We haven't been back to Little Canada, to our old neighborhood since
we moved in 2015. Last Monday, after spending a day with friends and
family, we decided to take a "tour" of the place we lived for 18 years;
the longest period of calling a place home in our lives. A lot had
changed, a lot stayed the same, and some of it was unrecognizable. Passing by our lake, via 35E at rush hour was startling. Traffic is almost exponentially greater, noisier, and dirtier. Clearly, either the increased lane-count has attracted commuters who once took a different route or development north of St. Paul is really ramping up. I have no idea when Google took the photo [below], but I can guarantee it was not on a Monday at 3PM.
The biggest reason we bought our home on Lake Shore Avenue was the lake; Savage Lake. We liked the yard and the privacy. I loved the giant garage. Elvy loved the weird layout of the house and the potential of the basement for workspace for her art. We both loved the idea of having a home with a lake in the backyard. I realize that Minnesotans discount bodies of water like Savage Lake as if they are just holes in which to dump sewage, but the rest of the country (especially west) has a different perspective on precious water resources. Not different enough to stop pissing, shitting, and wasting their water, but at least slightly more cognizant than Minnesota where we have so much water we delude ourselves into thinking it is endless. If you look at the past entries in this blog, you'll see that we spent almost as much time in our backyard enjoying our "lake" as we did inside hiding from winter. Before we moved to Little Canada, I had never thrown a party in my life. Because of Savage Lake, we had a wedding reception, annual Little Canada Days fireworks parties, sledding parties, a college graduation bash, and dozens of get-togethers in our backyard that always included some aspect of being on the lake in boats, skis, snowshoes, sleds, or just sandals or winter boots. We hiked the lake in the winter, boated it in the summer, and enjoyed it every day we lived in Little Canada. In the end, it was the thing we both knew we would miss the most about our old home. It still is.
When we lived in the Cities, we regularly compared our industrial noise neighborhood to friends' homes and our daughter's home in Dinkytown. Other essays in this blog talk about the unhealthy expansion of noise in our old backyard and I won't beat that horse more more in this essay, but if you are fooling yourself into believing that you can live with 85dBA-and-above-noise on a constant basis you already need medical assistance. Today, there are four lanes (two in each direction) on 35E that didn't exist when we left the Cities. If traffic expands to fill the available space, as it usually does, that probably means the noise level in my old backyard has risen by 3-8dBASPL.
NOTE: You may not be familiar with the usual verbiage used in discussing noise levels. "dBASPL" means deci (1/10) Bells (a measure of acoustic loudness) A (A-weighted to approximate the sensitivity of human hearing to sound at various loudness levels) and SPL (sound pressure level, a necessary addition because decibels are used for a variety of energy measurements from electrical to light to touch and so on). Forgetting the weighting aspect for a moment, the threshold of human hearing is 0dBSPL and the generally accepted threshold of pain is around 120dBSPL. The aspect of this specification I want to point out here is the A-weighting. Our hearing mechanism is fairly insensitive to low and high frequency sounds at low volume. A-weighting is intended to compensate for human hearing nonlinearity for sounds below 55dB (unweighted). So, anytime you see a specification like "90dBA" you should understand the "A" is being abused for some reason. The reason, in the case of sound barriers, is that low frequencies pass through most of the barriers constructed today as if that barrier is insignificant. So, using A-weighting allows the person doing the testing to discount the irritation factor of loud low frequency sounds artificially. Also, most of the loudest vehicle noises are low frequency sounds. The appropriate weighting system to use at the noise levels presented in the Savage Lake neighborhood would be C-weighting, but that would expose the ineffectiveness of the noise barrier and the health hazard residents are exposed to.
There are lots of technical articles written about noise barriers, but "Building the Wall" probably does as good a job as any at explaining how poorly those structures work for the majority of the neighborhoods they are supposed to help. This classic and simplified description of where that 3dB of noise reduction comes from should be startlingly and discouragingly illustrative of how useless those expensive walls are at any practical distance. Flexible barriers do absorb a little noise energy, but not enough to produce much noise reduction in practical terms. The 6dB justification MNDOT and lobbyists use to justify these installations is purely political and economic. The real argument is "would you rather look at traffic or a wall?" It's not my backyard now, so I can't answer that question. I do know that at least one of our neighbors moved away a year after we left, partially because the noise became intolerable for them.
