Monday, December 23, 2013

The Google Bus thing...

There's an old saying in real-estate: Drive until you qualify. The idea is you're supposed to start looking for housing close to work, and drive away from the office until you can afford to buy housing. Something has gone horribly, horribly wrong with that concept in San Francisco and Silicon Valley...or perhaps, it isn't so wrong: People are working in the tech companies in the Valley and choosing to live in San Francisco, 30+ miles away.

These well-paid employees are driving rents in San Francisco and even Oakland through the roof, and the companies are employing private shuttle service down the peninsula to the offices to make it more attractive. People are getting kicked out of their homes. A friend of mine shared this article about a bus that was held up by protesters today, and a window was smashed. It has links to other articles about similar incidents, and this is clearly escalating in a fashion that makes the Somerville Kill a Yuppie sentiment seem really minor. As far as I know, nobody has smashed windows on the private Alewife Shuttle that services my office park on 128 in suburban Boston.'ll get no contest from me on the idea that it's not right that the shuttles use the MUNI stops for free. You'll get no arguments that gentrification doesn't almost always have a huge downside or that the companies that do move their offices into downtown San Francisco don't create massive dead zones if they don't play nice with their neighbors. You certainly won't get me complaining about the unwashed masses like this guy did.

However, it is what it is: Silicon Valley is the center of the tech industry, which is exceptionally big business right now. It follows that that puts a lot of pressure on housing costs. It follows from there that people will be priced out of places they'd like to live, and perhaps even have been living. The bigger question is what should be done?

It seems to me that too much of the focus has been on how to get rid of These People and keep them and their private yuppie buses out of the city instead of trying to figure out how to get it to work. At the end of the day, the 'techies' (the term I keep seeing in the media for those of us Who Are Those People) are citizens that are just trying to do their jobs, live their lives, and do both in the best way possible. I don't get why the employees, instead of the employers and the involved municipalities (or the landlords), are taking any of the blame. I never thought I'd see the day where a very liberal population is waging war on mass transit, but that's what's happening here. For decades, we've lamented the death of our inner cities, and now that money is pouring into (some of) them, we don't like that.

Sure, I don't live in San Francisco. I live on the opposite coast, but really...even if they are the self-centered autistic robots the detractors are saying they are, it shouldn't really matter: cities are dynamic places that should be able to adjust to and accommodate all types of people, as long as the city itelf can adjust and grow.

San Francisco was famously overrun by the counterculture in the 1960s, pushing out a lot of people. New development happened elsewhere; life went on. The story of changing demographics in cities and the winners and losers is as old as cities. The problem always seems to be the worst when there is nowhere for people to grow to, which can only happen--aside from lags as it takes a lot more time to build than for economies to change--when natural growth is repressed.

If the influx of these nerdy rich white and Asian men who aren't really that into granola OR family life is a problem, it seems to me that the only solution here is to begin allowing denser development in the region and investing more in transit so that the city can grow and adjust. Even if there was more land to build sprawl on, these new residents don't want it. San Francisco itself is physically tiny and already very dense. It's smaller and denser than Boston! You're not going to cool housing demand without increasing housing supply. Why isn't that the conversation? Perhaps if the Valley was more like San Francisco, more people would want to live there instead of the doing the 30 mile hump down the peninsula every day to work. However, then the entrenched interests in the cul-du-sacs of the Valley would be upset instead.

Huge side-track about why I think tech workers and the suburbs are not great partners after the jump.

Sunday, November 17, 2013

MSPaint and Minimum Lot Size

I've had a few discussions lately around "Preserving the character of a town", ecology, and minimum lot size. People like to say that requiring larger lots leads to a more "rural" feel, and I disagree. I'm not going to pretend to use science here, but bear with me. I've also talked about some of the social aspects before, but I couldn't avoid digging into them again.

Compare these two communities:

* Disclaimer: Actually used Photoshop for the histogram to calculate color coverage and not MSPaint.

Both of these places are about 80% Green, open land. The top one (City) is about 6.3% red houses and the bottom one (Burb) is 4.75%. The remainder is roads: 14.3% in the top one, 15.1% in the bottom one.

Which one of these two communities is likely to have open space like operating farms or walking trails? Large sections of undisturbed land for wildlife habitat? City of course. Also, City has a higher population by at least 20% (more houses, assuming none are apartments, which are illegal in Burb) and possibly less money spent on road maintenance (fewer roads).

