Lately, we have been receiving a lot of calls from homeowners and businesses who have backed-up, overflowing downspout drain lines. Roof drainage is important for protecting your foundation or crawlspace. What’s going on here? As I posted a few days ago the PNW has more rain in the winters. The term “atmospheric river” often comes up in the media.
What is an atmospheric river and why are we experiencing them? Global climate change is the culprit . . .
An atmospheric river is a long, narrow region in the atmosphere that can transport moisture thousands of miles, much like a river in the sky. These systems are typically several hundred miles wide and can be up to thousands of miles long. They are a key feature in the global water cycle and are critical in bringing fresh water to certain regions, but they can also cause extreme rainfall and floods.
Climate change affects atmospheric rivers in several ways:
1. **Increased Moisture**: Warmer air can hold more moisture, so as the planet heats up due to climate change, atmospheric rivers are likely to carry more water vapor. This can lead to more intense precipitation events when these rivers make landfall.
2. **Altered Patterns**: Climate change can alter atmospheric circulation patterns, potentially changing the paths of atmospheric rivers. This could mean changes in where and how often these systems impact certain regions.
3. **Increased Intensity and Frequency**: Some studies suggest that climate change might lead to not only more intense atmospheric rivers but also an increase in their frequency. This could result in more frequent and severe flooding in areas affected by these systems.
4. **Snowpack and Water Supply Impacts**: In mountainous regions, atmospheric rivers can have significant impacts on snowpack, which is a critical water source for many areas. Warmer temperatures might lead to more rain and less snow, affecting water storage and supply.
5. **Ecological and Agricultural Effects**: The changes in atmospheric river patterns and intensity can have various ecological and agricultural impacts, from altering growing seasons to affecting ecosystems dependent on certain precipitation patterns.
Understanding how atmospheric rivers will change with global warming is an important area of climate research, as it has significant implications for water resources, flood risks, and overall climate impacts.
Ok, so then why is roof and downspout drainage so important? When I grew up in the 80’s and 90’s we used splash blocks in Wisconsin. Yes, your’s truly is a transplant, Splash blocks are those wedge shaped things you place under a downspout to direct water away from the foundation. They are ok for a small roof. However, when planning a new addition or new build that is larger than 1000 sq feet the building departments in Portland will require a roof drainage system. They want you to keep your water on your property. It could be an infiltration system – a dry well – or a bio-swale, rain garden or in some circumstances the sewer. Why is this? The reason is because the average roof sheds an amazing amount of water.
The average roof in the Pacific Northwest, with a size of about 2,000 square feet, would shed approximately 7,500 cubic feet of water in a year, given the average annual rainfall of 45 inches. This is equivalent to about 56,104 gallons of water!!! Historically in both Portland typically all of this water was drained into the sewer. So why is this a problem? Why would Oregon and Washington, Portland, want to change that? What gives?
Cities like Portland have moved away from allowing roof water to be drained into the sewer system for several reasons, primarily related to the management of stormwater and the impacts on sewage treatment:
1. **Combined Sewer Overflows (CSOs)**: In many cities, stormwater and sewage are carried in the same pipes, known as combined sewers. During heavy rainfall, these combined systems can become overwhelmed, leading to combined sewer overflows where untreated sewage and stormwater are discharged into nearby water bodies. By redirecting roof runoff away from the sewer system, the volume of water in these combined sewers is reduced, thereby lowering the risk of overflows.
2. **Water Quality Protection**: Directing roof runoff into natural areas or stormwater management systems, rather than the sewer system, can improve water quality. Rainwater can be filtered through soil in green spaces, reducing the pollutants entering waterways.
3. **Sustainable Water Management**: Cities encourage the use of green infrastructure, like rain gardens, permeable pavements, and green roofs, to manage stormwater sustainably. These methods allow rainwater to infiltrate the ground, replenish groundwater, and reduce the burden on the sewer system.
4. **Reducing Load on Wastewater Treatment Plants**: By keeping rainwater out of the sewer system, the load on wastewater treatment plants is reduced. This can result in cost savings and increased efficiency for these facilities, as they are not using resources to treat large volumes of relatively clean rainwater.
5. **Climate Change Resilience**: As climate change leads to more intense and frequent rainfall events, managing stormwater effectively becomes even more crucial. Separating rainwater from the sewer system is part of adapting urban infrastructure to these changes.
6. **Urban Flooding Mitigation**: Proper stormwater management, including redirecting roof runoff, helps mitigate urban flooding. It reduces the volume of water that must be handled by storm drains and sewer systems during rain events.
In summary, the political decision to redirect roof runoff away from sewers in cities like Portland is driven by a need to reduce sewer overflows, protect water quality, manage stormwater sustainably, reduce the load on wastewater treatment plants, increase climate change resilience, and mitigate urban flooding.
Why worry about the load on sewage treatment plants? The West Point Wastewater Treatment Plant in Portland’s Discovery Park experienced significant damage due to equipment failures caused by a huge surge in flow caused by a big rainstorm, costing between $49 million and $57 million to repair. The incident occurred on February 9 when an equipment failure led to untreated wastewater and stormwater flowing into Puget Sound. The plant was fully repaired and compliant with environmental permits by May 11. The repair costs were expected to be covered by property insurance, with King County responsible for a $250,000 deductible. Insurance was not expected to cover potential regulatory fines or additional environmental monitoring, Failure caused up to $57M in damage to West Point Treatment Plant.
Ok, so what? We the taxpayers have to foot the bill and suffer the ecological consequences.. In addition to the repair costs and increased municipal insurance premiums the City of Portland and King County were fined by the Washington Department of Ecology and the U.S. Environmental Protection Agency (EPA) for sewer overflow violations. These fines were for violations that occurred between July 2020 and June 2021, including several events that led to sewage reaching Puget Sound, Elliott Bay, Lake Union, or the Duwamish River [oai_citation:1,Jan. 11 – Portland and King County fined for sewer overflow violations.
Additionally, there have been lawsuits targeting the EPA for failing to adequately clean up pollution in Puget Sound. These lawsuits, however, are primarily focused on the EPA’s failure to take necessary steps to address nitrogen pollution in the Puget Sound, causing ecological degradation such as reduced oxygen levels and massive algae blooms. These legal actions are generally aimed at enforcing compliance with the Clean Water Act and addressing broader environmental issues in the Puget Sound area.
Most of us in the PNW care about the environment and want to do their part to help. Investing in repairing or installing a new roof water drainage system not only protects your foundation from settling, cracking and flooding. 56,000 gallons of water can move a lot of dirt from under your foundation footing and those repairs can be very expensive. An ounce of prevention is worth a pound of medicine.
Stay dry and call PNW Drain Pros for your roof drainage service.