Stemming the flow

The latest report on Christchurch's drinking water offers glimmers of hope among the grim reading. Dominic Harris sits down with new council water boss Helen Beaumont to find out how she plans to turn things around.

The last six months have been intensely uncomfortable for many at Christchurch City Council.

In the middle of working out how to rebuild a city devastated by earthquakes, late last year authorities were given shocking news – what they thought was a perfectly secure drinking water supply was in fact widely compromised.

The situation was triggered by the tightening of regulations in the wake of the Havelock North disaster of 2016, when polluted bores left 5500 ill and four dead.

A re-examination of Christchurch's water infrastructure under a stricter interpretation of rules found that more than 100 below-ground well heads did not meet safety standards, with pump stations vulnerable to contamination from surface groundwater.

What had been deemed acceptable for years was suddenly not good enough, presenting civic leaders with arguably their biggest challenge since the 2011 earthquake – and one they apparently had no way of foreseeing.

READ MORE: * Cost to keep Christchurch's drinking water safe spirals to almost $40 million * Top council strategist brought in to steer ailing chlorination project into calmer waters * Council indicates no Christchurch well heads have been upgraded after drinking water compromised * The South Island towns (and city) fighting chlorinated drinking water * Christchurch City Council making slow progress on repairing 102 well heads * Water expert sacked from city council contract after raising concerns over public health * Christchurch water supply 'at risk' from unmonitored bores * Christchurch mayor wants chlorination levels reduced after public outcry * Christchurch drinking water to be chlorinated for a year as councillors approve plan to keep it safe

Caught unawares, many residents feel the council has stumbled through the last few months as it has scrambled to get to grips with the scale of the problem.

Councillors quickly announced a programme of temporary chlorination and repairs, but the way it has been handled has left a bad taste in the mouth – from a public backlash about taste, smell and the health impacts from chlorine to disquiet about mixed messages and muddled communication.

What was thought might cost a few hundred thousand dollars and take less than 12 months has spiralled to tens of millions and years of intense work ahead as the complexity of the problem came to full light.

Cue the council drafting in its top strategist, Helen Beaumont, at the start of June to steer the work programme to calmer waters.

In between getting her head around flow rates and bore hole depths, this week she accompanied Stuff to pump stations in northern Christchurch, happy to point out weak spots in gloomy well chambers and discuss the merits of air valve positions with engineer George Chapman.

And where others have previously been reticent to speak out, she is happy to make some frank admissions.

The improvements ahead will be a "massive task" that will take "some years", she says, while the initial cost estimates and timeframe outlined in January were "miles off".

She concedes the council "has not communicated as well as it could have done" over certain issues.

And while she is confident in the plans to have chlorine out of the water by next May – 12 months from when the treatment was started in full – she admits she cannot be adamant.

"I can't put my hand on my heart today and promise that we can do it, and that's because we're still working through the options of the programme and the timelines for all of those options.

"But it remains the target."

WHAT'S IN THE PIPELINE?

Christchurch's water supply is drawn through 140 wells at 53 pump stations. Some of the infrastructure is old – the oldest well dates back to 1924 – and before the earthquakes most wells were built below ground.

Today there are 104 below-ground well heads and 36 above ground in regular use, with pump stations usually a mix of the two.

But under the more stringent adherence to standards those below ground are regarded as at risk of contamination, while some of those above need repairing.

Some issues are minor – a new grille needed over an air vent or a cable to be sealed – but others, such as raising well heads or drilling new ones, are serious undertakings that could take up to a year.

Improvements to wells below ground have been carried out at 22 pump stations since last year, but they are still not up to the new interpretation of the standards and so have not been signed off as secure.

Four other stations containing 11 wells above ground, at New Brighton and South New Brighton, at Harewood and near Prestons, were always secure and unchlorinated.

But a huge task lies ahead to meet the ultimate goal of raising all the wells above ground.

The council has developed a three-pronged attack to get work going and remove chlorine from the supply in the promised time – fixing wells that need upgrading, prioritising pump stations with unchlorinated above-ground wells so other chlorinated ones can be isolated and turned off, and considering alternative disinfection methods such as UV or ozone treatment.

The first tranche of work is well in hand, with minor repairs and raising well heads at seven pump stations to the north and west of the city, at which most wells are already above ground.

These should be "quick wins", Beaumont says, with clear costs and a timeframe for completion.

"That work will take place starting in July and finishing in May next year.

"Once we've got that work done alongside the four pump stations that are not being chlorinated now we'll have about 25 per cent of the supply across the city without chlorine."

But the lion's share of the improvements, to fix wells at 42 stations, still lies ahead – and there is little clarity yet over how and when that will be achieved.

"We've identified what the options are for at least the first half of those 42, but we're still doing some investigative work to determine what's the most cost-effective option for each of those.

"We do have an idea of what we're going to do, but we don't want to confirm exactly the strategy for each well head and each pump station until we've done some further work."

Potential solutions involve raising wells, alternative disinfectants and turning off wells below ground.

Other options include drilling entirely new wells; engineers are investigating whether 19 that tap into a shallow aquifer with question marks over its security need to be replaced with other wells that go into a deeper aquifer.

"We don't want to race into expensive remediation works if we decide we're going to replace those wells into deeper aquifers," Beaumont said, remaining tight-lipped over the timeframe because of numerous uncertainties.

Constraints on repairs include the availability of drilling contractors and how long work will take, and the number of wells that can be turned off at any one time while still maintaining adequate supply across the network.

