of stormwater pipes is primarily assessed through CCTV filming. The results from CCTV inspections are used to determine whether assets need repair or replacement, and when this needs to happen. The condition of pump station assets is routinely inspected by DCC staff to ensure assets are appropriately maintained. Specialist engineering advice is used as required. Data on material /unit type, age, condition, performance, location, capacity, criticality and remaining life is collected for 3 waters assets. The DCC 3 Waters Group is currently planning to undertake a series of improvements to stormwater asset condition assessments.

Summary of stormwater assets

Asset condition		Asset capacity
P1	Significant number of assets in poor condition	P1	Significant capacity issues currently experienced
P2	Some assets in poor condition	P2	Capacity issues in some areas and/or capacity issues can be expected
P3	No or few assets in poor condition	P3	No or minor capacity issues and none are currently expected

Area	Asset type	Purpose/ description	Number/ Length	Value $000	Asset condition		Asset capacity
South Dunedin (includes the individual stormwater catchments of Orari Street, St Clair, Portsmouth Drive, and South Dunedin)	Pipe network	Transport stormwater water to pump stations or outlets	97km pipelines 2,454 network access points (manholes, lampholes etc.)	155,861	P2	Condition of the pipe network in the wider South Dunedin stormwater catchment area varies widely based on the age, diameter and construction materials of individual pipes. Older large diameter pipes are generally in sound condition, due to the construction methods of the era.	P1	In heavy rainfall events the stormwater network in South Dunedin can become overwhelmed, resulting in flooding of roads, homes and properties. This is exacerbated by areas of high ground water, particularly around high tide. Hydraulic modelling indicates the stormwater network is performing below the expected level of service. The DCC is working with the ORC and GNS Science to develop and incorporate groundwater into the hydraulic model for the area. Significant capital works are proposed to bring these assets up to currently accepted design standards.
	Pump stations	Pump stormwater during times of significant inflow	three pump stations	5,120	P2	The majority of pump stations are in average condition with some requiring attention to wet wells, pipes and pumps.	P3	Pump station capacity is generally good; issues relate to incapacity within the wider network.
Mosgiel, East Taieri and Outram	Pipes	Transport stormwater water to pump stations or outlets	57km pipelines 1,023 network access points (manholes, lampholes etc.)	66,442	P2	Condition of the pipe network in the Mosgiel, East Taieri and Outram area varies widely based on the diameter and construction materials of individual pipes.	P1	Mosgiel is a very sensitive stormwater catchment; the area is the flood plain for the Taieri River and Silverstream and is underlain by the extensive Taieri Aquifer which is responsive to river levels. The DCC stormwater network discharges into the Taieri River, Silverstream and other tributaries, and when those waterways are high stormwater discharge is impeded. Mosgiel frequently experiences catchment-wide nuisance flooding in small rainfall events. Deep flooding and property flooding are experienced in some areas. Capital works are proposed after modelling improvements have assessed the best practicable option to bring areas of the network with capacity issues up to currently accepted design standards.
Mosgiel, East Taieri and Outram	Pump stations	Pump stormwater during times of significant inflow	five pump stations	1,284	P2	Many pump stations are in average condition with some requiring attention to wet wells, pipes and pumps.	P2	Pump station capacity is generally fair; issues have tended to be with incapacity within the wider network. Capital works are planned to enhance pump station performance in conjunction with pipe improvements above.
Centre City (includes the individual catchments of Halsey Street, Mason Street, Kitchener Street and Ravensbourne Road) Outlying areas: Port Chalmers, Brighton/Waldronville, Green Island, Waikouaiti/ Karitane and Warrington.	Pipes	Transport stormwater water to pump stations or outlets	233km 7,406 network access points (manholes, lampholes etc.)	265,152	P3	Condition of the pipe network in the Centre City area varies widely based on the age, diameter and construction materials of individual pipes. Older large diameter pipes are mostly in sound condition, due to the construction methods of the era. Capital works are proposed via the Central City, Tertiary Precinct and general renewals projects.	P2	Capacity issues exist in small discrete areas of the network. These issues will be addressed through focused capital works. The DCC is working with the ORC and GNS Science to develop and incorporate a groundwater model for the central city area. Northern area – there are limited networks installed in the townships of Waikouaiti, Karitane and Warrington. Both – stormwater system planning will be developed in the early years of this 10-year plan and will provide a basis for future investment
	Pump stations	Pump stormwater during times of significant inflow	three pump stations	1,541	P2	Many pump stations are in good condition with some attention required on specific wet wells, pipes and pumps. The pump station renewals projects target these issues.	P3	Pump station capacity is generally good.