When we lived in the Cities, we would often visit friends homes or our daughter's home in Minneapolis and enjoy the relative quiet of other parts of the urban environment. Today, even the quietest of those places seems almost intolerably noise to us and, I imagine, our old backyard would be deafening; and I'm not exaggerating. Exposure to noise levels of 85dBSPL and above is a known health hazard. So, while we miss the lake we loved and the neighborhood that was our home, losing almost 30dBCSPL of noise from our backyard was a necessary sacrifice. The reason I decided to add this comment to the long-neglected and nearly-abandoned Savage Lake Blog is that the only reason this human abuse happens is that people believe there is nothing they can do about it. That is not true, but humans/citizens will have to become involved in their local, state, and federal government to fix it. Trump and the Trumpanzees imagine they can turn back the clock to the 1950's and everything will revert to the "good old days." Good luck with that, dummies. Change and the future will happen, regardless of how often Fox News tells you it won't. The country can change for the better or worse, but it will never go back to what we imagined it was 60 years ago.
This blogsite is intended for lakeshore owners in Little Canada, Minnesota who have property on the shores of the much-abused Savage Lake. Your help is needed to protect this historic small lake.
Showing posts with label noise. Show all posts
Showing posts with label noise. Show all posts
Apr 26, 2018
May 17, 2013
MnDOT & Little Canada Sound Barrier Final Proposal
The city's MN Pass Municipal Concent document was delivered to everyone concerned in February. It's worth reading. Apparently, construction on the Mn Pass lane and the rest of the project should begin this summer.
One of the statements in the document that I thought was most "entertaining" was one that stated:

The idea that this giant sand "island" could have come from anything other than MnDOT's crappy drainage design is a huge warning that some monkey business is likely to result from an assortment of bureacrats passing the blame around until the barrier is built and nothing is done about the sediment damage. Any idiot can see the drainage pipe is completely buried and backed up and that the overspill from the ramp is continuing to deposit crap into the lake. Over the years since the last construction, I've watched the characters from the Watershed District paddle out, measure random stuff and paddle back without anything good coming from their "efforst." Even to them, it ought to be obvious where that sediment is coming from. For about a year, there was a plume of crap spreading out from the pipe after every rainstorm. It only took a year for the pipe to clog and the damage to be pretty much complete. However, in the years I've spent fighting for our disregarded and damaged lake I've found that MnDOT and, especially, the DNR hire specially "talented" idiots with no clue, concern, work ethic, or personal honesty. The best we can do is hope for the best, but expect the worst.
Both ends of the lake, northeast and southeast, have been harmed by excessive freeway runoff. The old docks at the southeast end have been hauled out of the water and twisted out of shape by the obscene amounts of sediment runoff. The new Gopher drainage design just dumps Gopher's parking lot crap straight into the lake. At this rate, we can probably expect the lake to fill in a few years and development to being in the resulting mosquito swamp. Sometimes it feels like we're living in Florida (and that is not a compliment).
One of the statements in the document that I thought was most "entertaining" was one that stated:

The idea that this giant sand "island" could have come from anything other than MnDOT's crappy drainage design is a huge warning that some monkey business is likely to result from an assortment of bureacrats passing the blame around until the barrier is built and nothing is done about the sediment damage. Any idiot can see the drainage pipe is completely buried and backed up and that the overspill from the ramp is continuing to deposit crap into the lake. Over the years since the last construction, I've watched the characters from the Watershed District paddle out, measure random stuff and paddle back without anything good coming from their "efforst." Even to them, it ought to be obvious where that sediment is coming from. For about a year, there was a plume of crap spreading out from the pipe after every rainstorm. It only took a year for the pipe to clog and the damage to be pretty much complete. However, in the years I've spent fighting for our disregarded and damaged lake I've found that MnDOT and, especially, the DNR hire specially "talented" idiots with no clue, concern, work ethic, or personal honesty. The best we can do is hope for the best, but expect the worst.
Both ends of the lake, northeast and southeast, have been harmed by excessive freeway runoff. The old docks at the southeast end have been hauled out of the water and twisted out of shape by the obscene amounts of sediment runoff. The new Gopher drainage design just dumps Gopher's parking lot crap straight into the lake. At this rate, we can probably expect the lake to fill in a few years and development to being in the resulting mosquito swamp. Sometimes it feels like we're living in Florida (and that is not a compliment).
