Chapter 22: Hydrology — Rivers and Lakes of Théxar
"Rivers are the blood vessels of the planet. They carry life from the mountains to the oceans and back, in the clouds. To stop a river is to stop the heart of Théxar." — "Book of the Cycle," Xha'Ruun
Related sections: → see [Ch.14, "Oceans of Théxar"], → see [Ch.13, "Continents"], → see [Ch.21, "Ecosystems"] Key principle: Théxar's river network totals ~244 thous. мо. 12 major river systems, 8 largest lakes. Fresh water — 2.8% of the hydrosphere, including groundwater and glaciers.
Introduction
Fresh water makes up only 2.8% of Théxar's entire hydrosphere, but it is the foundation of terrestrial life. Rivers, lakes, groundwater, and glaciers form a single hydrological network connecting the oceans with the continents.
22.1 River Systems
22.1.1 Largest Rivers
TABLE 22.1: Largest Rivers of Théxar
River Continent Length (мо) Watershed (thous. мо²) Discharge (ша³/s) Mouth Khar-Tor Kharak 870 75.2 33,400 Serrin Sea Thash-Ven Rhuval 776 59.9 25,800 Gharra Ocean Sharrus Vexar 638 40.5 17,800 Gharra Ocean Thar Kharak 602 46.3 28,300 Serrin Sea Ven-Mor Kharak 498 29.7 12,300 Thalas Ocean Irkhen Rhuval 443 22.3 9,440 Irkhen Sea Khal-Mor Vexar 378 17.4 7,440 Gharra Ocean Rhu-Ven Rhuval 350 15.7 6,530 Irkhen Sea Ser-Ven Kharak 313 12.0 5,080 Thalas Ocean Xha-Mor Vexar 260 8.68 3,450 Gharra Ocean
22.1.2 Khar-Tor River
The largest river on the planet. It originates from the glaciers of the Khar-Tor range at an altitude of 7,560 ша and empties into the Serrin Sea. Its basin covers ~7.7% of the Kharak continent.
Hydrological regime:
- Recharge: glacial (45%) + rain (40%) + groundwater (15%)
- High water: the high-water season, discharge up to 69,000 ша³/s
- Low water: the low-water season, discharge 11,300 ша³/s
- Solid runoff: ~194 billion кх/year (anomalously high due to volcanic ash)
Economic significance:
- Irrigation of 49.6 thous. мо² of agricultural land
- HEP cascade (6 stations, total capacity 48 power units)
- Navigable for 427 мо from the mouth
22.1.3 Thar River
The sacred river of Xha'Ruun civilization. On its banks arose the first settlements of proto-Kharites (→ see [EV-0001]). The capital Khar-Vexar is located in the Thar delta.
| Parameter | Value |
|---|---|
| Length | 602 мо |
| Drop | 5,850 ша |
| Discharge | 28,300 ша³/s |
| pH | 6.8–7.2 |
| H₂S (dissolved) | 0.02 mg/L |
22.2 Lakes
22.2.1 Largest Lakes
| Lake | Continent | Area (мо²) | Depth (ша) | Type | Feature |
|---|---|---|---|---|---|
| Mor-Ven | Kharak | 1,768 | 756 | Tectonic | Largest, freshwater |
| Thal-Koss | Rhuval | 1,173 | 463 | Volcanic | Hot springs |
| Ven-Shar | Vexar | 913 | 585 | Glacial | Cryptoendoliths |
| Khal-Ven | Kharak | 768 | 354 | Residual | Saline (7%) |
| Rhu-Mor | Rhuval | 587 | 256 | Floodplain | Biodiversity |
| Shan-Ur | Kharak | 487 | 104 | Crater | Meteorite |
| Thex-Mor | Vexar | 347 | 671 | Glacial | Deep glacial lake |
| Gharra-Ven | — (Khal-Tor isl.) | 198 | 220 | Volcanic | Caldera |
22.2.2 Lake Mor-Ven
The largest lake on the planet, located on the Central Plain of Kharak. The name means "time-water."
Characteristics:
- Area: 1,768 мо²
- Average depth: 390 ша
- Maximum: 756 ша
- Volume: ≈69 мо³
- Transparency: 14.6 ша (Secchi)
- pH: 7.4
Lake Mor-Ven is a center of freshwater species endemism: 45% of fish species are found nowhere else.
22.3 Groundwater
Total groundwater reserves of Théxar are estimated at ~70.5 thous. мо³.
| Type | Volume (thous. мо³) | Share | Age | Use |
|---|---|---|---|---|
| Soil water (active) | 23.5 | 33% | 1–10,000 years | Drinking, irrigation |
| Artesian | 30.2 | 43% | 10,000–100,000 years | Industry |
| Deep (relict) | 16.8 | 24% | >1 million cycles | Geothermal, mineral |
22.4 Hydrological Cycle
Hydrological cycle of Théxar
- Atmosphere
101 мо³
Water vapor: 0.5–2.0%
- Surface water
1 510 мо³
Rivers + lakes
- Groundwater
70.5 thousand мо³
| Process | Value |
|---|---|
| Evaporation | 56 па/year |
| Precipitation | 102 па/year |
| Runoff | 36 па/year |
| Infiltration | 22 па/year |
| Oceans — via rivers | 42 thousand мо³/year |
Atmosphere exchanges water with the surface; surface water connects with groundwater and the oceans. Evaporation and precipitation are opposing processes.
Fig. 22.1. Hydrological cycle of Théxar.
Chapter Summary
- Théxar's river network: 244 thous. мо, 12 major river systems.
- Largest river — Khar-Tor (870 мо).
- Largest lake — Mor-Ven (1,768 мо², 756 ша deep).
- Groundwater — 70.5 thous. мо³ .
- Annual river discharge into oceans — 42 thous. мо³.