Why is it then that suburban communities do everything they can to look like the bottom map in the name of "preserving character?"

Let's say these two communities are in the same market. Assuming houses can't be built on existing roads because they'd be illegally close by town law, Burb is essentially full, whereas City is still half empty (Keep in mind that both are technically 80% open). If there is a demand for 1% more map coverage in housing, what happens? City absorbs most of it, and those who want the extra private space Burb offers push up the prices in that community, pushing those who can no longer afford it out. Those who prefer denser living have no problem finding affordable housing in City. The two communities begin to homogenize internally, and vary wildly externally. What if those that work in Burb can no longer afford to live there? Tough: Spend extra on a car and gas and commute from City to a community where you are not welcome as a voting citizen.

Meanwhile, Burb argues that they can't provide a nice community and a high-quality school system if they allow people of lesser means who pay less in taxes on smaller properties into the town, and there is merit to this.

Of course, no city around here looks like City, with the massive empty area around it (a Green Belt). Some cities elsewhere in the country and certainly in Europe look like that. Why? In a major metro like Boston with cold weather and rocky soil, housing is the most productive use for the land. Not farms (which are more productive and certainly more cost-effective elsewhere), and certainly not nothing at all. The only way to maintain empty land when there is a demand for more housing is to use the force of law to somehow make sure nothing is built on it. Aside from the lot size minimums used in Massachusetts, Portland, Oregon is famous in the US for legally requiring a Green Belt around the city while allowing high densities inside of it...this of course has its proponents and detractors as it creates some bizarre distortions of its own.

The liberals should hate the state-sponsored inequality here, and the libertarians should hate the government manipulation of markets. Does that mean the current system is entirely wrong? Not quite...

The only way to not require the force of law here would be to loosen the growth restriction laws that created these bizarre maps in the first place and allow supply to increase in-line with demand organically. If the demand for housing goes up the combined 2% coverage we're talking about and Burb didn't have exclusionary zoning laws in place, some people would subdivide their lots at a personal profit and allow new growth to occur. That, of course, fundamentally would alter the neighborhood for those who did not subdivide. There are two huge downsides for neighbors here: They now live in a place they didn't chose to live in, and if the new houses are--for whatever reason--a negative on property values, they have been injured in their most important investment on top of that. Others would build on huge lots in City and destroy the open space. Clearly, completely unrestricted growth isn't a great idea, either...for these reasons and many others.

However: Growth has been the story in the world for a very, very long time. We should expect it to continue. The way I see it we have two choices: Continue to sprawl outward and destroy the environment while ghettoizing an underclass in state-sponsored poverty zones, or liberalize our land use laws somewhat in places where it makes the most sense: near jobs, existing dense areas, and transit centers. This would certainly cause some pain for some people as the rules of the economic game change, but as a society, I figure we win... if only burb looked at it that way. I wonder who in this fictional town would protest the gaining of a large park and an expanded tax base (20% growth, now the same as City) with about 15-20% of the land of the city being changed:

Saturday, September 21, 2013

Two Way Street Restoration - Why are we here?

Lowell has been very seriously been considering the restoration of two-way traffic downtown. I think it's impossible to not be skeptical about this, as traffic often gets choked-up today and it doesn't seem like an apparent reduction in capacity could do anything but make the situation worse.

I'm not going to argue point-by-point if it should or shouldn't be done (but for the record, I'm for giving it a try as we have professional engineers with experience doing this sort of project saying it'll be fine): I want to talk about how we got here: Why did the streets become one-way and why change back?

Let's go back to the end of World War II.

War-time rationing and mobilization put an end to the growth of the domestic automobile industry for the duration of the war. Once it was over, the United States found itself as the only major industrial power still standing, with a newly expanded middle-class, and a love for technological progress (after all, we were the only country with The Bomb).

Add the GI Bill and the Baby Boom to the economic expansion we were having, and the conditions were right for the real, earnest beginnings of what we think of today as Suburbia. The construction of Levittown, New York began in 1947, and in the mid-1950s Eisenhower signed into law the Federal-Aid Highway Act.