Dec 2, 2012
Noise Barrier Modfied
As I wrote a short time back, the commercial interests of Gopher Electronic's owner appears to have some over-riding influence on the barrier construction. The current design, as of November 27, per Jennie Read, PE, North Area Engineer - Ramsey County, (jennifer.read@state.mn.us) is described in the figure below:
I have, as usual, a couple of concerns. It makes sense to begin to taper the wall down as it approaches Little Canada Road. A visual obstruction for vehicles from the west turning south onto the I35E entrance would be a safety hazard. However, terminating the wall at the current location ignores the health and quiet of our neighbors on Australian Avenue. The two issues that will cause their noise levels to be untouched (regardless of the oddly derived MNDOT estimates) are the gap left between the noise source (I35E) and the reflection caused by the earlier east side noise wall. The photo below illustrates that the east wall is nicely lined up to reflect noise from that side of the freeway into the neighborhood directly across the intersection.
Simply extending the wall to match the new east side barrier is not enough to correct the damage done by the original (and poorly considered) noise barrier design. While it might be inconvenient for the business owners to have to install higher signage to be visible to the tiny fraction of drivers who will be looking for signs while negotiating a hazardous section of freeway, the cost to the homeowners should come first for both MNDOT and the City of Little Canada's local government.
Having seen the original noise level estimates made by MNDOT which were used to justify why noise barriers were not recommended when the freeway was expanded, I'm unimpressed by the random numbers their "engineers" have applied to expectations of noise reductions in the neighborhoods. The closer the properties are to the noise barrier, the more effective the barrier will be. Even MNDOT "experts" should know this fact.
Honestly, the more I see these characters abuse science, the more I am convinced of Thomas Huxley's condemnation of the three classes of witnesses, "liars, damned liars, and experts." At least with these new estimates in hand, I will have data to work with in collecting measurements over the next few seasons before the wall is constructed. After the wall is built, it will be interesting to hear the MNDOT excuses for why their numbers, again, failed to approach reality. Before the previous I35E expansion and noise wall construction, the MNDOT optimistic guesses regarding the effects on our property defied logic and science and were, as expected, wrong. Instead of "less than 3dB" of change in the abusive noise levels on our properties, the new traffic expansion increased levels by 5-9dBA and 8-14dBC.
The Little Canada residents living along the south end of the existing west side wall (1o-3o on the MNDOT map above) have voted against the extension of the wall. I suspect it is because they are receiving as much benefit from the existing trees as they expect from a new wall. Due to medical issues, I was not able to attend the November 28 City Council meeting where they expressed their opinions. However, it will be critical for the city and residents to carefully monitor any MNDOT "enhancements" to the existing tree protection, if that becomes part of the plan. When MNDOT planted 4' trees on the west side (near the 1n location on the MNDOT map above), the state's employees cut down several existing 20' trees to "make room" for the new starter plants. Obviously, that was counter-productive and should not be repeated.
I have, as usual, a couple of concerns. It makes sense to begin to taper the wall down as it approaches Little Canada Road. A visual obstruction for vehicles from the west turning south onto the I35E entrance would be a safety hazard. However, terminating the wall at the current location ignores the health and quiet of our neighbors on Australian Avenue. The two issues that will cause their noise levels to be untouched (regardless of the oddly derived MNDOT estimates) are the gap left between the noise source (I35E) and the reflection caused by the earlier east side noise wall. The photo below illustrates that the east wall is nicely lined up to reflect noise from that side of the freeway into the neighborhood directly across the intersection.
Simply extending the wall to match the new east side barrier is not enough to correct the damage done by the original (and poorly considered) noise barrier design. While it might be inconvenient for the business owners to have to install higher signage to be visible to the tiny fraction of drivers who will be looking for signs while negotiating a hazardous section of freeway, the cost to the homeowners should come first for both MNDOT and the City of Little Canada's local government.
Having seen the original noise level estimates made by MNDOT which were used to justify why noise barriers were not recommended when the freeway was expanded, I'm unimpressed by the random numbers their "engineers" have applied to expectations of noise reductions in the neighborhoods. The closer the properties are to the noise barrier, the more effective the barrier will be. Even MNDOT "experts" should know this fact.
Honestly, the more I see these characters abuse science, the more I am convinced of Thomas Huxley's condemnation of the three classes of witnesses, "liars, damned liars, and experts." At least with these new estimates in hand, I will have data to work with in collecting measurements over the next few seasons before the wall is constructed. After the wall is built, it will be interesting to hear the MNDOT excuses for why their numbers, again, failed to approach reality. Before the previous I35E expansion and noise wall construction, the MNDOT optimistic guesses regarding the effects on our property defied logic and science and were, as expected, wrong. Instead of "less than 3dB" of change in the abusive noise levels on our properties, the new traffic expansion increased levels by 5-9dBA and 8-14dBC.
