Stormwater runoff has become a common problem for urban areas today. What is it? It is precipitation (from snowmelt and rain) flowing through the land. It might infiltrate the soil, discharge into water bodies, streams, drain inlets, or re-evaporate into the atmosphere. In the environment, precipitation is usually absorbed by the plants and trees or percolated into the ground, resulting in good water quality and stable stream flows. But all of this changes drastically when it comes to the built environment. Rain falling on rooftops, driveways, lawns, or patios runs off the surface faster, accumulating the pollutants as it flows.
Why is stormwater runoff a problem?
If the stormwater runoff is not managed properly, it can be a host of multiple problems, including:
Effects on the environment
- Flooding. The stormwater runs off driveways, roofs, and lawns, large volumes of it reach the streams quickly, which causes their level to rise and result in floods. It was supposed to be a natural and steady rise. When impervious surfaces exist, the threat of floods is more severe, damaging the people of an area and their property.
- Pollution. The world has been facing the problem of pollution for years, and it has shown no signs of reducing anytime soon. It is, instead, getting out of hand with each passing day. Many things contribute to the pollution rise, and stormwater runoff is one of the many. Let’sLet’s take a look at how. Running stormwater takes up many pollutants like fertilizers, oils, pesticides, trash, animal waste, dirt, and sediments along the way. These pollutants mix up with stormwater and find their way into the local streams and valleys untreated, thus, polluting them in a big way.
- Erosion. How important soil is, is nothing to talk about. Everyone knows about this. But what one might not know is that soil erosion is also caused by stormwater runoff. You heard it right. Stormwater flows rapidly with unusually high volumes of water, the power of which can cause the erosion of bank streams. It can damage properties located at the streamside, create risky situations, and damage aquatic life, including fish and other habitats. This erosion is also a source of sediment pollution.
Effects on the animals
Environment and wildlife are two things that are connected when pollution is the center of the talk. As it is obvious how aquatic animals can be affected by this phenomenon, what about the land animals. Well, they too are affected by this. The stormwater often accumulates a lot of debris and pollutants, traveling towards many animals’ natural habitats. Floods can affect terrestrial animals as they are not cut out to survive in water for long. And also, land-bound animals use the lake or stream water to stay hydrated. If the water is harmful, it can result in their deaths. So, you see how aquatic or land-based animals are not unaffected by the stormwater runoff.
Effects on human beings
Now you may be wondering, okay, it is clear to see the phenomenon’s effects on nature and wildlife, what about the people in general? Is there any visible effect on them? The answer, yes, there is. Floods caused by stormwater runoffs put the people and communities in danger. Though it may not sound extreme, some floods are very powerful, damaging properties, life, and drowning people.
The damage caused by these floods impacts the financial health of an area as the damage takes up a lot of money to clean the mess created. The surface runoffs can also affect the business, like recreation, fishing, shellfish, and tourism. The overall revenue of an area, thus, faces problems.
It also demands increased costs to treat the water from various water bodies. If this water is not treated effectively, it can lead to widespread diseases in an area.
Now that it is clear how exactly stormwater runoff is a problem, let’s look at the various factors that, knowingly or unknowingly, contribute to this.
Factors contributing to the problem
The primary thing that you need to know is what exactly causing the stormwater runoff. If you look closely, you will find that there is not only one factor that comes into play here. There are a lot, and some of them haven’t even been noticed by people for a long term. Take the example of the daily litter caused by everyone, which shows its consequences at the later stages. The litter spread on the ground ends up in streams.
Stormwater takes the residual pollution left by construction activities, pets, cars, dumping, fertilization, and much more. It can be said there are so many people around who are blissfully unaware of the fact how their actions are posing a great threat to the environment.
The urban infrastructure is one of the major factors that hugely contribute to this problem.
As discussed above, soil, trees, and other natural vegetation help in less stormwater runoff. But the area covered under these is reducing fast, and all of this is because of the buildings, roads, and other construction works taking place. It prevents the water from coming in contact with the soil. The water thus floods over the concrete roads and blocks of cement, ending up in streams. If this is not the case, it enters the sewage system and is finally diverted into the rivers and other water bodies.
Whatever the case is, both results are the same, and there is nothing done about it.
What can be and needs to be done?
Fortunately, the problem of surface runoff has caught the attention of scientists, and it has been researched and deciphered for years now. The main thing that needs to be focused on is the infrastructure. You caught that right.
As technology developed with the changing world, urbanization and gray infrastructure have probably peaked, which is not worth worrying about. How exactly infrastructure plays a role will be discussed below here.
Overview on infrastructure
The infrastructure of a place is basic structures such as roads, bridges, water lines, buildings, and sewer systems, which are vital for the healthy functionality of any community. The infrastructure must be maintained, repaired, and replaced (if needed) regularly to function at its best.
