Interview: There’s only One Water – CEO David Sparke on rainwater harvesting, and assisting natural stormwater treatment processes.

I was recently fortunate enough to visit OneWater’s ( CEO, David Sparke at his warehouse offices in French’s Forest, Sydney. I got to interview him, meet his team, and chat over a cup of tea on a brisk autumn day. I also took a peek at some of OneWater’s primary and secondary stormwater handling technologies and the engineer in me was impressed by their simple practicality and ease of maintenance. David himself was a keen advocate of stormwater treatment and harvesting, passionately sharing his views on many topics relating to development, planning and water quality in Sydney and surrounds.

Below is the transcript of our interview, annotated from its original raw format for better readability:

Who is David Sparke, and what work does OneWater do?

M: I am here with David Sparke of OneWater. David is the CEO and has been very generous in his time to sit down with me today to do this interview. Let’s start.

D: Thanks, Marlene. David Sparke is my name I’ve been involved with OneWater since 2002 when I established the brand. OneWater was based on the fact that there is only OneWater resource, regardless of how we interact with it in its various forms.

I have had a lifelong interest in water and an association with water. I started off my career with Sydney Water or what was then known as MWSDB, working on constructing gravity mains for sewers in the Northern Beaches. I then continued my career in a bureaucracy before retiring from that to do some undergrad and postgrad studies in international marketing. I eventually came back to water, and built up a business based on management and transfer of water. This evolved into rainwater harvesting, which became topical around the mid to early 2000s when political and media goodwill drove rainwater harvesting projects. The approach was to give people incentives to install rainwater harvesting systems, principally in the domestic space. The introduction of community water grants further created an incentive for schools and community centres to install harvesting systems. This period was quite successful for us.

Since then, Australia has experienced the GFC, along with a decline in housing starts, which shrunk the construction sector, and substantially affected water businesses. We restructured into finding solutions that promoted water quality and water as a resource. At this time I got involved with Austrade on a few water missions to the United States and into China, and gained a good understanding of the water markets and conditions that exist over there. Australia is highly regarded due to our experience from the 2000s, so we’ve got quite a good marketing position and global sense to drive the water market globally.

So what has happened to our attention on water in the last decade?

D: I think water has been overtaken to a large degree by the focus on energy but they do work hand in hand – there’s a Nexus between the two and water is now becoming a little more prominent again on the basis of shortages.

OneWater’s processes avoid adding chemicals or other elements into the water, which is often part of many traditional treatment systems, but which further contaminate the water. We view nature as the ultimate water treatment process and we have to support nature as much as possible to allow the normal processing of water that occurs in natural systems to happen. The OneWater system allows contaminants from say industrial sites (including roads) to be managed by various means in diversion, segmenting small areas and independent treatment – often including an oil/water coalescing system.

M: Thanks David. It’s fascinating that you highlighted Australia’s prominence at one point, ahead of many other developed countries in terms of rainwater harvesting and treatment. You’re able to draw parallels between the water quality in Australia and places in Europe and elsewhere. How do you feel we compare now post GFC [Global Financial Crisis]?

D: Well it’s my view but I think we’ve substantially fallen behind in a lot of aspects in at least the last 10 years. In Australia now I think the emphasis seems to have shifted to landscape architecture as the solution for water quality and the ubiquitous GPT, which in my view is misconceived as a primary treatment device, it’s no more than a separator, and that’s not sufficient for good water quality. It doesn’t sustain ecology – which, when discharging to the waterways, is often the benchmark by which we can say that we are treating water well.

M: Just for our audience could you expand a little on the GPT acronym?

D: GPT stands for gross pollutant trap, which in municipal infrastructure is the primary go to device for stormwater treatment. Ultimately a pits and pipes drainage solution does not adequately address water quality – it’s basically handling the effects of water flow on the surface. 

During a peak stormwater event, the GPT may not be able to cope, or it blocks up, and no treatment is done. Many GPT’s also claim to capture hydrocarbons but the designs and high velocity flows makes this highly improbable. GPT’s also fail to reduce the soluble contaminants that result due to other major issues of algae contamination, oxygen depletion, anoxic reactions with the captured organics and rotting litter with water quality significantly degrading in a relatively short time. The OneWater systemized product solutions and engineered design prevent this by treating all the flows; and by regularly maintaining reset the devices after a storm water event, this approach ensures superior potential for contaminant reductions before release to waterways or wetlands. This systemized treatment train provides support for nature to complete the tertiary treatment. 

Photo by Oliver Swinburne on Unsplash

The OneWater way of handling stormwater

M: Thanks. So OneWater gets involved in rainwater harvesting, stormwater treatment as well as treatment and transfer packages for conventional sewage treatment. You also provide the engineering Design Services associated with these products. Could you give us some examples of some of OneWater’s more notable projects here in Australia or elsewhere?

D: We had a major position in the Sydney market for schools and community projects where we did roof capture and storage, to be used for services such as toilet flushing, air-conditioning, and maintenance needs. These were successful projects that led me to believe that our solution needed to look at the rainwater that ends up on the ground where the majority of our water falls. Roof water capture is convenient as a cost effective solution, but when water ends up on the ground it picks up any contaminants in the catchments. 

M: Yeah that’s a very good point actually because if we’re not treating the diffuse sources, the problem just grows and grows as water travels through the catchment. Someone once described it to me as being like death by a thousand cuts by the time it gets out to the bottom of the catchment.

How can we improve the way we manage stormwater in Australia?

M: You recently gave a great presentation at the Australian Water Association seminar on valuing liveability. What do you see are the opportunities within Australia in particular in our Urban centres for improving the way we currently manage our water and wastewater?