The Little Canada residents living along the south end of the existing west side wall (1o-3o on the MNDOT map above) have voted against the extension of the wall. I suspect it is because they are receiving as much benefit from the existing trees as they expect from a new wall. Due to medical issues, I was not able to attend the November 28 City Council meeting where they expressed their opinions. However, it will be critical for the city and residents to carefully monitor any MNDOT "enhancements" to the existing tree protection, if that becomes part of the plan. When MNDOT planted 4' trees on the west side (near the 1n location on the MNDOT map above), the state's employees cut down several existing 20' trees to "make room" for the new starter plants. Obviously, that was counter-productive and should not be repeated.
Labels:
barrier,
i35e,
landscaping,
mndot,
mnpass express lane,
noise,
property taxes,
sound
Nov 5, 2012
Variations on the Noise Wall
Apparently, the Little Canada City Council is doing an end run around the will of the property owners on Australia Avenue. The owner of Gopher Electronics convinced the council that his property will somehow be damaged if there isn't a line-of-sight from the freeway to his building and that his tiny building provides ample noise protection for the people who live on the streets "blocked" by his building. So, the council is looking at (or has already decided on) shrinking the length of the northwest side of the proposed noise wall for his benefit.
Obviously, this completely eliminates the value of the noise wall for 2/3 of the residents on the west side of the freeway. As the DOT's own literature states, effective noise barriers must:
Reducing the length of the barrier will effect the efficiency of the barrier for far more than just the citizens "protected" by the Gopher building. It will eliminate much of the barrier's effect for most of us on the west side.Since Gopher Electronics has been accused of being the cause of a lot of the lake's degradation over the years, it is hard to see why the city would be suddenly concerned about that business' input regarding the neighborhood.
There is still some time for public input before this project is turned over to the bureaucracy. "The Administrator reported that MN DOT is requesting that the City hold a public hearing on the MN PASS project, and staff is recommending the hearing be held on Wednesday, November 28th at 7:30 p.m. The Administrator pointed out that last evening MN DOT held an open house on the project at City Hall. The issue of sound walls was discussed with residents, and there are some areas abutting the project where property owners favor additional sound walls and some not. The Administrator noted that the Heather Oaks property owners abutting the project do not support the addition of a sound wall, but would like to have additional landscaping installed." Stay tuned, this "discussion" isn't over yet.
The fact that none of the council members or the mayor are opposed in the upcoming election is probably bad news for the city. It says we're either completely satisfied with city government, we're completely apathetic about our homes and community, or we're afraid to raise out heads up because they might get shot off.
Obviously, this completely eliminates the value of the noise wall for 2/3 of the residents on the west side of the freeway. As the DOT's own literature states, effective noise barriers must:
- must be tall and long with no openings;
- are most effective within 61 meters (200 feet) of a highway (usually the first row of homes);
- a barrier should be at least eight times as long as the distance from the home or receiver to the barrier;
Reducing the length of the barrier will effect the efficiency of the barrier for far more than just the citizens "protected" by the Gopher building. It will eliminate much of the barrier's effect for most of us on the west side.Since Gopher Electronics has been accused of being the cause of a lot of the lake's degradation over the years, it is hard to see why the city would be suddenly concerned about that business' input regarding the neighborhood.
There is still some time for public input before this project is turned over to the bureaucracy. "The Administrator reported that MN DOT is requesting that the City hold a public hearing on the MN PASS project, and staff is recommending the hearing be held on Wednesday, November 28th at 7:30 p.m. The Administrator pointed out that last evening MN DOT held an open house on the project at City Hall. The issue of sound walls was discussed with residents, and there are some areas abutting the project where property owners favor additional sound walls and some not. The Administrator noted that the Heather Oaks property owners abutting the project do not support the addition of a sound wall, but would like to have additional landscaping installed." Stay tuned, this "discussion" isn't over yet.
The fact that none of the council members or the mayor are opposed in the upcoming election is probably bad news for the city. It says we're either completely satisfied with city government, we're completely apathetic about our homes and community, or we're afraid to raise out heads up because they might get shot off.
