Délta Hydor cistern system
| Délta Hydor cistern system | |
Σύστημα Δεξαμενών Δέλτα Ὕδωρ | |
 A declassified photograph of government and city officials touring one of the primary chambers beneath the Administrative District upon completion, 1675 AN. | |
| General information | |
|---|---|
| Status | Operational |
| Type | Subterranean cistern complex |
| Location | Astérapolis, Prosgeiosi Basileus |
| Country | Constancia |
| Construction started | 1667 AN |
| Completed | 1692 AN |
| Cost | Classified |
| Owner | Ministry for Crown Lands |
| Dimensions | |
| Other dimensions | 47 chambers |
| Design and construction | |
| Architect | Hydrotechnical Bureau |
| Structural engineer | Imperial Constancian Armed Forces |
| Services engineer | ESB Engineering |
| Main contractor | ESB Construction |
| Other information | |
| Seating capacity | 18+ million cubic meters |
The Délta Hydor cistern system (Constancian: Σύστημα Δεξαμενών Δέλτα Ὕδωρ, "Delta Water") is a subterranean water storage facility beneath Astérapolis, Prosgeiosi Basileus, ranking among the largest such installations in Eura. Constructed between 1667 AN and 1692 AN, the system provides the ceremonial capital with strategic water reserves officially stated as sufficient for twelve months of normal consumption, though actual capacity substantially exceeds this figure.
History
The project originated in directives issued by the Permanent Standing Committee during the first year of Astérapolis's construction. Military planners recognized that an island capital, while defensible against conventional assault, remained vulnerable to siege if water supplies could be interdicted. The natural aquifer beneath Idolgi provided limited capacity, and surface collection was subject to seasonal variation.
Design responsibility fell to the Hydrotechnical Bureau, a specialized unit established within the Ministry for Crown Lands and staffed by engineers from the Imperial Constancian Armed Forces and civilian technical institutions. No foreign consultants participated; the project was conducted entirely using Constancian technical standards. ESB Construction was contracted to supply tunneling equipment, construction materials, and project management.
Construction
Work proceeded in four phases. Phase One (1667 AN-1674 AN) excavated the primary chamber complex beneath the Administrative District, creating eleven chambers ranging from 80 to 120 meters in length, 15 to 25 meters in width, and 12 to 18 meters in height. Phase Two (1674 AN-1682 AN) extended the tunnel network to connect primary chambers with secondary storage nodes. Phase Three (1682 AN-1688 AN) installed pumping, filtration, and distribution infrastructure. Phase Four (1688 AN-1692 AN) completed waterproofing, monitoring systems, and filling tests.
Infrastructure
The completed system encompasses 47 chambers with a combined volume exceeding 18 million cubic meters. Water enters from three sources: direct rainfall collection, desalinated water from the Constancia AquaTech facility, and treated greywater. Chambers are cut into limestone substrate, lined with hydraulite cement and ceramic tile.
A major component of the system is the separated stormwater and sewerage network installed concurrently with the cistern construction. This dual-pipe system directs rainwater to the cisterns for storage while routing sewage to treatment facilities operated by Eura Sewerage Business. Three advanced water treatment complexes, located in the Harbor District, Commercial Quarter, and near the Bridge-Tunnel terminus, process both incoming water for potable use and outgoing wastewater before discharge. ESB Engineering maintains the treatment facilities under contract with the Ministry for Crown Lands.
Strategic functions
The chamber network provides emergency shelter capacity for approximately 200,000 persons, with designated areas equipped with ventilation, lighting, and sanitation facilities. The Ministry for Civil Defense maintains evacuation procedures for the cistern system, though these have never been activated. The adjacent Stathmós Enérgeias Astérapolis, an Alexandrium power facility completed in 1751 AN, provides emergency power to the cistern's pumping systems.
Access remains restricted to authorized personnel, with maintenance conducted by specialized crews under Hydrotechnical Bureau certification.