The Car was here to stay, and was going to be front-and-center in the lives of every American family:

Levittown, PA
Eisenhower receiving a 10-year highway plan 
Shoppers World, Framingham, 1951
First corporate McDonald's, 1955
The general idea seemed to still be that people would commute into traditional downtowns to work and shop. They would need to be able to get there, and they would be doing it by car. To this goal, Lowell—already reeling from a collapsing industrial base which the end of wartime production accelerated—would be brought into...The Future.

The Future, 1962
So, in the 1950s, we began re-designing Lowell around the car. I got to visit the Department of Planning and Development library and leafed through A Master Plan of Highways for the Lowell, Lawrence, and Haverhill Metropolitan Areas, May 1956. In it, the highway that was then called a replacement for MA-110 and today is I-495 was laid out. It was a research piece on to re-think the cities of the Merrimack Valley to handle the traffic load of the 1980s.

By the time of its publication, the streets downtown had already been reconfigured as one-ways the year before, and were viewed as a great success. According to the National Bridge Database, the VFW Highway was built in 1949 and the Hunt's Falls Bridge in 1954. However, they would clearly not do in The Future. Keep in mind all these maps were made at times when there was no computer-aided design!

First, some overview maps. Note the proposed Lowell Connector and its extension through Back Central and into Downtown. Also Note the Lord Overpass area (which of course was largely built), and the new roads through both Lower Belvidere and Christian Hill to service the just-built Hunt's Falls Bridge.

495, Lowell Connector, and various street changes in green.
The intersection of 3, 495, and the Lowell Connector. Note the Gorham St ramp instead of Woburn St
Central Lowell, proposed changes in green

Some close-ups:

A demolition of large parts of downtown intended to make it easier to drive through it as quickly as possible. 
A help with context. Bye-bye old police station, Saab building, Pollard's Exchange. Hello more one-way high-speed roads!

Who needs Back Central?!

What became the Lord Overpass, and some changes the the Dutton/Thorndike intersection that did not happen.
An Artist's Rendering thereof. It sure looks swell!
There is zero consideration here for what it means to be a person and to walk places, and to be in an enjoyable, humanized environment...because that's not part of the equation. It's all about accommodating the car: how can we reconfigure our city to make it easier to get to Chelmsford from Dracut as quickly as possible?

To be fair, if you look at some of the proposed alignments in the current Rourke Bridge Study, not every crazy proposal is to be seriously considered. However, even the most overkill early proposals in that study—none of which made it too far into serious consideration—could hold a candle to the types of plans drawn up in the 1950s-70s. At that time, a lot of what was proposed for Lowell was quite serious, and up to and through the 1970s, the plans for getting us into The Future accelerated.

The world of 1997, in 1965.
This is a plan from the 1970s, for what became the Sampson Connector (Thorndike/Fletcher/Dutton):

Scheme D for Thorndike/Fletcher/Dutton. This was considered the most rational plan. A maze of ramps removes the at-grade intersection, makes Fletcher St one way, makes Adams and Suffolk Streets dead ends, etc.

A highway to the Acre?
Lowell, for reasons that are well documented, had every reason to look for any way out of its socioeconomic situation in the 1960s and 1970s. Bulldozing half the city might've just saved it they figured. Of course, at some point in the 1970s, things started to go a bit south for the car-craze. The miracle technology started to become a little less shiny, and the problems it directly brought became clearer:
Gas Shortage, 1979
Moratorium on highway construction inside of 128, 1970

So, what did we learn?

Unquestionably, the car enabled the suburbs. I'm going to basically skip over the obvious sidetrack of the other side of mid-century urban issues: Laws, policies, and social phenomenons such as blockbustingredlining, failed housing projects, white flight, and deindustrialization. They all have some ties to the rise of the car. The relationships are far too complex for me to even pretend to take a stab at.

The end result of all of this is that at some point we came to realize that our places started being made for the car, instead of the car being a tool to get around our places. These places are disjointed, inhuman, and ugly. It just isn't always worth the slightly easier drive. Books, of course have been written on this, such as The Geography of Nowhere. Think about New York, San Francisco, or Boston and how few expressways there are. Think about how much nicer Boston feels with the Artery underground. Compare these very nice cities to places like Detroit with great expressway access. Highways have been shown to be bad for people and society and should be built very sparingly.

So, over the past few decades, we've come to value The Past in how we look at our built environment. Time-tested systems of how people interact with their environments in a happy and healthy way have regained focus over the irrational-exuberance of the car age. Perhaps it's partially nostalgia: we are in a poor economy with an uncertain future after all. However, a lot of it is also about learning from our mistakes misusing the technology of cars.

