We may hear the word ‘stormwater’ often enough, but how much do we really understand about stormwater? Where does it come from and what does it consist of? Where does it eventually go?
Stormwater can be defined as water originating from precipitation and snow melts. Stormwater can then either join or run off a stream, water bodies, rivers, evaporate from the ground surface, or it can be captured underground as groundwater through infiltration.
Stormwater is relatively plentiful and is easy enough to capture or store, and while it can be used for some general domestic and commercial applications in its raw form, it is best practice to treat it first. The safest and most environmentally friendly way of dealing with stormwater is to have it treated immediately after capture, prior to it entering the main municipal waterways. The exact treatment method can vary depending on where and how the raw stormwater is captured and what its intended use is. For consumption by humans or animals, the water must be filtered from large contaminants, purified and any bacteria destroyed by means of UV sterilisation. If it is to be used for irrigation, less filtration and sterilisation is required – often a simple grate or mesh filter is sufficient to remove large contaminants such as leaves or other vegetation. Where the stormwater is collected and how it is moved can have a significant effect on how much treatment is required before it can be assessed as safe for consumption or discharge.
For instance, if the stormwater is collected from an agricultural area, the runoff water will most likely have high levels of natural nutrients and may be processed and treated quickly. Whereas, if it is collected from an industrial area, then the runoff is likely to contain varying levels of oils, metals, chemicals, or other foreign objects, some of which can be extremely dangerous to the environment.
To help manage this issue, complex stormwater treatment, storage and transfer systems may be required to efficiently handle the raw stormwater. Stormwater pumps play an important role in these functions, where they are used for transferring large volumes of water quickly from one place to another, often out of storage tanks and into main pipelines.
The first level of treatment the stormwater will go through aims to remove all the coarse sediment and pollutants, this can involve items like cigarette butts, plastic bags, small pieces of plastics, straws, paper products, which, if left untreated and not isolated, could eventually end up in our oceans and waterways causing immeasurable damage to our wildlife. This is due to the fact that plastic items and pollutants are generally non-biodegradable and are oftentimes fatal to our marine life.
Within the second level of treatment, you will see the removal of oils and greases from the stormwater. Higher levels or oil will generally come from stormwater catchment areas near car parks, and can have an adverse effect on the stormwater pumps if left too long untreated.
Finally, the tertiary level of treatment is absolutely vital for the removal of chemicals like nitrogen and phosphorus, along with heavier metals like lead and copper. The reason for this is that the introduction of heavy metals can cause the water to begin to turn toxic, which again can have an adverse effect on the local wildlife.
Although ‘stormwater’ is a common phrase, as above, there are many different aspects to consider when dealing with stormwater, each of which can affect your stormwater pump choice. If you have any questions relating to stormwater and how it should be treated, or are unsure which pump will best suit your needs, feel free to contact our professional team at Aline Pumps, and our friendly team will be more than happy to assist you.
