Conserving Aggregate

Road building delayed because governments ‘fail to plan for quarries’

This was the title of a Stuff article last month by Wayne Scott, the chief executive officer of the Aggregate & Quarry Association (AQA). He said:

politicians of all persuasions have paid only lip service to ensuring the rock, stone and sand which form the foundation for all infrastructure can actually be provided…

Transmission Gully’s delays and cost blowouts are the latest example. There’s never been a planning exercise for where the huge quantities of necessary rock, aggregate and sand would come from…

Quarry materials are cheap as chips – perhaps $20-$25 per tonne at the gate; the big cost comes in transporting it…

let’s just get some glasshouse transparency on where politicians see the materials coming from for all those infrastructure promises.

Image credit: AQA

The article links to the association’s report, A Briefing On The Quarry Sector And Aggregate Supply:

There will be increased demand for aggregate and sand to build ‘shovel ready’ and longer term projects. Additionally, the impacts of climate change including rising sea levels are going to put added pressure on rock supply for sea walls, riverbank protection and restoration. It is therefore more vital than ever that local aggregate resources throughout the country are identified, protected and effectively managed.

They are right that we need to plan well for the supply and transport of our aggregate for construction and they make a number of good recommendations, such as:

A cost/benefit analysis for recycling and re-use of construction waste be conducted by Government in consultation with industry, in order to establish the types of incentives, and/or penalties needed to achieve positive outcomes from the principle of a circular economy.

Aggregate recycling (such as at Mt Eden Station) needs to become standard practice.

Yet our level of aggregate use points to deeper problems

According to the AQA’s website:

In 2018, New Zealand recorded 41m tonnes of quarried material – about 8.6 tonnes per person. Unfortunately, there was a drop in quarry reporting in 2018 so the estimated production was 65M tonnes, or about 13.4 tonnes per person. That’s high by world measure.

The figures are somewhat imprecise but industry figures are using around 10 tonnes per capita – or the equivalent of a truck load for every New Zealander every year.

This is a profligate use of aggregate.

Accessing, extracting, processing and transporting one truckload of aggregate per person per year imposes large environmental, economic and social costs.

Government decision-making is of concern – not because it’s failed to streamline an easy supply of cheaply-transportable aggregate – but because it has created a wasteful level of demand for aggregate.

AQA are right to highlight the high costs of transporting aggregate and the need to minimise distances between quarries and projects. Of course, the same reasoning means we should leave reserves of aggregate in suitable locations for future generations. Since we value having aggregate reserves handy to cities and major infrastructure, we can understand how important proximity of supply will be in the future when climate change could be creating frequent economic and environmental shocks.

Retaining well-placed reserves while minimising truck km is one reason our aggregate use needs to drop. So how do we do that?

AQA say:

To build an average house, you need about 250 tonnes of aggregate – for use in concrete, asphalt, mortar and building products.

To build 1km of a two-lane motorway, you need around 14,000 tonnes of construction aggregates (400 truckloads)…

Over half of the aggregate produced in New Zealand is used on roads; a further fifth is used to construct commercial and residential building.

Halting the various roading expansion programmes would see a big reduction in aggregate demand. And since all roads need some aggregate for maintenance on an ongoing basis, it’s doubly critical we minimise the number of roads we leave as our legacy for our children. Litman’s graph of lane miles per capita for US urban regions shows how density is a factor in the different legacies of roading each city is leaving for the next generation, with obvious maintenance cost consequences.

The housing development model we use heavily determines our aggregate use, too. Plans that put housing into sprawl, such as the Auckland Development Strategy, consume vast amounts of aggregate. It goes into:

• driveways, parking spaces and garages at each residence,
• large carparks at retail stores and other locations, and parking lanes on streets, to cope with the cars that sprawl living demands, and of course
• new highways, bridges, widened arterials and developer-built local roads.

Mixed-use multi-storey buildings in compact neighbourhoods need aggregate too, regardless of how leafy and tree-lined we design them. So does maintaining and updating our existing infrastructure. But a development model that modifies our cities to become “quality, compact urban” is considerably less aggregate-hungry than sprawl development.

To conserve aggregate, we need to modify the Auckland Development Strategy, severely curtail our construction of new roading and sprawl, and house our population in Good Density. This is also the best way to reduce our emissions, become more climate resilient and improve our city.

Minimising the conflicts and negative environmental outcomes of quarrying

AQA recommend:

Government give local authorities greater direction in planning for key resource areas, in order to protect existing and future quarries from encroachment of non-compatible land uses such as urban expansion and rural lifestyle developments, thus reducing the potential for reverse sensitivity effects to arise.

The issue is important, as Auckland Council don’t seem to be protecting our quarries – like the Brookby, Hunua and Matakana quarries – from new incompatible land uses nearby.

AQA raise the spectre of other conflicts too. They believe the level of demand for aggregate created by the government (and opposition’s) plans can only be met if environmental safeguards are removed:

The AQA was disappointed with the status given in the Government’s 2019 Resource Strategy to the No New Mines on Conservation Land proposition… recent work by GNS Science has identified that 20-32% of future hard rock reserves are situated on DOC land…

The AQA is greatly concerned that the proposed National Policy Statement on Indigenous Biodiversity (NPS-IB) would require territorial authorities to “avoid” in any subdivision, the use and development of land within a Significant Natural Area (SNA). This would preclude quarrying over a large proportion of New Zealand. Currently 45% of potential aggregate land is classified “indigenous vegetation”…

And presumably in response to the National Policy Statement on Highly Productive Land, the AQA state:

site restoration can result in the delivery of land for future primary production or valuable new habitats, contributing towards national biodiversity targets and wider ‘net gain’ ambitions. In many regions of New Zealand, quarrying is the most highly productive use of land for primary production.

