Appendix C 

 Happy Valley Hydrology 



Regulatory Framework 



Montana Surface Water Oualit\' Standards: According to ARM 17.30.608 (l)(d), the Whitefish 

 River drainage and its tributaries are all classified as B-2. Among other criteria for B-2 waters, 

 no increases are allowed above naturally occurring levels of sediment, and moderate increases 

 are allowed over naturally occurring turbidity. "Naturally occurring," as defined by ARM 

 17.30.602 (17), includes conditions or materials present during runoff from developed land 

 where all reasonable land, soil and water conservation practices (commonly called BMPs) have 

 been applied. Reasonable practices include methods, measures or practices that protect present 

 and reasonably anticipated beneficial uses. These practices include but are not limited to 

 structural and non-structural controls and operation and maintenance procedures. Appropriate 

 practices may be applied before, during, or after completion of activities that may impact the 

 resource. 



There are no designated beneficial surface water uses within the project area due to a lack of 

 stream channels or delivery to downstream waters. 



Water Quality' Limited Waterbodies: The proposed project area is located within the Whitefish 

 River watershed. The Whitefish River is listed in the 1996 and 2002 List of Waterbodies in Need 

 of Total Maximum Daily Load (TMDL) Development publication produced by the Montana 

 Department of Environmental Quality (DEQ, 1996, 2002). The stream and draws found within the 

 project area are discontinuous and do not contribute surface flow to the Whitefish River. 



Montana Streamside Management Zone (SMZ) Law: By the definition in ARM 36.1 1.312(4)(b), 

 the discontinuous drainage feature running north to south through the proposed project area is a 

 class 3 stream. The stream has a defined channel, flows water for less than 6 months of the year, 

 but becomes sub-surface downstream from the project area and does not contribute flow to another 

 body of water. 



Water Quality 



The class 3 stream that flows through the project area appears to be primarily the result of runoff 

 from residential home and road construction to the north of the proposed project area. Ditches 

 constructed to channel road runoff and overland runoff from these residential areas deliver the 

 surface runoff to the stream found within the proposed project area. The flow from this runoff is 

 the source of surface flow in the channel, and may be what caused the channel formation to 

 occur. The stream is low gradient, stable, well vegetated with grass and sedges, and is not 

 actively eroding or down-cutting. No in-channel sources of sediment were identified during field 

 reconnaissance. 



The existing road system in the proposed project area is low standard, and does not currently 

 meet best management practices for surface drainage or erosion control. Some portions of the 

 road system are poorly located in draw bottoms. These conditions have created erosion 

 problems within the road system. In places, this erosion has been severe. Many reaches of road 

 are badly rutted, and are used by all-terrain vehicles and four wheel drive vehicles for "mud 

 bogging". This has led to severe erosion problems in places. A majority of this erosion remains 



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