Oct 14, 2012
I-35E MnPASS Noise Wall
This is a copy of the letter I sent regarding the noise wall plan and the meeting the city will be having regarding this proposal on October 23 at the Little Canada City Center:
From: T.W. Day [mailto:twday60@comcast.net]
Sent: Sunday, October 14, 2012 12:39 PM
To: 'kevin.walker@state.mn.us'
Cc: joel.hanson@ci.little-canada.mn.us'
Subject: Little Canada I-35E MnPass Noise Wall
I am a property owner on the west side of Savage Lake, directly across from I35E and north of where the noise barrier on the east side ends.
---------------
Thomas Day
2660 Lakeshore Avenue
Little Canada, MN 55117-1320
twday60@comcast.net
651/415-2992
I want the noise barrier.
Comments:
The noise barrier will, as I suspect the state knows, will be of limited value in regard to the unhealthy noise levels the freeway expansion has created for our property. When the freeway was expanded and the barrier installed on the east side of the freeway, the noise level in our backyard and inside our home rose significantly (approximately 5-10dB, depending on the time of year and day). The state's "acoustician" made some wild and unsubstantiated claims that we would not see more than 3dB of noise increase after the freeway redesign and none of those assumptions made much sense, even based on the information that you'd hope anyone involved in freeway design would have available (http://www.fhwa.dot.gov/environment/noise/noise_barriers/design_construction/keepdown.cfm).
I have measured the noise level in my backyard at various times of the day, week, year, and since we moved here in 1997 and found that the noise levels have regularly exceeded OSHA safety guidelines for industrial work spaces. Before the freeway expansion and construction of the east side noise wall, my spring measurements (typically worst case in my measurements) were around 80dBA and 86dB unweighted. After the freeway expansion those measurements increased to 87dBA and 93dB unweighted. Doing an extended noise study during those worst case periods found peaks of 98dBA from the middle of our back yard.
Even more disturbing is the fact that the general noise from the freeway was more-or-less unfocused before the east side noise barrier. After that barrier was constructed, the noise levels clearly increased as vehicles approach and pass that reflection source. The fact that noise generators can easily be localized when the are near the barrier proves that the reflection from the east side barrier has increased the noise level on our property. Something the previous "engineer" claimed would not happen and something that any competent acoustician would expect to be a problem.
For people who live within the first 100 feet of the barrier, I would expect a dramatic improvement in noise levels after the proposed barrier is constructed. For those of us who live considerably further from the freeway, I doubt that we'll see significant improvement. An improvement on this plan would be to add absorption to the barrier design. The easiest and cheapest way to do that would be to include a budget for enough evergreen trees to provide year-around full coverage of the noise-generating area. That was part of an earlier noise abatement plan and should be included in this plan. Even if the trees do not provide much effect early on, the larger they grow the more effective they will become and they will not require maintenance if they are planted on the lake-side of the barrier. This can only be good visually and sonically for the embattled residents around our lake.
From: T.W. Day [mailto:twday60@comcast.net]
Sent: Sunday, October 14, 2012 12:39 PM
To: 'kevin.walker@state.mn.us'
Cc: joel.hanson@ci.little-canada.mn.us'
Subject: Little Canada I-35E MnPass Noise Wall
I am a property owner on the west side of Savage Lake, directly across from I35E and north of where the noise barrier on the east side ends.
---------------
Thomas Day
2660 Lakeshore Avenue
Little Canada, MN 55117-1320
twday60@comcast.net
651/415-2992
I want the noise barrier.
Comments:
The noise barrier will, as I suspect the state knows, will be of limited value in regard to the unhealthy noise levels the freeway expansion has created for our property. When the freeway was expanded and the barrier installed on the east side of the freeway, the noise level in our backyard and inside our home rose significantly (approximately 5-10dB, depending on the time of year and day). The state's "acoustician" made some wild and unsubstantiated claims that we would not see more than 3dB of noise increase after the freeway redesign and none of those assumptions made much sense, even based on the information that you'd hope anyone involved in freeway design would have available (http://www.fhwa.dot.gov/environment/noise/noise_barriers/design_construction/keepdown.cfm).
I have measured the noise level in my backyard at various times of the day, week, year, and since we moved here in 1997 and found that the noise levels have regularly exceeded OSHA safety guidelines for industrial work spaces. Before the freeway expansion and construction of the east side noise wall, my spring measurements (typically worst case in my measurements) were around 80dBA and 86dB unweighted. After the freeway expansion those measurements increased to 87dBA and 93dB unweighted. Doing an extended noise study during those worst case periods found peaks of 98dBA from the middle of our back yard.