How does the DCC assess the condition of transport assets?

Assessing the condition of above ground infrastructure like roads, cycleways and footpaths is more straightforward than assessing the condition of pipes and other underground infrastructure. The transport team uses a rolling programme of condition assessments to inform its maintenance and renewals decisions which translates into the Asset Management plan which enables co-funding with Waka Kotahi. The level of confidence in the knowledge of the DCC’s transport assets is high.

Summary of transport assets

Asset condition		Asset capacity
P1	Significant number of assets in poor condition	P1	Significant capacity issues currently experienced
P2	Some assets in poor condition	P2	Capacity issues in some areas and/or capacity issues can be expected
P3	No or few assets in poor condition	P3	No or minor capacity issues and none are currently expected

Asset group and type	Number/ Length	Value $000	Asset condition		Asset capacity
Paved roads	1,071 km	824,880	P2	Road pavements are in decline. Most of Dunedin’s sealed pavements have a theoretical useful life ranging from 60 – 100 years. 57% of pavements are aged 60 years and over. Based on condition assessment road condition is in decline. Smooth travel exposure for urban roads has sat below target for the past 11 years and has slowly declined.	P2	In capacity terms the Dunedin urban network is experiencing congestion at certain parts of the day. With the hospital re-build coming congestion will increase so intervention such as the Harbour Arterial bypass are required. In addition, offering Transport choices will be necessary to avoid congestion in the future.
Unsealed gravel roads	693km	28,284	P3	Gravel roads are maintained in a good condition; however, dust suppression methods have changed meaning potentially gravel roads will see higher volumes of dust.	P3	In capacity terms the Dunedin transport network is fit for purpose and can cope with traffic demands.
Footpaths & Cycleways	976 km	177,700	P1	There are a high percentage of footpaths that have exceeded their life, or are nearing the end of their economic life. Asphalt footpaths, that represent 76% of footpaths, have approximately 23% of the network at the end or nearing the end of their expected economic life. Concrete footpaths, that make up 6% of footpaths, have approximately 48% exceeding their expected economic life. Slurry seals, that represent 9% of footpaths, has 84% exceeding or nearing the end of their expected economic life. In the past 3 years 18% of the network have shown signs of deteriorating with a higher proportion moving to average condition from good to very good.	P3	In capacity terms Dunedin's footpaths are fit for purpose and can cope with pedestrian demands.
Road drainage Kerbing		175,571	P2	Kerb and channel condition are showing signs of decline. In 2019/20 6% of the network was in poor to very poor condition and without sustained investment this is expected to rise as more reach the end of their economic lives.	P3	Good
Signs, road markings and signals	20,403 signs 79 signalled intersections	10,721	P3	Signs, road markings and signals are maintained to a good condition.	P3	Good
Street lights	13,656 streetlights, 5 base stations, 3,313 tele-cells	27,900	P3	LED rollout will be complete by the middle of 2021	P3	Good
Bridges and large culverts	243 bridges 61 large culverts	100,217	P3	Bridges are in largely good condition.	P3	Good
Culverts and mud-tanks	5,734 culverts 8,331 mud-tanks	72,127	P2	Culverts have 5% in poor condition, 35% in average condition, 36% in good condition and 20% in very good condition. 4% are awaiting condition rating. The expected age for mud-tanks is 80 years. 74% are aged between 70-79 years thus nearing the end of their estimated lives, however in terms of their structural condition (which is largely unknown) as long as mud-tanks are adequately maintained it would be expected they would live well beyond their estimated lives.	P2	Given changing weather patterns, emphasis has been placed on ensuring culverts and mud-tanks are maintained to a high standard. Capacity may become an issue in the face of significant adverse conditions.
Seawalls	41 km	35,480	P2	Seawalls have 6% in very poor condition, 13% in poor condition, 23% in average condition, 39% in good condition and 19% in very good condition.	P2	Isolated areas of the network are compromised during significant weather events and will require future investment.
Retaining walls	31 km	27,832	P2	Many of Dunedin’s retaining walls were made many years ago and do not meet the current design requirements. Many provide resistance to surface erosion, rain and weathering but are not able to retain saturated retained material. As such many may be at risk of failure during high rainfall events and are routinely inspected and monitored for movement and condition.	P2	Given changing weather patterns and the age of some retaining walls capacity may become an issue.
Minor structures		9,950	P3	Minor structures are maintained regularly and are in good condition.	P2	Good

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