Clearly, further opening up the environment to exploitation will conflict with the values of many New Zealanders:

Seven out of 10 Kiwis are keen for New Zealand’s economic recovery from Covid-19 to be a green one

Does Auckland Council recognise the need to reduce aggregate use?

Council is required to follow guidelines in its decision-making such as:

Ensuring prudent stewardship and the efficient and effective use of their resources, in the interests of the district or region the council represents.

Taking a sustainable development approach (thinking about the social, economic and cultural interests of people and communities, the need to maintain and enhance the quality of the environment, and the reasonably foreseeable needs of future generations).

At one of the webinars about the Emergency Budget, I asked the question:

Why did Council continue to sign contracts after declaring a climate emergency, that were clearly going to increase transport carbon emissions, such as for new and wider roads? Did Council’s resiliency planning not highlight this as a risk?

The answer – from one of The Forty Decision-Makers – showed that new roads were legitimised, despite the climate emergency, because we need aggregate:

if you think of all the concrete that is in the CBD, that is in the suburbs, north, south, east and west 88% percent of that concrete comes out of… Franklin in the south. That aggregate is currently going to be between 12 and 15 million tons this year, depending on COVID. And it’s transported by trucks… on some of those new roads such as Mill Road in the South. That’s what it’s for. All those four big quarries in the south connect the Mill Road within a maximum of 25 kilometres…

That’s gorgeously circular, isn’t it? We’re paying princely sums for roads in order to be able to transport aggregate. The aggregate needed, of course, to build the roads.

Of course, the roads will cater for more than just trucks. The answer went on:

And new growth areas of Drury all require transport links for people on public transport, walking and cycling. But they also need to move goods and services.

So Council recognise the sprawl will induce traffic, meaning long travel distances – not just for residents, but for all the people who visit them and service their needs. Sprawl puts our average travel per capita up considerably.

The Councillor who gave this answer is a benevolent man, genuinely trying to achieve a better city of opportunity for our children, but the remaining part of his answer then deteriorated into misunderstandings about the interplay between environment and economy. Before we can help him move into a better climate understanding, he needs to see how he’s been:

Captured by The Political Economy of Car Dependence

Mill Rd requires political justification because it is a large, expensive, publicly-funded project, and each of the main strategies of legitimising road building has been used to provide this justification. (See my post The Political Economy of Car Dependence for context):

Council:

• say Mill Rd is necessary to accommodate our growth, including the traffic it’ll induce and the trucks needed to carry the aggregate. (Strategy 1a)
• say Mill Rd is necessary to stimulate the economy after Covid. (Strategy 1b)
• presumably believe car-based sprawl developments are preferred by Aucklanders over a quality, compact city where amenities are close and traffic volumes are low. (Strategy 2)
• claim Mill Rd is important in providing access to employment… a critical factor in improving economic productivity. (Strategy 3)
• say Mill Rd is required to remediate current congestion levels. (Strategy 4)
• defer to the “technical expertise” of the Supporting Future Growth team – despite modelling and business case processes biased towards road-building. (Strategy 5)

Once we strip these myths and excuses away, the rationale for the Drury sprawl echoes that of the Garden Villages in the UK, (see Building Up or Out):

Sometimes it seemed that the location of a new garden community was actually chosen because it would help finance a new road or better junction.

To achieve a greener, less aggregate-hungry economy, we need the market to assist our goals, by ensuring:

• business cases for roads include the true cost of the aggregate they use, including its transportation and environmental costs,
• quality compact urban development is rewarded in the marketplace for its prudent use of aggregate,
• recycled aggregate is more economically attractive for construction than freshly-quarried aggregate is.

A critical step is internalising the transportation costs of moving aggregate. The quarries themselves should pay for the maintenance and improvement of roads to the quarries, then pass this cost onto their customers. Instead, it seems that the cost for these roads is being imposed on all of society, swallowing funds we need elsewhere, pushing rates and taxes up, while failing to provide cost incentives to minimise the use of freshly-quarried aggregate.

So if Council woke up to their capture, what would they do about aggregate?

Planning for both aggregate conservation and climate change means Council need to:

1. identify our aggregate reserves and ensure we don’t encroach on them with inappropriate land uses such as lifestyle developments or urban expansion,
2. provide for future generations, by conserving well-located supplies and leaving a legacy of infrastructure with a low maintenance burden,
3. reduce our aggregate needs so that we’re not forced to haul aggregate into the city from a distance or quarry in precious environments.

Thus they need to:

1. halt our road expansion programme,
2. go up not out, by halting sprawl. (The National Policy Statement on Urban Development will remove some barriers to going up),
3. put the cost of maintaining quarry roads onto the quarries themselves, including any roading expansion they require.

Above all Council needs to acknowledge the Political Economy of Car Dependence doesn’t serve us well, and put in place an overt programme of action to address the multiple ways they have been influenced by it in their planning.

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