Commentary: Is Air Quality the Only Issue the Opposition Has on Nishi?

In 2016, I fully expected that Nishi would prevail and become the first successful Measure R project.  It was close.  How close?  The early returns showed Nishi passing, but as the night wore on and the core areas of town came in, it fell between 600 and 700 votes short.

Our analysis showed there were two key factors in its demise.  The first was the issue of traffic impacts on Richards Boulevard.  The second and perhaps more surprising issue was the affordable housing issue, but it was pivotal because a lot of students, who ordinarily would have supported a housing project, opposed Nishi on the grounds that it lacked sufficient affordable housing.

Clearly the developers took those mistakes to heart in developing the current proposal.  They have made it student housing only – eliminating the for-sale component as well as the commercial component.  That allows them to develop it with UC access only, eliminating the issue of traffic impacts while mitigating a third issue – air quality.

If my read is right at this point in time, while there are a number of smaller objections, it looks like the major battle over Nishi is going to hinge on air quality.

Can the project be defeated only on those lines?  Hard to say.  If it comes down to simply longtime Davis residents, then it is hard to know.  If a large and organized group of students show up to vote, the issue may not matter at all.

Clearly this is an issue that the developer team will have to get in front of – they were slow in responding to some of the issue threats in 2016, to their detriment.

This letter from Al Sokolow in the local paper exemplifies the risk.

Professor Sokolow writes: “Until now, I had not paid much attention to the proposal for student residential development on the Nishi property wedged between the UC Davis campus and Interstate 80. And to the extent that I did read and think about the proposal, I mildly viewed it as a good project — one that would help cure the community’s housing shortage in a desirable location close to the campus.”

He continues: “Reading Tom Cahill’s excellent commentary in The Enterprise, however, has sharply changed my view. His is no simplistic NIMBY argument from antagonistic neighbors. Rather, Cahill gives us a convincing, science-based picture of the health risks endemic to the site next to the interstate highway and the mainline of the Union Pacific.

All of that heavy truck and auto traffic and diesel-powered train movement, compounded by braking and acceleration, creates dangerous air quality conditions for human habitation,” he concludes.  “Cahill is an eminent physicist who has made an internationally respected career of researching air-quality issues. His concerns about the Nishi property deserve our close attention.

I have actually spent a lot of time in the past few months reading through Dr. Cahill’s research and opinions on this matter.  What I have concluded is that Dr. Cahill’s risk assessment is on the extreme side.  He believes even with a tiny amount of risk, we should forgo the project.

The problem I have with that is that I think he is focused strictly on the risks of exposure to air quality rather than the totality of the circumstances.  That totality includes the fact that if students do not live at Nishi, they have to live somewhere else.  That means that other locations also have air quality concerns.  Moreover, other locations require driving and other risks.

As Richard McCann points out, “Cahill is ignoring all of the other mortality risks he creates in his personal day to day life.”

A key point that I think hasn’t gotten near enough attention is whether the mortality risks are higher from a limited period of exposure to particulate matter at Nishi over a period of one to three years, or from the additional driving to and from campus and exposure to the risks of automobile accident and additional added pollution.

The question I keep asking – to which there has been no satisfactory answer regarding the limited duration of residencies at Nishi – is what level would have to be present in order to create a problem?  As I pointed out on Sunday, that would seem a fundamental question since the data we do have doesn’t seem to suggest that Nishi poses an enormous health risk.

I also think that at the Planning Commission, the developer team did a good job of addressing some of these concerns through the work of Dr. Charles Salocks, Don Shor and Larry Greene.

There are several key points that need to be made in response to letters like that from Dr. Sokolow.

First, as Dr. Salocks points out: “The health assessment in the EIR is based on an assumption of a residency of 70 years with no mitigations. (The) typical residency at Nishi will be 1-3 years, not 70. This alone reduces long-term health risk by at least 95%.”

That again gets to my question which Dr. Cahill has not answered, despite my repeated asking.

Second, Don Shor in his presentation found that the urban trees play a huge role in reducing pollution and improving air quality, by as much as 16 percent.  And we know that Dr. Cahill a decade ago did a vegetation study that found that they could reduce diesel/smoking car exhaust by 70 percent with the proper vegetation.

