Wind turbines are a strong net-positive for aquifers, and in some jurisdictions are a direct contributor to aquifer volumes. They help reduce global warming and its attendant issue of drought and warming which causes environmental damage to wetlands. They help reduce air pollution which causes acid rain leading to deforestation. They help reduce air pollution that ends up directly in the water.
Concerns about wind turbines and aquifers fall into three categories, but these are overstated
- Wind turbine construction can damage habitat that filters water and directs it to aquifers
- Wind turbines could disturb fragile ecosystem around and in marshes
- Wind turbines could leak lubricants into ground water
These concerns are minimal compared to alternative sources of electricity
1. Potential habitat damage
Concerns relate to blasting of ridge lines, construction of roads and creating multi-acre construction sites. Modern wind turbines are significantly dispersed; at most they might take up 1% to 2% of the land when operating and impact slightly more during construction. The additional runoff concerns are statistically insignificant during operation. During construction, there would be some additional soil in local streams, but it would be filtered by the normal means and would represent an insignificant additional load. This study by the New Zealand Department of Conservation confirms this. By comparison, it is worth noting mountain-top removal coal mining which is much more destructive than dozens of wind farms.
Wind turbine direct impacts on habitat are insignificant and do not pose a danger to local aquifers.
2. Potential wetland ecosystem disruption
Some people have been concerned about the impacts of wind turbines on marshland and the birds which flock there, especially in more arid parts of the world such as Texas. Research into avian impacts just doesn’t support this as a significant concern.
Petterson (2005) recorded only one collision of a sea duck from about 2 million migrating past a Swedish offshore wind farm, while Fox et al. (2006) used radar studies at Nysted to predict a collision rate of 0.02% (i.e. a 99.98% avoidance rate) for 235,000 common eiders migrating past that site,
Given the wide spacing of wind turbines and the observed reality of waterfowl avoiding wind turbines, it’s unlikely that this is a major concern in most places. It certainly doesn’t make sense to put a wind turbine directly in a sensitive marsh, but that’s hardly a likely scenario.
By comparison, it’s worth noting that acid rain is heavily contributed to by coal power generation, with significant environmental impacts.
Wind turbine disruption of marshes and the birds which inhabit them isn’t a significant concern, and certainly not to the water table.
3. Potential lubricant leaks
There have been incidents where 50-80 litres (12-20 gallons) of lubricants and chemicals have been spilled in the construction of wind turbines. And there have been rare and isolated incidents where wind turbines have sprung a lubricant leak from their transmissions. These incidents are lumped with situations where tens of thousands of liters or more of oil or lubricants are spilled in train accidents, oil pipeline breakages or oil tanker accidents. They are further lumped with brown site remediation where gas stations have sat for decades with gasoline leaking into the surrounding soil.
These situations are statistically at the opposite ends of the scale. Any claim that wind turbine lubricant leaks are on the same scale as fossil fuel generation impacts on ground water is gross exaggeration. Similarly, concerns about the concrete bases of wind turbines somehow being a vast environmental intrusion are overstated as well. The concrete base requires about 250 cubic yards of concrete, or enough to build about six modern homes. This is not an overpass’ worth of concrete, or a parking lot, or a coal plant. Full lifecycle cost analyses of wind energy which include the concrete used in construction show that wind farms have the best CO2e per MWh of any form of generation.
For comparison, here are real aquifer concerns that people are concerned about:
Potential sources include industrial spills, tanker spills, fertilizers, pesticides, or just about anything someone pours down a drain that leads to a septic tank. For the most part, typical septic tank effluent is not the primary concern.
Wind turbines don’t make the list, for obvious reasons.
Obviously the more water a particular form of generation requires in the production of electricity, the more opportunity there is for that water to be contaminated. As such, it’s worth noting that in full lifecycle analyses by the California Energy Commission, wind energy uses 1/600th of the water of nuclear generation and 1/500th the water of coal generation per kWh.
By comparison, here’s the impact of an oil pipeline leak.
Wind turbines have almost no ability to contaminate aquifers even in disastrous circumstances.
Where does this leave us?
Wind energy is displacing fossil fuel generation that is harmful to aquifers and groundwater. Concerns about wind farms and water are misplaced.