It is here Beaumont feels the public may have a part to play, by restricting water use.

"If we can hold it to winter levels then there are more wells that we can turn off. We're going to do some modelling across the network so we have a much better idea of where we can do that.

"If we can reduce the demand then we don't need so many wells pumping to maintain the pressure."

TREATMENT OPTIONS

For Christchurch residents used to pure water, chlorination has been more than a shock. Many have complained bitterly of the taste and smell – sales of filters and bottled water have gone through the roof and the council reduced the dosage – and, more seriously, people have experienced health problems.

Unsurprisingly, removing chlorine as quickly as possible is a key goal.

"We will remove it progressively as we remediate or isolate well heads at particular pump stations. As you remove it from more pump stations there will be less chlorinated water going into the mains.

"If we manage to do it for all the pump stations within a pressure zone then those people will get no chlorine, whereas other people will get a bit more mix."

The four unchlorinated stations are also being leaned on to supply more pure water for the network, pipelines are being flushed and five pump stations – Lake Terrace and Thompsons, along with Burnside, Farrington and Grampian – could have chlorinated wells below ground switched off once repairs are done to above-ground wells.

Other options include using UV and ozone as alternative treatments, though they are expensive.

But Beaumont believes it could be more cost-effective to use these methods at some sites and put off raising well heads.

"The ultimate solution may change over time. For a particular pump station it might be that we put in UV disinfection for a period of years and then we either remediate the well heads or abandon that pump station and put in a new one."

One area remains slightly ambiguous – when chlorination should be gone by.

Mayor Lianne Dalziel said in January it would be 12 months, with councillors having to vote for anything longer than that.

Beaumont suggests the 12 months may be from the time chlorination actually occurred, meaning it could be May before the chemical is out.

SOARING COSTS

At a time when people would rather their hard cash was spent on housing, a stadium or repairing the cathedral, spiralling costs for the programme seem a certainty.

When the problem was originally uncovered the council thought a budget of about $1.4 million might be enough to fund the repairs and chlorination.

But as issues have become more complex, costs have exploded.

Up to $5 million is needed for repairs at the seven pump stations where work is imminent – the "quick wins" with relatively minor work.

Beaumont shied away from putting a price on the other 42 sites because options are in such early stages, but it seems likely it will run to tens of millions of dollars.

Her report to council last week suggested drilling a new well costs around $1m, and if the 19 wells in the shallow aquifer are replaced then the bill for that alone looks set to reach around $20m.

Then there are the treatment options. Chlorination is now costed at $2.25m for installation and another $1.29m a year to run. UV treatment being considered for 12 sites could cost between $21.6m and $86.4m and ozone treatment at one more could be $5m to $8m.

Irrespective of what happens, somehow the council will have to reach deep into its pockets.

Under its long-term plan to 2028 it has $35m for well head replacement and repairs. $25m of that is being brought forward so Beaumont can use it in the first three years, so along with the $3.5m available each year she will have the whole pot to use by 2021.

But any more would require council approval and public consultation to amend the plan.

An elephant in the room remains – the spectre of mandatory permanent chlorination, something the Government could enforce in its response to the Havelock North inquiry.

The council estimates this would cost $100m and $5m a year to run, but Dalziel has vowed to fight "tooth and nail" to keep this at bay.

A DROPPED BALL?

While the details of a final bill and the timeframe for work remain murky, it is clear they are likely to be high and stretch for years.

What remains unanswered, though, is whether anyone is actually to blame for all this.

Wells and pump stations are assessed every year by specialist engineers, most recently by Beca and until June last year by Pattle Delamore Partners, PDP.

These experts sign off on the security of the well heads, and reports go to both the drinking water assessor (DWA) – whose role falls under the Canterbury District Health Board – and the council.

The inquiry into the Havelock North crisis was highly critical of the Ministry of Health and the local authority for a softly-softly approach and failing to ensure policy was followed.

But the rules have not been re-written – they are simply being followed more strictly across the country.

If that is the case, the decision by the DWA in Canterbury to pull the secure status of Christchurch's wells reflects a tightening of those rules.

This would suggest the rules were not followed stringently enough before, and that standards were allowed to slip.

If the goalposts over standards have not moved, why was something that a year ago was good enough now no longer that? Did someone – the council, the DWA, engineers – take their eye off the ball?

Beaumont herself is not certain of the answer, but believes what constitutes "secure" is a grey area rather than a clear line that must be reached, an assessment reached by experts who evaluate sites individually.

"The specialist engineers who are assessing against those standards are interpreting them more strictly. When the standard says a well head has to be secure, it's what 'secure' means.

"It's not as simple as just not being up to standard."

Either way, a review into what has happened – likely in the coming weeks – may shed some light.

Meanwhile, the council appears to be embarking on a charm offensive to get the public on side, with a regular blog about the water improvement programme starting soon.

This week Dalziel and Beaumont, with chief executive Karleen Edwards in the crowd, spoke for an hour at a packed gathering at Christchurch's Smash Palace to explain the decision to chlorinate, update people on the progress of work and champion the city's pure water.

Referring to the Havelock North incident, Dalziel said: "What the whole thing has called out is that actually things have got a bit slack and lackadaisical in terms of signing things off, just ticking the box.

"And actually, we deserve better as a city. We actually need to have the ability to rely on our confined aquifer system to deliver unchlorinated water to our citizens.

"It's going to take some time to get to there, and we're keeping the pressure on."