We also know that the air filtration system can reduce indoor air by up to 95 percent per the EIR.

Add to that, data on the wind directions suggest that the worst case scenario only happens five percent of the time – we have ten-year wind studies that won’t be impacted by more on-site study.

Add all that up and you have greatly reduced both the indoor air, which Dr. Cahill a decade ago said “drives the bad news for residences” given the 24-hour-a-day factor, and the outdoor air.

Is that enough?  Apparently not for Dr. Cahill who argues, “Even one preventable death is not acceptable.”

I think people who follow Dr. Cahill’s advice need to understand where he is driving with this.  His allowable risk level is therefore not merely very low, but zero.   Given what we know about risks in the real world, that doesn’t seem very reasonable after all.

My view is that I can’t tell people which level of risk to assess.  Rather I would prefer to simply be able to explain to the voting public where Dr. Cahill comes down and allow the voters to make their own determination.

—David M. Greenwald reporting

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About The Author

David Greenwald is the founder, editor, and executive director of the Davis Vanguard. He founded the Vanguard in 2006. David Greenwald moved to Davis in 1996 to attend Graduate School at UC Davis in Political Science. He lives in South Davis with his wife Cecilia Escamilla Greenwald and three children.

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  1. Todd Edelman

    In regards to

    We also know that the air filtration system can reduce indoor air [pollution] by up to 95% per the EIR.

    Can you please direct me to the part of the EIR where this is stated? But “pollution” in this context – in this conversation – is simply too imprecise. Do you mean bad ideas, badly aimed urine, teeny tiny particles? PM 2.5 and below?

    Furthermore, that 95% is not possible, even with closed windows, few people entering and exiting, etc. It seems to be referring to a MERV 16 filter and what can pass through it, rather than the quality of the air in the room after some point in time. But MERV 16 is basically a HEPA filter – a very expensive one, too – which requires huge amounts of energy to push air though it. (Lincoln40 is supposed to have MERV 13 filters. I have no idea what’s installed – if anything better than run-of-the-mill MERV 8- in the apartments on the south side of East Olive, New Harmony, Motel 6 off Mace (LOL), Merryhill Preschool (which seems to be about 600 ft. south of the freeway)… how many years does the average person work at Dutch Bros.?

    I really don’t understand why you constantly repeat the 5% worst-case thing, and neglect to mention that at least half of the time the wind blows north from – okay – less filthy sections of the freeway. And as I mentioned last week, how does wind direction correlate with the times that traffic is congested? (Why this was left out of the presentation of this information is sort of bizarre in retrospect…)

    All of this not very precise information pollutes the good points made about the disadvantages of students coming from greater distances and some other things.

    Also, “accident”, seriously?

    Yes, let’s be serious: We need to move everything not sealed inside over-pressurized non-residential buildings to over 500 ft from the I-80 through its entire sordid passage through our progressive city. And then everything between 500 and 1000 ft. needs the highest filtration possible, both inside (filters on forced air systems) and outside (lots of sticky trees, that grow very fast! Hey, how long before the trees planned for Nishi 2.0 reach predicted efficacy? Ten years?)

    In the meantime let’s get lots of money by implementing a toll and otherwise making the Federal govt. and Caltrans support the construction of some kind of roof over the I-80 which can do the best job in blocking sound and filtering air. Combined with high tech asphalt to cut down vibration… I am not sure what’s best:  Some kind of open greenhouse with sticky, particle-assassin plants inside, soft surfaces to absorb sound… and solar panels along the south face of the entire structure may provide Davis with up to 1/5 of its current electricity needs.

    The only problem with this scenario is that it will make Davis so famous that every day about ten international news organizations will be meeting with the City Council and volunteer Commission members, taking up all their time, and all the hotel beds.

    Grow up, people. Attack and defeat the I-80. Warm up to that by burning to ash the archaic, anachronistic and anti-egalitarian quaint and useless-as-marketing pennyfarthing/highwheeler symbol.