One-way streets are often seen as one of those mistakes. They make streets feel like highways instead of places for people. They make it so people don't see many businesses as they're funneled into a particular set of roads going in one direction, and a different set on the way back. They're disorienting to visitors. They're just plain overused and should be an absolute last resort and not a preemptive miracle cure, which is what they were used for in the past.

Saturday, March 23, 2013

The Merrimack River - Renewable Energy

We all know that hydroelectric power is renewable energy. As an engineer of a sort and historian of a different sort, I've been asked a few times what the actual hydroelectric power potential of the Merrimack River at Lowell is. Many months ago I did a post that covered some of this. However, I don't quite trust my math and that wasn't the pure focus of that post, so I decided to do another one.

The questions are:

  1. How much power - at peak - can the Merrimack theoretically provide? Because of large seasonal variations in flow, this number can vary by a magnitude. So, we are also interested in how much power, in dry spells, it can reliably provide.
  2. How much water can go through the canal system? This number I figure should be very close to the historical figures. We've all seen in the summer that the river underneath the Pawtucket Falls Bridge is bone dry as it is all diverted into the canals. In the spring, there's a ton of water down there that is not being used for any mechanical purposes. 
  3. How much electricity does Lowell currently produce off of the Merrimack, at various sites around the city?
  4. Are there ways to produce more power we haven't implemented?
The first figures aren't hard to get. We just need to go to the USGS website and look at some flow figures for Lowell, since waterpower is a simple formula of volume times drop times weight of the water.

Total Power Available

So, we'll start here. This is the statistics for the amount of water in the Merrimack River below the Concord River. So, this isn't really at the point we are interested in, but for our purposes, it should be fine. You can surf around the site if you'd like, but it seems like the Concord River contributes maybe 10% of the water volume at this point, so we'll be within reason to use these figures and maybe round down as appropriate.

Two numbers in this chart are the most important: High flow and low flow.

Low flow, in August, is about 2,500 cfs (cubic feet per second). This is the reliable amount of energy available to the city. We can assume that due to the dam and lock system, the height of the canals, that is, the drop part of the equation, is constant.

High flow, in April, is nearly ten times that: 22,000 cfs. Again, the canal and dam system controls the level of the water in the system.

Now, that formula. I'm going to mention Patrick Malone's excellent Waterpower in Lowell book, which, in addition to having extensive data on the water the mills used (we'll get back to that), and the way it was captured, utilized, and researched, contains the formula I mentioned above. It also mentions, as we are often told, that the Merrimack River drops about 30 feet at Lowell and water weighs 62.4 lbs per cubic foot.

So, on the low end, we're talking about

2,500 cfs * 62.4 lbs per cf * 30 ft = 4,680,000 lb-ft per second.

Now, let's step back to high school physics. What is a pound-foot per second?

Well, a foot-pound is a unit of energy, equal to 1.356 Joules. A Joule per second is a Watt, a measure of power. So...let's convert foot-pounds to joules:

4,680,000 lb-ft * 1.356 = 6,345,228 joules

Since we're interested in joules per second, the number is directly equivalent to a watt. Our math says that at lowest flow, Lowell can expect 6.35 MW of power from the river before we factor in the energy efficiency of a turbine (which can be as high as 90%). That's a lot of lightbulbs! A horsepower is 746 watts so we're talking 8,509 horsepower, or a few dozen cars. Let that sink in as you think about gasoline: If you drive a 250hp car, your car produces about 1/30 the guaranteed power available from the entire Merrimack River at one of the best sites for an industrial city in the nation.

Now, sometimes the drop in the river is listed as 32 or even 34 feet. What's that do to these numbers? 34 feet is 7.19 MW.

Now, high flow:

22,000 cfs * 62.4 lbs per cf * 30 ft * 1.356 = 55.85 MW. Much better!

How much power is this?

