What is the latest status of the project “National Underground Project”?

The status recorded for “National Underground Project” is Proposed.

What is the budget and commercial profile for the project “National Underground Project”?

Taiyo normalizes the budget of “National Underground Project” to USD 300000000.

Where can I verify the source and access all details for “National Underground Project”?

This Taiyo project page references Greater Greater Washington along with the original URL (https://ggwash.org/view/83268/the-national-underground-is-a-bad-idea-that-should-be-buried). Taiyo standardizes official data into a consistent, searchable project profile.

National Underground Project

Sector: Water Supply and Storage • Location: Washington, District of Columbia, United States

Source: Greater Greater Washington

Project

Proposed

The National Underground Project proposes a large concrete structure between the Smithsonian Castle and the Museum of Natural History, designed to serve as a floodwater cistern and parking facility. It aims to mitigate flooding concerns along Constitution Avenue by detaining stormwater and providing parking for vehicles, although it has faced criticism for its complexity and feasibility.

Status: Prospective
Sector: Water Supply and Storage, Cement, Automotive, Residential, Car parking
Location: Washington, District of Columbia, United States of America
Updated: 22 Jul 2026
Source: Greater Greater Washington

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Project Information

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The project “National Underground Project” is an infrastructure initiative in the Water Supply and Storage sector, located in Washington, District of Columbia, United States. Taiyo aggregates data on it from Greater Greater Washington.

Participants

Not available for this record.

Status

Original status	Proposed
Taiyo status	Prospective
Taiyo last update	2026-07-22

Contact

Not available for this record.

Description

Description	The National Underground Project proposes a large concrete structure between the Smithsonian Castle and the Museum of Natural History, designed to serve as a floodwater cistern and parking facility. It aims to mitigate flooding concerns along Constitution Avenue by detaining stormwater and providing parking for vehicles, although it has faced criticism for its complexity and feasibility.
Original sector	Flood Mitigation
Budget

Location

Country	United States of America (USA)
State	District of Columbia
City	Washington

Source

Source	Greater Greater Washington
URL

More Details

Record type	Project
Sector	Water Supply and Storage, Cement, Automotive, Residential, Car parking
Article published date	2025-03-20

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National Underground Project

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