    1. David Greenwald

      From the EIR: “Mitigation Measure 4.3-5c: The air filtration systems on all residential buildings and buildings in which people work shall achieve a minimal removal efficiency of 95 percent for UFP…”

  2. Don Shor

    The presentation by Dr. Salocks dealt with the health risk issues. The presentation by Larry F. Greene dealt with the air quality factors. The following were some of the points I made.

    Examples of benefits of urban trees in general:

    The presence of trees in urban areas is calculated to reduce pollution and improve air quality by as much as 16%.

    A field study in Sydney Australia showed a 42% reduction in particulate matter from sites with more trees.

    Vegetation planted specifically for screening air particles:

    Trees planted outside the home can provide substantial reductions in PM inside the home (>50% reduction).

    Cahill (2008) found that redwood vegetation removed 79% of 0.17μm diameter particulate matter in a wind tunnel experiment.

    Further wind tunnel research used by Dr. Cahill estimated very high filtration of very fine particles by two species of conifers (redwood and deodar cedar), from 79 – 99%.

    Research at Willett Elementary School demonstrated the efficacy of specific types of trees based on their foliage.

    The EPA has recognized vegetative buffers among their recommended air mitigation strategies and has guidelines for implementation. As of April 2017 the state Air Resources Board also now includes vegetative buffers among their recommended strategies that reduce traffic emissions.

    Species selected for particular leaf morphology, planted in higher density than usual, with a balance of species chosen for fast growth, longevity, and diversity, can make an effective barrier providing significant mitigation of fine particle pollution.

    The project will have a 100’ deep urban forest with multiple layers of foliage. This is significantly wider than the typical vegetation buffer. There would be more than 2000 trees and shrubs planted on relatively high densities in the Nishi Urban Forest.

    The tree canopy planned for the parking lot will provide an additional layer of filtration, as will the landscape plantings around the residences. Augmenting the existing trees in the CalTrans easement, where there are mature oaks, would provide yet another layer of vegetation. All told, air would pass through five zones of vegetation before reaching the buildings.

    The Planning Commission presentation is here:

    Nishi begins at about 1:48. Air quality discussion begins at about 2:14.

  3. Howard P

    Interesting term in the title, and much of the discussion to date:  “the Opposition”, and “the Proponents”… several ‘flavors’ of which folk have opined on each.  Everything from build everything to build nothing.  Some have legitimate concerns where they are leaning for, or leaning against.  There appears to be also an outlier who would like to see I-80 truncated at one end in West Sac, the other end in Dixon, unless a significant portion is hermetically sealed.

    At this point, I neither support nor oppose the project.  I have a problem with the term Nishi 2.0.  It is actually Nishi 3.0.  But will cave to the majority, and will refer to what I know as the original Nishi proposal (’90’s) as Nishi -1.0.

    Not actively, but I believed Nishi -1.0 was an “abortion”… had Measure R been in place I would have voted against it… Nishi 1.0, same, but I did vote against it… Nishi 2.0 is likely (slightly greater than 50% chance) to go to Nishi 2.1 before a vote.

    Nishi 2.0 is far superior the the earlier ‘releases’ in my mind. But still, I have reservations… the main one being “is it real”?  UPRR is unlikely to be a problem… they can eliminate the at-grade crossing to Nishi @ Arboretum Drive.  Main concern is no concrete evidence that UC/UCD are “on-board” with the motor vehicle connection to campus… if I had that, I’d definitely vote in favor of the project… as it stands, don’t know how I would vote in June…

    1. David Greenwald

      Let’s say that UCD is not on board (which doesn’t make a lot of sense since they know there needs to be more student housing), if the project gets approved by the voters and there is no vehicle access, then the project cannot proceed.  So why should that be a barrier to approving the project?

        1. Howard P

          My point is why have we heard little/nothing from UC/UCD about the access?

          Guess I’ll be a No vote and will encourage others to do the same.

          In the meantime, will encourage the CC not to move forward with a Measure R vote.

          OK… not moving forward makes any air quality issues moot, supports the no growth agenda, and leaves us where we are on rental vacancies.  Fine.  I’ve got mine.

          And its value will just go up given the market.