Well...the US Energy Information Administration says that the average Massachusetts house uses 618 kilowatt hours a month. Let's assume that's ballpark for Lowell. Note that electricity usage is low in the Northeast because of the lack of electric heat and heavy air conditioning use. If you're using 618 kw/h a month, you're using 20.6 kw/h a day, or about 0.85 kw/h an hour. The hours cancel out so that's an instantaneous draw of 0.85 KW, or 850 Watts. You could run 850 homes on a Megawatt then, or over 5,000 homes off of the reliable energy the river can produce. Multiply by 10 for the high flow data. There are about 106,000 people in Lowell, and it looks like reasonable estimates are 30,000 households (which isn't exactly a house but close enough for us). That's one in six we could power, and that includes no other electricity uses from businesses and factories to street lights.

For comparison, the Natural Gas plant on Tanner Street, L'energia, produces 80 MW peak. The Coal/Petroleum plant on Salem Harbor is 750 MW peak. Seabrook Nuclear Power Station is 1,200 MW peak!

So, how much can the canals harness?

Again, as far as we've gotten is that the low flow for the river is 2,500 CFS. We know all of that water can get into the canal system. We know when there is a lot more than that, it flows over the top of the dam unused. We don't know how much the system can actually produce. The best way to find out the answer to this question is to look at historical data: back to Malone's book.

The thing to remember here is that in early Lowell, water was a utility. James B Francis, the most famous of the Locks and Canals engineers, the "Chief of Police of Water", really had to know how much water he had and could provide each mill so he could provide it to them reliably - and charge them for it. There was a standard unit for sale called the Mill Power, which was equivalent to 25 cubic feet per second of water falling 30 feet, or 85 theoretical horsepower. Malone has all this data. At the build-out of the canal system, Lowell produced a reliable 140 "Permanent" Mill Powers, which would be 11,900 horsepower, or 15.95 MW. This is three times the expected minimum (but under a third of spring flow), which is why the dam systems were needed to keep the water levels high enough during the day - we turn the river into a giant mill pond that refills overnight if need be. Mill companies were allowed to buy extra water when it was available, and in 1859 (after the system was completed and before heavy use of steam power), Lowell was often using an extra 40 Mill Powers. Let's call that an easy extra six Megawatts for 22 MW. There is complex engineering related to flow rates lowering head and becoming counterproductive, plus backed-up water slowing wheels when the river was high - for the book.

How much is installed?

Well, Locks and Canals, the company that provided the water, eventually ended up being owned by Italian energy conglomerate Enel. Enel, as Boott Hydroelectric, has a few sites in Lowell's mills as well as the main plant on the Northern Canal by the University Ave Bridge. Their statistics are surprisingly missing from the EIA map above, but they provide it here.

Their main plant uses 3300 cfs of water and drops it 37 feet. Using our formula to check their math, we get 10.33 MW. This is considerably lower than the 17.3 MW installed they claim here and there is no explanation for the gap. However, adding in the supplemental plants in the old mills, we get to 20.7 MW installed. If we take Lowell's historic max with surplus mill powers of 22 MW and we multiply by an efficiency factor of 90%, we get 19.8 MW... which is essentially what Enel says they can produce at maximum.

What I'm seeing is that if they are producing this power regularly, we are using all of the available water Lowell historically has had and this is not enough electricity, even in high water scenarios, to run the residential sector of the city.

Is there more somewhere?

An interesting fact about hydro power is that the technologies, because turbines are so efficient, haven't changed much since Francis was doing his experiments 150 years ago. Is there anywhere else we can squeeze out any more power at any price? Raising the dam would work, but we would flood out our neighbors upriver. There probably isn't much extra summer water, as we're already in control of the water all the way up the Merrimack's watershed to its source at Winnipesaukee.

The only way to get power out of water is to utilize its kinetic energy - it has to be moving. The Wikipedia article on hydraulic head provides a good graphic showing how a turbine, like those in Lowell, work. If you've ever seen a boat on the Merrimack in Tyngsboro or up by the Rourke Bridge up to the buoys above the dam, you know there isn't much motion to that water - it's being backed up by the dam. Go too much downstream, and you hit the 17 MW Lawrence dam installation - again, the water is not moving much above this point.

However, you have to wonder if during the summer months if it would be cost effective to install small run-of-the-river installations to catch the more-than-half of the power potential the river has. 

However, I'm not going to pretend to know anything about the math on that ;-)

In conclusion...

It would appear we are using the majority of water that Lowell has ever had available to it for power generation purposes already, and, while not an insignificant amount, is not anywhere near the electricity needs of the modern city...never mind its resource-poor suburbs. Always, always be conscious about claims of renewables replacing our dwindling fossil fuel reserves.