D: In that presentation I had a couple of outlines of the Sydney Basin and it doesn’t take a lot of analysis to see that we don’t have a holistic plan for managing our water sources and I don’t think that that will contribute to  Sydney’s liveability into the future. We’ve got some major projects like just outside here – a $500-million project, but all that’s been installed is drainage. All the vegetation has been cleared to facilitate the infrastructure in place yet the whole ridge has been drained, and it doesn’t to me indicate any focus or any commitment to environmental protection and water quality discharge.

M: That’s a really interesting point David, there’s a lot of land clearing going on in Sydney but also in many other large urban centres around the world. What do you think is the key message here regarding the way we have to deal with storm water and also build new infrastructure?

D: Groundwater represents potentially up to 80% of our available potable water. We’ve also got surface water, and we’ve got harvested water. We’ve got sewage treatment plants which discharge into inland rivers – the Nepean Hawksbury and South Creek. That river system surrounds the Sydney basin. We’ve got a series of ocean outfalls with only screening before release. That water is still a resource if we treat it properly. 

Harvested water can be retained until it is needed.  If a storage volume of at least 100 cubic meters were available there would be a reserve of water to utilise. This form of water conservation ensures that stormwater is not wasted.

M: Hence the term OneWater because it’s the one resource.

D: It’s the OneWater and we have support nature in doing the tertiary treatment, and for the sustainability of our natural water resources. 

Photo by Aman Bhargava on Unsplash

Integrating water ideologies

M: You’ve done a fair bit of work, David, in overseas markets as well. How does Australia compare in terms of adoption of sustainable technologies, as well as the government drive to roll out sustainable technologies, or any other differentiating factors that you’ve noticed?

D: We’ve had a few water missions into China. China has their sponge city ideology, which relies on infiltration technology. In my view this is only a starting point in looking at a more holistic solution. China has got 3 different environmental (climatic) conditions, including a relatively a dry central area, and a tropical south. That presents challenges for an ideology that spreads across the country.

In Australia, we`ve got WSUD (Water Sensitive Urban Design), the USA has LID (Low Impact Development), the British and Europeans have SUDS (Sustainable Urban Drainage Systems). Although largely similar, we haven’t got a benchmark that everybody can follow and achieve.

There was a NSW state government urban growth discussion paper on water quality, setting vigorous contaminant reduction standards, but the industry was not ready to deviate from the status quo. In water conservation terms, for example in NSW, an original target of 40% reduction in the use of potable water from mains source has exceeded expectations over a 10 year period and it has now been moved to 50%. I’d like to see the aspirational targets for contaminant reduction set for industry, which industry can then plan and attain over time.

We need strong leaders or champions in the stormwater market to push for better water quality and for maintaining the environmental conditions for the ecology. 

Reasons for investing in stormwater quality

M: I think you make a very good point there about our attitudes to stormwater. I was at a WSUD conference earlier this year where somebody mentioned that they worked for the Hong Kong drainage department, and that we need to stop thinking about stormwater as something that needs to be drained away, but rather a resource that we need to treat and make better use of.

To those that are still wondering whether or not to invest in water harvesting or urban rainwater treatment or landscaping, could you go through some of the pros and cons?

D: Stormwater pollution and qualitiy needs investment, and it’s a good market. Major infrastructure projects often treat stormwater as one of the 8 or 10 elements of the project and it consequently does not receive proper prioritisation. Collaboration by an astute investor with our SME creative skills could greatly benefit many projects. I’ve created a conceptual design to improve water quality and back that up with having product solutions that are flexible and not necessarily restricted to projects that are civil works. With a good investment regime, Australia can pick up a lot more of the leadership that’s needed in stormwater and help drive that. As I say there is a substantial market there.

I think I’ve created an approach that can be implemented and I think it can create a strong process model, but I do need some support. As an SME it needs the right investors to do that, and collaboration to pick up and drive good outcomes for stormwater.

M: So correct me if I’m wrong but basically what you offer is a better long term solution that utilises natural processes as well as using a few engineered products as well?

D: The basic concept is that we can’t get the value and the amenity out of water by channelling everything right through the catchment, right through to the bottom of the catchment before we do anything about it. My concept starts at the very top of the catchment so that we’ve got good quality water, we’ve got a fantastic urban amenity and the use of water and the waterways are protected all the way along, and it just seems logical that the top of the catchment is where we need to start. The products that I’ve designed facilitate that catchment issue and can assist in creating our liveable cities of the future.

Last words from OneWater

M: So what’s your vision for OneWater going into the future?

D: I’d like to see a new approach to stormwater management. I use the term harvesting to the whole of the process. The process needs some hydraulic residence time for nature to do it’s work but we shouldn’t be using stormwater and our waterways as a disposal channel. We have to remove those contaminants to a land-based facility and view them as resources that can metamorphose into alternate products. I’d like to set up some collaborations to get some investment and lead stormwater to where it needs to be – positioning it for sustainability and resource resilience.

M: You’ve shared a lot of really good insights with us David. Are there any last things that you’d like to add?

D: I think we can easily apply the product design that I’ve created. It’s well thought out. It’s science-based. It’s materials based. It takes account of the drainage and the regulations and the guidelines for water quality and I think we need to get beyond the heavy engineering concrete pits and pipes and see the value of alternate solutions.


### Author’s note: The Nexus Journalist receives no commission, income or royalties from the publication of this interview, and holds no vested interests in OneWater’s products, services or other offerings. Views and opinions of the interviewee do not necessarily reflect the author’s views ###