          And for so long you were accused by some of being pro-growth…

    2. Richard C

      …UPRR is unlikely to be a problem… they can eliminate the at-grade crossing to Nishi @ Arboretum Drive.  Main concern is no concrete evidence that UC/UCD are “on-board” with the motor vehicle connection to campus… 

      Do we have any data on how much the under crossing would cost and how long it would take to build?

      1. Todd Edelman

        If I recall correctly at the BTSSC meeting in December, the developer would pay for it. They also promised to build it first… and that makes sense as it’s the best egress for construction purposes. If it’s built first it may also be a bus route even before the rest of the project is well under way, though this might not work during construction.

        I see 0% chance of UCD not agreeing to all of this. IF the project is built any parking present should count as one-space-that’s-it campus parking. UCD should push for that, too.

        1. Howard P

          Todd… we already have a bike ped connection to UCD, at Nishi… go for it!  No cars, no motor vehicles (except maybe EV’s) allowed!  Anywhere on Nishi…

          Can’t see the backup for your ‘vision’, specifically,

          I see 0% chance of UCD not agreeing to all of this.

          Sure thing?  Please share your reasons/cites for such a ‘vision’… am skeptical…

          Can’t think of a single thing that I am 100% sure of, including the sun ‘rising’ tomorrow… might go super nova or collapse tonight…

          UCD is less stable than the sun…

        2. Todd Edelman

          Perhaps we’re not talking about the same thing here BUT the undercrossing features prominently in visualizations – that’s all I am talking about.

          I DO think that the walk and bike undercrossing should be as separated from the motor part as possible. And also very wide for both. Hopefully this can all count as “one” crossing from the perspective of Union Pacific.

        3. Howard P

          Todd… you still only on picture books?  Where is the “text”? [Actually, UCD commitment for context]

          I can draw a picture of how lead can be turned to gold… doesn’t mean it’s real…

          UPRR is solvable… UC/UCD cooperation, not so much, and I say this having been in meetings with the developer, City and UCD… open, but not committed…

      2. Ken A

        It depends if we have the private sector or the public sector build it…

        In the 1930’s it took American Bridge and Iron three years and $77 million to build the entire San Francisco Bay Bridge (and drill a tunnel through an island).

        After the 1989 Earthquake it took the private sector and politically connected private contractors twenty four (24) years and $6.4 BILLION to build half a bridge (and they didn’t even have to drill a hole in an island)…


        1. Ron

          I included the link because I was curious how many people died, building the original span.  But now that I’m looking at it more closely, there’s also this (regarding the replaced section):

          “Construction officially began in 2002, and nearly 8000 workers built a Skyway viaduct, self-anchored suspension bridge, S-curve, and 526-foot tower that will allow the bridge to withstand a Maximum Creditable Earthquake (MCE) of 8.5 magnitude.”

          I won’t note anything else regarding the bridge replacement, since this is getting off-topic. However, I didn’t realize that the new span is (supposedly) so “earthquake-resistant”. I wonder if there will be a “test”, within most of our lifetimes? Dare we say “earthquake-proof”? “Unsinkable”?


      3. Howard P

        Back of envelope estimate… based on the existing bike/ped crossing… $10 million… for design, permits etc. (project would require a separate EIR[?]), 3 years… for construction, 1.5 years.  My best guess, based on experience… actual results may vary, but I was being optimistic…

        I assumed UCD was a full “partner”… and no opposition from community/activists…

      4. Richard C

        Back of envelope estimate… based on the existing bike/ped crossing… $10 million… 

        I’m not an expert on construction costs, but my guess is that it would be significantly more than $10 million. Probably more like 3 to 4 times that much.  It would require building a temporary “shoefly” track around the building site to reroute train traffic during construction. Since this is a mainline railroad this shoefly would need to be very substantial and would be very costly.

        1. Howard P

          OOPS!  Forgot about the shoofly!  You’re right… my bad…

          Also, forgot the additional height of the structure if double-deckers are accommodated, as some have suggested.  That increases the length of the ramps needed on both sides…

          Just throw my envelope into recycling… the shoofly itself isn’t that bad… but there are other elements I had missed.