Stormwater runoff has become one of the leading problems dancing on the heads of everyone. Community leaders are faced with how to make the best decisions to manage the stormwater runoffs.
The conventional “gray” stormwater infrastructure focuses on moving the stormwater away from the modified environment and includes drains, gutters, piping, curbs, and collection systems. It collects stormwater from surfaces like parking lots, rooftops, roadways into a piping system that discharges this stormwater into local water bodies. But, is it the right way to deal with this? No, of course not; it doesn’t do any good to anyone and is outdated, according to the needs of today. Green stormwater infrastructure is what the need of the hour.
What is green stormwater infrastructure?
Communities are trying to become more resilient by adopting green stormwater infrastructure. It is a structure designed for filtering and absorbing the stormwater right at the place it falls. It manages the water cycle as naturally as it can. It enhances the quality of life and community safety.
So basically, it involves planting trees and restoration of wetlands instead of building water treatment plants. It is the use of various measures to use the trees and soil system, permeable surfaces, harvest and reuse of stormwater, and landscaping to store and filter the stormwater. Thus, reducing its flow to other water bodies through sewer systems.
Elements of green infrastructure
Green infrastructure can be knitted into a building, community, and broad landscape at various levels. It includes a range of different practices, including the following:
- Rain barrels against houses
- Planting rows of trees in major streets
- Greening an alleyway
- Creating rain gardens and green roofs
- Creating wetlands near residential complexes
- Protection of open and large green spaces
All of these can help to enhance community safety and health alongside reducing the effects of stormwater runoff.
Methods for practicing green infrastructure
The following are some more methods that one can follow to reduce the effects of the stormwater runoff to almost zero:
- Downspout disconnection. This practice includes rerouting the rooftop drainage pipes to drain the rainwater into cisterns, rain barrels, or other porous surfaces. It can be used to allow the stormwater to seep into the soil. It can benefit the city dwellers with combined sewer systems.
- Rainwater harvesting. A practice that you have heard about since childhood. It reduces stormwater pollution by accumulating the rainwater for use later. The system includes:
- A backyard rain barrel
- Ground-level pits
- Commercial cisterns
- Even nets to capture fog and dew
These systems are implemented and used on a global scale.
- Planter boxes. These are urban rain gardens having vertical walls with either closed or open bottoms. They can be seen in downtown areas and are ideal for limited spaces. It is a wonderful way to beautify the busy city streets.
- Bioswales. These can be found in parking lots and curbs and use mulch and vegetation to filter and slow stormwater flow.
- Green parking. Green infrastructure can be combined with parking spaces. Installation of porous pavements, bioswales, and rain gardens along the parking perimeter. On installation, these elements can significantly reduce the heat island effect with enhanced walkability.
- Urban tree canopy. Trees are the best absorber of stormwater; there is no denying the fact. That’sThat’s why many cities have set goals to restore the lost tree canopies. Everyone from homeowners to community groups and businesses can help maintain the urban environment.
- Green roofs. Roofs are covered in vegetation and plants to infiltrate the stored rainwater. These are cost-effective in densely populated urban areas.
Why green stormwater infrastructure?
Why should one replace the gray infrastructure with green infrastructure, you may ask? Here are some reasons that can make that crystal-clear:
- Can’tCan’t waste money. There is no use in wasting money on less reliable solutions. Money spent wisely on multi-purpose solutions with more benefits is the money spent well. The saved money can be invested somewhere else.
- Nature is the best. Rivers, wetlands, streams, forests, and floodplains work the best to provide clean water and protection from flood, thus are an essential component in water infrastructure. If you invest in green infrastructure, you will have a safe and healthy lifestyle with access to naturally clean water.
- Community safety and recreation.As much as the safety of the community, their fun and enjoyment are also necessary. The green infrastructure offers the perfect place for adults and children to spend time with nature and know about it more. It also provides a beautiful view of the community.
Effects of green infrastructure on jobs and economy
The green stormwater infrastructure projects create many jobs in different sectors, including landscaping, plumbing, engineering, design, and building. It also helps in supporting the supply chains and thus the connected jobs with manufacturing sectors like the permeable pavements, rainwater harvesting systems, and roof membranes.
Many countries are using the power of green stormwater infrastructure projects to create jobs while improving their economy sustainably. Missing out on the opportunity of green infrastructure can be a big failure.
The new vision
Water is an essential natural resource, and every drop of it counts. Today, world leaders are at the crossroad of how they choose to manage water wisely. The use of traditional infrastructure is not being discarded here, it will keep playing its role, but it demands a line of thought from everyone. Is it enough to use a static solution focused on a single goal only?
It is high time to change with changing times and combine the traditional infrastructure of the 19th century with the green infrastructure of the 21st century to get the most out of them.