PUB00027

• Year: 1990
• Title: Final Report Rio Grande Water Supply Study, Phase 1
• CWCB Section: Interstate & Federal
• Author: San Luis Valley Water Conservancy District
• Description: Reconnaissance level determination of the physically and legally available flow at 4 reservoir sites in the Rio Grande Basin upstream of Del Norte, Colorado
• Publications - Doc Type: Brochure

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Rio Grande Compact

The Rio Grande Compact sets annual stateline delivery obligations for Colorado

based on the amount of flow at various gaging stations within Colorado. Compact

deliveries are not required to strictly adhere to the Compact delivery tables

on an annual basis and, therefore, the Compact provides for accounting of over-

deliveries (credits) or under-deliveries (debits) which may be carried forward

into subsequent years. Provisions of the Compact relate Colorado I s Compact

obligations and its accumulation of credits and debits to storage levels at Rio

Grande Project Storage, a major storage and irrigation project in New Mexico and

Texas.

Major provisions of the Compact affecting storable flows at the potential

reservoir site were investigated and translated into river basin model operating

criteria. For example, the model incorporated the capture, at a potential

reservoir site, of water which would have been required for Compact deliveries

and release of that water from storage if needed by the Rio Grande Project.

The Conejos obligation under the Compact was assumed to be separate from the Rio

Grande mainstem obligation (i.e. two river system). Since individual water uses

in the Conejos Basin were not modeled, the Conejos Basin was assumed to always

satisfy its Compact delivery obligation.

Another major provision of the Compact which may affect a new storage project

is that the Compact permits Colorado to increase consumptive uses of water of

the Rio Grande and Conejos River to the extent that water may be delivered at

the stateline from the Closed Basin. The Closed Basin Project which provides

such a delivery is described in the next section.

Closed Basin Project

The Closed Basin Project consists of numerous wells and a conveyance channel

designed to salvage and deliver from the Closed Basin to the Rio Grande, water

which would have been non-beneficially consumed. The total ultimate production

capacity of the Closed Basin Project is presently estimated to be approximately

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