思考与写作strongtowns.org
为什么许多城市没有钱
Why Many Cities Have No Money
2017 — 2020，它一次次回到首页
黑点是上首页（≥ 50 分）的那次投稿，空心点是没冲上去的投稿，点越大分数越高。
导读
Strong Towns 的这篇文章以路易斯安那州拉法耶特市为例，解释美国许多城市财政吃紧的根源：城市通过横向扩张获取新增长的即时收入（许可费、房产税、销售税等），却同时背上维护全部新基础设施的长期义务，作者称之为'增长庞氏骗局'。一旦增长放缓，维护成本远超税收，城市便难以为继。
为什么经久不衰：它用一个简洁、可证伪的模型解释了美国城市普遍面临的基础设施维护债务问题，多年来被反复引用，今天仍是理解郊区蔓延与市政财政困境的经典框架。
HN 评论精选
认同'增长庞氏骗局'模型：它简洁、可证伪，能解释美国各城市普遍的基础设施维护困境。
引用原文：'事情发生的方式很简单。在 Strong Towns，我们称之为增长庞氏骗局。通过联邦激励、州项目和私人资本的结合，城市得以通过横向扩张快速增长。这带来新增长的即时收入——许可费、公用事业费、房产税增加、销售税——作为交换，城市承担起服务和维护所有新基础设施的长期责任。钱在当下很管用，而未来的义务嘛……还很遥远。'这是 Strong Towns 看待美国城市的视角，是一个有用且可证伪的模型，解释力很强。该假说认为美国基础设施问题的根源是上级政府对下级的基建补贴，结果总是一样：基础设施无法维护，因为其成本从未被计入。Strong Towns 网站满是实例，拉法耶特只是其中之一。住在美国任何城市，你都很可能发现增长庞氏在起作用。另外那张 3D 地图应该把地方政客吓坏了。
aazaa查看英文原文
> The way this happened is pretty simple. At Strong Towns, we call it the Growth Ponzi Scheme. Through a combination of federal incentives, state programs and private capital, cities were able to rapidly grow by expanding horizontally. This provided the local government with the immediate revenues that come from new growth -- permit fees, utility fees, property tax increases, sales tax -- and, in exchange, the city takes on the long term responsibility of servicing and maintaining all the new infrastructure. The money comes in handy in the present while the future obligation is, well....a long time in the future. This is the lens through which Strong Towns views the country's cities. It's a useful model that explains a great deal. It's also falsifiable. The growth Ponzi scheme hypothesis says that the source of America's infrastructure problems is subsidies from higher levels of governments (e.g., federal) to lower levels (e.g., cities) for infrastructure. The outcome is always the same: infrastructure that can't be maintained because its costs were never accounted for. The Strong Towns website is chock full of examples, and Lafayette LA is just one. At this point if you live in any US city it seems pretty likely that you'll find a Growth Ponzi at work. Also, that 3D map should scare the liver out of local politicians.
质疑文章的数学：按其数字推算维护投入仅占所需的 4%，不合常理，可能是作者的推理有误。
引用原文数据：拉法耶特房屋中位价约 15 万美元，此类家庭每年缴税约 1500 美元，其中约 10%（150 美元）用于基础设施维护；而要维护已建成的道路和排水系统，每年需增税 3300 美元。据我判断，作者的意思是拉法耶特在道路和排水维护上的投入只达到所需的约 4%（150/(3300+150)）。这看起来难以置信。我怀疑他做了一个奇怪的假设：'目前 10% 的税收用于基础设施维护，因此增税 3300 美元后也只有 10% 用于维护。'这种推理或许能解释他'每年需增税 3300 美元'的说法。
jbullock35查看英文原文
> The median house in Lafayette costs roughly $150,000. A family living in this house would currently pay about $1,500 per year in taxes to the local government of which 10%, approximately $150, goes to maintenance of infrastructure [...] To maintain just the roads and drainage systems that have already been built, the family in that median house would need to have their taxes increase by $3,300 per year. As best I can tell, the author was saying that Lafayette is spending only $150 / ($3300 + $150) =~ 4% of what it needs to spend to maintain its roads and drainage systems. That seems implausible. I wonder whether he has made an odd assumption: "currently, 10% of taxes go to maintenance of infrastructure; thus, if we increase taxes by $3,300, only 10% of the increase will go to maintenance of infrastructure." That odd reasoning might account for his "need to have their taxes increase by $3,300 per year" claim.
认为美国让城市仅靠房产税负担基础设施是独有且短视的做法，忽视了城市对更大区域的正外部性。
指望基础设施的维护和更新完全由城市靠房产税来负担，似乎是美国独有的做法。城市不仅是为周边地区提供服务的贸易枢纽，还因高收入居民集中而成为税收'甜味剂'，对地区、省或国家都有正外部性。我确信市政管理中会有腐败，但强迫城市仅靠房产税等来为基础设施买单，而不像世界其他地方那样由省/国家用所得税拨款，是极其短视的。
sfifs查看英文原文
It seems to be a uniquely American practice to expect infrastructure maintenance and renewal to be funded by cities exclusively using property taxes. Cities generally act not only as trading hubs providing services to the region surrounding them, they also act as tax revenue sweeteners due to higher concentration of high income residents. Ie. they have positive externalities for the region, province or nation. While I'm certain there would be a level of corruption in city administration, it seems to be incredibly short sighted to force cities to fund infrastructure through only property taxes and such without funding from income tax the province/nation collects as what happens in other parts of the world.
质疑为何基础设施成本被视为不可降低，呼吁在管道和铺路技术上寻求创新。
基础设施的问题我关注一段时间了，确实如此。在我所在的地区，因为铺装路面太贵，他们正把柏油路砸回碎石路。让我着迷的是，基础设施成本无法降低似乎成了定论。我们真的已经找到了铺设/更换下水道、燃气、水管和道路最省钱、最可持续的方法了吗？在制造更容易更换、无需挖开整条路的管道方面真的一点创新空间都没有了吗？在如何以更低成本铺出足够平整或更耐用的路面上，真的没有好点子了吗？顺便说，也许我们应该能铺出一种径流更少、更能承受轻微沉降而不开裂大坑的路。我倒想知道，当事情真的恶化、大片人口的道路被砸回碎石时，会不会逼出一些新想法。
windlep查看英文原文
I've seen the infrastructure thing come up for awhile now, and it's definitely true. In my area, as in others I've read of, they're smashing paved roads into gravel roads as the paved are too expensive. The thing that fascinates me is that it feels like a forgone conclusion that infrastructure costs cannot be made cheaper. Have we really hit the most cost effective, cheapest, most sustainable method of laying/replacing sewer/gas/water lines and roads? There's no innovation left at all when it comes to making pipes that are more easily replaceable without digging the entire road up? There's no brilliant ideas left at all on how to 'pave' roads so they're smooth enough in a way that costs less money, or lasts way longer? Heck, while we're talking improvements maybe we should have a way to pave a road such that we don't have such massive runoff and its more resilient to minor settling underneath without opening large potholes. I do wonder whether the shit really hitting the fan, and massive chunks of the population having their roads smashed back to gravel might shake a few new ideas out.
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