Even more disturbing is the fact that the general noise from the freeway was more-or-less unfocused before the east side noise barrier. After that barrier was constructed, the noise levels clearly increased as vehicles approach and pass that reflection source. The fact that noise generators can easily be localized when the are near the barrier proves that the reflection from the east side barrier has increased the noise level on our property. Something the previous "engineer" claimed would not happen and something that any competent acoustician would expect to be a problem.
For people who live within the first 100 feet of the barrier, I would expect a dramatic improvement in noise levels after the proposed barrier is constructed. For those of us who live considerably further from the freeway, I doubt that we'll see significant improvement. An improvement on this plan would be to add absorption to the barrier design. The easiest and cheapest way to do that would be to include a budget for enough evergreen trees to provide year-around full coverage of the noise-generating area. That was part of an earlier noise abatement plan and should be included in this plan. Even if the trees do not provide much effect early on, the larger they grow the more effective they will become and they will not require maintenance if they are planted on the lake-side of the barrier. This can only be good visually and sonically for the embattled residents around our lake.
Labels:
freeway,
little canada,
mnpass express lane,
noise,
savage lake
Jan 31, 2011
"Unweave the Weave" Landscaping
The February-March edition of the Little Canada Le Petit Canadien mentioned that about $250,000 will be made available for landscaping to recover some of the damage done by the increased width of the freeway and to moderate some of the noise that came with that freeway traffic. All I can say is, "it's about time." I've monitored the sound pressure level in my backyard during rush hour and the noise level far exceeds EPA and OSHA safe limits; well into the low 90dBSPL territory.
The Canadien article suggested that the City Council has "focused on the area between I-35E and West Savage Lake in an attempt to create some natural barriers to the sound and view coming from the freeway." This is a solid approach. The extended barriers on the east side of the lake have reflected additional noise in our direction, which makes safely enjoying our neighborhood and yards impossible during much of the day. Hopefully, the character MnDOT used as an "acoustic expert" won't be involved in this analysis, since pretty much all of his guess-timates about the effects on our neighborhood from the freeway expansion and the noise barriers were so far off I'd be surprised if that guy ever attended a science class at any time in his life.
Sound absorption is a much better tactic for silencing noise than obstruction. The noise barriers have a limited effectiveness, based on height, length of the barrier, distance from the noise source and the target clients, the noise bandwidth, and the mass of the materials used for the barrier. Absorption actually converts sound energy to heat; not a lot of heat, but that energy is no longer sound. Noise doesn't bounce off of conifers. Instead, the air motion pass through the branches and leaf tissue and moving those obstacles converts sound to motion and heat.

Of course, the trees will absorb some of the carbon dioxide, lowering pollution levels. In all, this is a plan my wife and I have been advocating for almost a decade and I'm glad to see the city and state buying into it. We should all give Joel Hanson a call at 651/766-4040 or email at joel.hanson@ci.little-canada.mn.us and get the city behind this idea. With decent sized plantings, almost immediately we could have a substantially more quiet neighborhood. In a few years, this could be our view of the freeway.
The Canadien article suggested that the City Council has "focused on the area between I-35E and West Savage Lake in an attempt to create some natural barriers to the sound and view coming from the freeway." This is a solid approach. The extended barriers on the east side of the lake have reflected additional noise in our direction, which makes safely enjoying our neighborhood and yards impossible during much of the day. Hopefully, the character MnDOT used as an "acoustic expert" won't be involved in this analysis, since pretty much all of his guess-timates about the effects on our neighborhood from the freeway expansion and the noise barriers were so far off I'd be surprised if that guy ever attended a science class at any time in his life.
Sound absorption is a much better tactic for silencing noise than obstruction. The noise barriers have a limited effectiveness, based on height, length of the barrier, distance from the noise source and the target clients, the noise bandwidth, and the mass of the materials used for the barrier. Absorption actually converts sound energy to heat; not a lot of heat, but that energy is no longer sound. Noise doesn't bounce off of conifers. Instead, the air motion pass through the branches and leaf tissue and moving those obstacles converts sound to motion and heat.

Of course, the trees will absorb some of the carbon dioxide, lowering pollution levels. In all, this is a plan my wife and I have been advocating for almost a decade and I'm glad to see the city and state buying into it. We should all give Joel Hanson a call at 651/766-4040 or email at joel.hanson@ci.little-canada.mn.us and get the city behind this idea. With decent sized plantings, almost immediately we could have a substantially more quiet neighborhood. In a few years, this could be our view of the freeway.
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