  4. Richard McCann

    Todd Edleman writes ” Attack and defeat the I-80.” That’s tilting at windmills. The City has absolutely no control over that issue, and trying anything will be equivalent to saying “we’ll hold our breath until you act”. This point is simply a distraction.

    1. Todd Edelman

      To very nearly quote Guinan in her words to Commander / Acting Captain Riker on a less than optimistic eve before a confrontation with the Borg:  “If you think you’re going to lose, you’ll probably find a way to make it happen.”

      Seriously, dude: Courageous politicians and clever lawyers with the selfless support of citizens have pushed forward many a thing in this country. I’m clearly patronizing you with this comment, so please tell me what I’m missing.

      Imagine if all we had was the Lincoln Highway and an underfunded passenger railway abused by a freight monopoly and the Federal government and Caltrans wanted to build Megahighway 3.0 and their argument to allow it was: “Davis is a university town, most people living near the highway will only be exposed to it for a couple of years.” They might even offer to build / adapt current buildings for student housing and plant lots of lush, sticky trees within the 500 ft. corridor on either side of the highway.

      Would we support this?

      1. Ken A

        I’m wondering if Todd has asked West Sac and Dixon if they will support the giant fans that will blow pollution from his Davis I80 tunnel in to their cities?

        1. Todd Edelman


          ‘toxic waste’

          Indeed. What happens to these particles after they are seized from the air by the floral assassins that feature so prominently in Don’s shoring up of defenses against UFPs? I assume that they make their way to ground at latest in the winter, and then affect the soil in ways inert to its opposite? Do they become friable again? What happens when there’s a – not so rare in these parts – somewhat exceptional wind event? Do the Holy Adhesivassins* play a tug-of-war with their archfoe, the Winds of Dispersal?

          * portmanteau of “adhesive” and “assassins”.

          1. Don Shor

            .Indeed. What happens to these particles after they are seized from the air by the floral assassins that feature so prominently in Don’s shoring up of defenses against UFPs?

            Short answer: they are metabolized, sequestered, or just remain inert. Answer depends on what they are and what form they’re in.

  5. Dave Hart

    David, you keep asking unsuccessfully for data from Dr. Cahill and I keep asking similar questions unsuccessfully: If one looks at the map, all of the development, including the new Lincoln 40, shares a similar proximity to I-80 and the railroad as the entire Nishi property.  Why was it so easy to ignore air quality issues when the CC approved Lincoln 40?  Why isn’t the city concerned about the student housing and even more, the long-term residents all along Olive Drive?  What makes the Nishi property to the west of Richards Blvd. so magical as to attract and hold pollutants that doesn’t seem to be in effect on the east side of Richards Blvd.? 

    Todd, you would probably make more sense if you simply argued that we should condemn all property along Olive Drive between the railroad and I-80, evacuate all residences and turn it into a wood lot buffer with I-80.

  6. Todd Edelman

    Thanks, Dave. As you can tell from my texts herein, I am all about compromise.

    But I don’t think any property needs to be destroyed: Every single residence within about 500′ should be converted for commercial use, with all the air hygiene methods we’ve discussed ad coughium.

    Best case scenario – in lieu of societal collapse or the intense re-invigoration of sustainable degrowth (décroissance) – the I-80 will – three or four decades sense – have little to no tailpipe-originated emissions. But brakes will still dissolve slowly, and tires will always make noise over pavement, and metal will still bend the air pressure.

    In the context of the Northern California Megaregion electric railway with 10 to 15 minute headways / one hour to SF, the I-80 3.0 will mostly be a feeder for it, and used by regional electric buses – stopping at my proposed regional and local intermodal center near 80 and Richards – that serve areas as necessary not on the railway corridor and by properly taxed private and shared electric automobiles, plus local freight traffic.

    At that point the windmill-tilting, flying monkey Grand Eisenhower Emissions Barrier will still need to remove very nearly all pollution still occurring – gaseous, particular and vibrational – and it will still be a great location for solar panels, which by then will have much great efficiency than now and so – combined with residential and commercial energy use reductions – will produce perhaps 50% of the City’s electricity.

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