Houston, we have a problem. 休士頓，我們有麻煩了。
The oil and gas rich city, which is also the fourth largest in the U.S., now wants to live clean, and not green, but clean. 這個富含汽油與天然氣的城市，也是全美第四大城，現在希望過著乾淨的生活，不求環保，乾淨就好。
As part of our week-long series The City, 在我們為期一週的「那個城市」系列報導中，
CNN talks to Houston's mayor to see how residents are looking at energy in a whole new light. CNN 訪問了休士頓的市長，看看居民如何以全新的觀點看待能源。
I'm Annise Parker. I am mayor of Houston, Texas, United States of America. 我是安妮斯．帕克。我是美國德州休士頓的市長。
We're the fourth largest city in the United States. 我們是全美第四大城，
We have to provide essential city services to millions of people every day. 每天必須提供數百萬人必要的市區服務。
We are on the banks of Buffalo Bayou. 我們現在在水牛河的河岸上。
Buffalo Bayou was where Houston was founded. 水牛河區是休士頓建城的發源地。
We were where the railroads met the sea and the ships came up this bayou, you see a little bit farther here, and off-loaded. 這裡過去是鐵路與海交會的地方，船隻會沿河而上，你看稍遠的這邊，然後卸貨。
This is restoring the banks. It's opening up green space, putting some meanders back in the river that were originally straightened. 這是河岸的重建工程，開放了更多綠地，把一些曲流放回原本被取直的河中。
It'll clear the water up, be better for the fish and the turtles that live in here, but it will also be great for flood control. 這能讓河水變乾淨，對生活在其中的魚類、龜類比較好，也對洪水控制大有幫助。
Just because some mistake was made in the past doesn't mean you have to live with it forever. You can go back and fix it. 就因為過去犯了錯，並不表示你必須從此認命。你可以回頭改正它。
Just because we have built a city on the profits of oil and gas doesn't mean that we don't respect the environment, care about the environment. 就因為我們靠著石油和天然氣的獲利建立了一個城市，並不表示我們不尊重環境、不關心環境。
We've cut our greenhouse gas emissions by 26 percent and we are going to continue to lead by example. 我們已經減少溫室氣體排放達百分之二十六，而我們將繼續帶頭以身作則。
We're standing in front of Houston B-Cycle. 我們現在站在休士頓的 B-Cycle 前面。
It is a bike share, or bike rental program for the city of Houston. 這是公用自行車，或者說是休士頓市的自行車租賃計畫。
It's just over a year old and it is [has] just exploded in popularity. 這個計畫才實行一年多，已相當受歡迎。
We went from three stations to now 22 stations and 200 bikes. 我們從三座租車站到現在有二十二座、二百部自行車。
We want to expand the bike share through the more dense areas of inner-city Houston. 我們想擴大讓公用自行車分佈到休士頓市內人口較密集的區域。
We have 2,400 signalized intersections across the city of Houston, and it burns a lot of energy. 休士頓市各地有二千四百個有交通號誌的十字路口，消耗掉很多能源。
We originally decided to invest in LED lights, because we would save energy. 我們原本決定投入金錢用 LED 燈，是因為可以節省能源。
But what we found out -- LED lights last longer and they have to be changed out less frequently. 不過我們發現，LED 燈壽命比較長，需要更換的頻率也比較低。
So the return on investment is almost immediate. 所以投資幾乎立刻有了回報。
In my view, a sustainable city is a city that can project into the future that the air quality stays high and the water quality stays high, 在我看來，永續城市是一座能展望未來的城市，未來的空氣品質能保持良好、水質保持良好，
that there are [there's] a range of housing options for people to live in the city. 生活在城市裡的人們有各種各樣的居住選擇。
A sustainable city is a city that works today, but is building and investing for tomorrow. 永續城市是一座在今天運作良好、而且為明天建設與投資的城市。