Dear Redmond City Council Members-
I believe that our community should switch all distribution power lines in local neighborhoods from power poles which are above ground to underground power lines due to the weather and vegetation in our area. We experience frequent power outages in the winters because of the strong wind storms that knock over trees causing poles to be severely damaged or to fall.
I learned that the power grid supplies electricity to our community using six parts: power generating plants, step-up substation transformers, (long distance) transmission lines, step-down neighborhood substation transformers, distribution lines (often on power poles) and transformers. Power plants generate electricity that goes first to a substation transformer that ups the voltage and sends the power to the heavy-duty transmission lines. Then, when the power reaches neighborhoods, it’s sent through a neighborhood substation transformer that steps down the voltage and send it to the smaller distribution lines that carry the electricity shorter distances within an area. Transformers in metal boxes then step down the electricity a little more before it enters our houses.
I drove around our neighborhoods and saw two different ways that power lines are built in Redmond: above ground (on poles) and underground (in concrete tubes called conduits). I couldn’t see the actual underground lines, but I watched a video of one being installed into a square concrete conduit.
Both systems have pros and cons. Above ground power poles are easier and faster to fix because they are easier to get to and it’s easier to find the broken areas. However, they are more likely to need fixes because they can be blown over in storms or hit by falling trees which leads to more frequent power outages. These lines can also be very dangerous to people and property. They can fall on cars and houses causing serious damage and could result in deaths or injuries. These lines can also spark and cause fires when they fall.
Underground lines are much harder to repair because you must dig to find the problem. Repairs take longer and underground lines need to be replaced more often. Also, underground lines are not a good idea in areas prone to flooding, but thankfully we do not live in one of those areas. However, there are lots of advantages to underground distribution lines. They are never blown over by wind, trees or branches can’t hit them or knock them down and they can’t cause fires as easily. In Redmond, we have many, many large trees near power lines. We also have many wind storms each year and some ice problems. All of these things damage our above-ground power lines each year, but our underground lines are safer during our storm season.
The major disadvantage of underground lines is how expensive they are, costing 4 to 14 times more to install per mile than above ground cables according to the May 2011 paper "Underground Electric Transmission Lines" published by the Public Service Commission of Wisconsin. However, because our main problem in Western Washington with losing power is due to wind storms, above ground power lines are a bigger hazard for us than they are in other places. I believe the City of Redmond should work with citizens, the State government and engineers to find ways to keep the cost of installing and repairing underground lines low enough to afford. They could look for less expensive materials, try to put lines underground when they are already digging in a neighborhood for a different reason such as replacing roads or sidewalks, ask businesses and residents who are affected by the frequent power outages to donate to the City’s underground power efforts and ask the State government to help all of Western Washington budget for “undergrounding” power lines. They could also research ways to install doors or access points to make it easier to get inside conduits when repairs are needed and a computer system that can locate broken areas in the lines ,so workers don’t have dig in several places where it may not be necessary.
Sincerely,
BKP
References:
- "Underground Electric Transmission Lines" published by the Public Service Commission of Wisconsin, May 2005
- http://ca.audubon.org/conservation/energy-storage-and-electricity-grid
- http://www.elp.com/articles/powergrid_international/print/volume-18/issue- 2/features/underground-vs-overhead-power-line-installation-cost-comparison-.html
- https://wildfiremitigation.tees.tamus.edu/faqs/how-power-lines-cause-wildfires
- https://www.cnn.com/2017/09/14/us/underground-power-lines-trnd/index.html