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Habitat Pressures and Risk Areas - #2 Roads

Roads are important to the people of Alaska, and provide vital transportation corridors for commerce and recreation. At the same time they serve the needs of Alaskans, road construction and maintenance pose one of the greatest threats to the health of wild Copper River salmon and their habitat. Every culvert, materials sites, waste site, fill area and haul road can affect wild salmon populations if improperly designed, constructed or maintained.

Poor design and construction practices, the use of undersized bridges and culverts, wetland fills and stream diversions, bank hardening, and the lack of state of the science sediment and erosion control practices contribute directly to the loss of available high quality salmon habitat. Undersized culverts impede or completely block fish passage. Wetland fills, stream diversions, and bank hardening speed water velocities, reduce primary productivity, and usually result in direct loss of productive salmon habitat. Sediment in the water reduces the capacity of rearing habitat, and when deposited in spawning areas greatly reduces egg to fry survival. Roads that closely parallel rivers and streams provide long "exposure zones" for potential impacts. These are all common problems along roads and trails, electrical transmission lines, and within subdivisions in the study area.

TRAILS: Areas that previously saw little use are now often accessed by new trails that are blazed using new and better equipment. ATV use is primarily associated with hunting and access to mining claims, but spring and summer recreational use is rapidly increasing. Significant ATV impacts to wetlands and streams are occurring north of the Glenn Highway and the Tok Cutoff. On the Copper River Delta ATV use outside permitted areas may be increasing. The proliferation of trails and their potential impact on salmon and their habitat was a uniform assessment concern.

BRIDGES AND CULVERTS: The numerous undersized or poorly installed culverts not only impede fish passage, they also are in constant need of repair and replacement because they often cannot adequately handle periodic high water flows.

The following information was developed from an unpublished ADF&G data set that represented a field inventory of culverts. The data set lists 244 culverts within the Copper River watershed. Each site may have more than one culvert, e.g. if two culverts are sitting side by side. According to the inventory, 64% of the culverts block the passage of fish, 32% of the culverts may not pass fish, and only 4% of the culverts provide adequate passage for fish.

SEDIMENT AND EROSION CONTROL: Alaskan construction projects often feature sediment and erosion control practices that lack technical design and are not an integral part of the project plan. Storm water runoff from roads, subdivisions, parking areas, and outlet structures go largely unregulated and unmonitored. Although storm water runoff is not a universal threat, in some specific localities and over time, serious problems may result. This situation is evident on areas surrounding Eyak Lake, in Cordova. Here, road construction, gravel pit operation and subdivision development take place without drainage plans and without sediment and erosion control. A significant amount of sediment is discharged to spawning and rearing habitat. This same situation is found in lake and streamside developments throughout the watershed. Similarly, disposal of roadway and parking lot snow in streams, lakes, and wetlands is a common practice, and can accelerate lake and spawning area siltation.

SUBDIVISIONS AND LAND USE: Subdivisions can have the same impacts on wild salmon as roads, especially when located adjacent to spawning areas, wetlands and lakes. Within the study area there is significant pressure for the development of new subdivisions, and the areas proposed are almost universally within or adjacent to salmon habitat. Sediments and septic tank discharge can impact water quality and salmon. Areas noted as potentially or currently under development include Eyak Lake, Paxson Lake, Summit Lake, Crosswind Lake, Mentasta Lake, Long Lake, Copper and Tanada Lakes. These are the kinds of places we all like to live.

BANK HARDENING: Rock riprap (a loose barrage of stones usually 18-25 inches in diameter) remains the preferred method of bank protection for federal, state and private riparian property owners. Nearly all bridges, culverts and roadway banks adjacent to streams have large riprap placed on the banks. Hardened banks provide little protection for salmon fry, making them vulnerable to predation.

STREAM DIVERSIONS AND WETLAND FILLS: For road construction, acquiring right-of-way to avoid impacts to streams and wetlands important to fish and wildlife is often problematic. Budgetary constraints, unwilling owners and sometimes-unforgiving terrain results in using alternatives, such as wetland fill and stream diversions. As an example, at the Chistochina Bridge replacement project a high water channel of the Copper River will be diverted and approximately 50 acres of wetlands adjacent to the Copper River will be filled.

REDUCTION OF RISKS: Roads, Trails and subdivisions will continue to be developed and maintained within the watershed. Management for habitat rather than management by agency would help reduce impacts of development on future salmon generations. The key to maintaining healthy salmon habitat is in proper design, construction and maintenance of developments. A collaborative effort to share information, knowledge and management protocols across agency and governmental jurisdictions can help. Uniform development policy, careful planning and permitting, and adequate enforcement capacity would eliminate most threats.

Culverts & Fish Passage
Planning Area	Total # of Culverts	Not Passable		May Not Be Passable		Passable		Uncategorized
		#	%	#	%	#	%	#	%
Bering Glacier	0	0	0	0	0	0	0	0	0
Central Copper	24	19	79	3	13	0	0	2	8
Copper River Delta	115	59	51	39	34	4	3	13	11
Chitina		0	0	0	0	0	0	0	0
Gulkana	24	12	50	7	29	1	4	4	17
Klutina	0	0	0	0	0	0	0	0	0
Metnasta Chistochina	20	7	35	8	40	0	0	5	25
Mount Sanford	3	3	100	0	0	0	0	0	0
Tazlina Nelchina	11	6	55	3	27	2	18	0	0
Tonsina	41	33	80	4	10	2	5	2	5
Wrangell	6	0	0	5	83	0	0	1	17
Totals	244	139	57	69	28	9	4	27	11

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