Dam, Diversion PRACTICE INTRODUCTION USDA, Natural Resources Conservation Service - practice code 348

DEFINITION damaging flows to another watercourse A diversion dam is a structure built to that is more stable or otherwise more divert all or part of the water from a capable of reducing damage. One of the watercourse into another watercourse for more common uses of this practice is conservation purposes. diverting water from a stream or river into PRACTICE INFORMATION a canal used for irrigation purposes. A diversion dam is designed to divert The impacts of a proposed diversion dam water from a watercourse such as a are evaluated to assure water quality, fish waterway or stream into another and wildlife, aesthetics, and other watercourse, irrigation canal, stream, environmental concerns are considered in water-spreading system, or another the design and layout of the structure (s). waterway. The practice is also carefully evaluated to The purpose of the practice is to improve assure compliance with state and local the beneficial use of water, or divert laws concerning natural watercourses. Additional information including design criteria and specifications are in the local NRCS Field Office Technical Guide. Initial Setting: Watercourse Dam, Diversion Dam, Diversion (348) where controlled water 06/22/12 diversion is desired. Start

Irrigation Water Conveyance (428 Series) Stable A structure that diverts all or part of the Outlets: Grassed Waterway (412) Irrigation Storage Reservoir water from a waterway or a stream. (436) Underground Outlet (620)

Irrigation Regulating Reservoir Redirected water flow (552) Infiltration Outlet (associated treatment)

D.2 (+) crop production D.1 (-) Stream flow

I.1 (+) Net return to 1.3 (+) Sediments and farmer sediment-borne I.4 (-) Downstream I.6 (+) water I.7 (-) Aquatic I.8 (-) Extent and contaminants flooding temperatures habitat quality quality of riparian and quantity areas

I.2 (+) Maintenance of drainage ditches I.5 (+) Stream bank and other structures erosion I.10 (+) Upland I.9 (-) Aesthetic Fish Passage (396) habitat quality of streams fragmentation

LEGEND

I.11 (-) Quality of Mitigating practice or receiving waters I.13 (-) Wildlife food activity I.12 (-) Fishable and and cover swimmable waters. Associated practice

#. Created by practice

D. Direct effect C.3 (-) Aquatic and C.1 (+) Income and C.2 (+/-) Public health terrestrial ecosystem I. Indirect effect income stability and safety diversity and function C. Cumulative effect

Pathway

(+) increase; (-) decrease