Let’s set some things up so that we’re all caught up:

In 2015, the apocalypse happened; rising sea levels compounded with the Black Flu (deadliest pandemic in human history killing billions around the world) wiped out the modern world. Every nation has collapsed and the “old world” for all intense and purposes is gone.

Fast forward 10 years later to 2025; the US Government has managed to survive (if barely) and has reconstructed itself around the Peak Eight National Command Complex/PENCCOM, a White House-Capitol-Supreme Court-Pentagon hybrid super bunker. Despite its name, PENCCOM is actually located roughly 50 miles from the actual Peak Eight Mountain in Northern California, with PENCCOM being situated in the southwestern Oregon mountain ranges.

Desperate survivors, refugees, etc. flocked to PENCCOM and soon enough, a small community camping outside of the massive underground bunker-fortress became a bustling small city of over 117,600 citizens by 2025, forming what is known as the Colony.

For the most part, the US Government in PENCCOM tries it’s best to emulate the old world US Government by embracing and being fanatically devoted to the values and ideals of the Declaration of Independence and keeping the Constitution as it is. However, changes were made:

• For one, the Colony is divided into 13 individual Districts, with PENCCOM acting as the nucleus of the Colony. With a population of 117,600, there’s currently 24 Representatives in the US House of Representatives, with each person representing roughly 5,000 people.

The Senate meanwhile, still follows the rule of two Senators from each state (or in this case, District), giving the US Senate 26 Senators.

• The executive branch of the government has reshaped into the following:

**Department of Domestic Affairs **
The Department of Domestic Affairs is a result of the unification of the Departments of Housing and Urban Development, Agriculture, Labor, Energy, Interior, Health and Human Services, and Education. They’re now known as the:

• 
  Strategic National Resources Reserves


• Bureau of Infrastructure


• Bureau of Agriculture


• Bureau of Labor and Manpower


• Bureau of Public Health and Security


• Bureau of Energy

Department of State

Department of National Defense
The Department of National Defense is a result of the unification of the Departments of Defense, Homeland Security, Veterans Affairs, and Transportation. The former departments above are now known as the:

• 
  Strategic National Military Resources Reserves


• Bureau of the National Garrison


• Bureau of Homeland Security


• Bureau of Veteran’s Affairs


• 
  Bureau of Military-Civil Defense Infrastructure

Department of Justice

Department of Commerce

What you have actually created is a very large and elaborate city government, which in a post apocalyptic environment will rapidly draw the ire and resentment of the population because it sucks up so much of the resources just needed to survive.

If they truly want to be a Federal government and reconstitute the United States of America, they will be more focused on sending out expeditions to the territories of the United States, conducting a census and a survey of all remaining resources (capital and human), and working to establish networks that encourage and bind people to accept the Government of the United States rather than the warlord of Omaha, Nebraska as the legitimate governing body.

This may involve some pretty imaginative working, from rebuilding the US Post office (a legitimate function that everyone would see a use for) to perhaps negotiating with the local warlords and appointing them territorial governors, or at worst, becoming allies with some and devoting the remaining resources of the US military to assist the warlord in crushing other warlords.

Given the low population density and the collapse of economic, social and most political organizations, there seems very little point in recreating the States, rather the Government might administer them as US territories, much like they did in the 1700's and 1800's until there was a critical mass of people to recreate a State, and with it the need for Representatives and Senators.

So the post apocalyptic government may more resemble the American government from the Declaration of Independence to the "closing of the frontiers" in about 1880. They will focus on such critical tasks as communications, surveying land and resources, national defense, administering law (there will be a US Marshal's office and circuit judges, but no FBI, for example) and whatever is left of international diplomacy and relations. There will be few taxpayers, and few resources to administer a large and complex bureaucracy, nor much of a need. The Federal Register of laws and regulations will become extremely stripped down to reflect this as well.

The post apocalyptic US government will be in a very precarious situation, covering a vast expanse of the continent with few resources. In a post apocalyptic environment, they may face both foreign and domestic challengers to their sovereignty (What happens if Canada moves to take the Oregon territories? What does the US government do if Russia, Japan and China are involved in a war over fishing rights off San Francisco, while the Mexican Empire moves to reclaim Alta Mexico? What if the Warlord of Denver declares themselves the "Emperor of the Rockies"?).

Your environment does have room for lots of "urban" storytelling in the local environment, but a would be national government is likely going to focus on the large scale issues, not local governance.

Too many representatives!

For a town a little bigger than Redding, California your town is pretty representative-heavy. Redding has 20 divisions of city government listed on its website and yours seem a reasonable approximation. Your city has 50 elected representatives and Redding has 5.

I see you are trying to echo the constitution in your setup but that is a boatload of representatives. Maybe it could work if they were semiceremonial, like the loya jirga in Afghanistan. If I were setting up the city I would have a small number of full timers and assemble the entire 50 only on very special occasions.

Side note: where are these 100,000 folks getting their food?

The United States Government was created assuming low-tech conditions. Nothing in the constitution relies upon high technology/energy and the laws that do rely upon this infrastructure can be revoked.

The post apocaliptic government must be more federalist then the current USG is because of distances and bad communications and the different issues at different regions rebuilding the country.

No

this question boils down to two things.

1. Can they feed themselves, which is up to you and how you set up the society.




2. Can they replace tools as they wear out. This is a no. Due to being more or less confined to a single location and its resources, even if they have the machinery they will not have hte raw resources. But they likely won't have the machinery or expertise either, the population is just too small. which means a collapse back to a more medieval technological level, which makes many of the bureaus and departments pointless and makes a single centralized city unsustainable.

There are a few problems with premise:

• If you get an epidemics that wipes out most of mankind, then you may declare the issue of AGW solved.




• The question clings on implicit assumption that US government is right now functioning properly. Let's say it's a controversial issue.




• it is a bit weird that survivor cosplay US government in one tiny city, instead of taking advantage of all whose free real estate in depopulated areas.

So what you have here is here is whether such state could function?

• Size? OK. What you have is a small city state. Can work neatly, just good luck in having any effective control over contemporary US territory. (presumably if other people are mostly dead is not an issue)




• US constitution was intended for a federation and NOT for a city state. For practical purposes, it would be a bit awkward to try to separate all those functions between local and federal government




• merging those all departments - advisable, otherwise you may end with a departments with a few people each




• government structure - actually there is a good reason to recreate good old days for legitimacy purposes, thus it should be a valid strategy.