SEPA RULES
DETERMINATION OF NONSIGNIFICANCE
DESCRIPTION OF PROPOSAL: Rocky Coulee Tent Camping Recreation Area.
RCW 197-11-970
DETERMINATION OF NONSIGNIFICANCE
DESCRIPTION OF PROPOSAL: Rocky Coulee Tent Camping Recreation Area.
No formal marine improvements are planned at the Rocky Coulee Tent Camping
Recreation Area site.
The 5.6 acre site consists of a degraded access road, informal parking area, and a user
defined network of natural surface trails running for approximately 550 feet south along
the riparian vegetation on the west bank of the Columbia River. In several locations the
user defined trails extend into the riparian areas to informal campsites and fire rings. The paved access to the site, Recreation Drive, ends where the former highway extends into
the river.
The preliminary findings suggest that the structures included in the proposed
improvements can be founded on either outburst flood deposits or basalt rock.
Grant PUD will improve the existing project site to provide two picnic sites, two ADA
Compliant Toilets, ten Campsites and 18 parking sites. Current informal trails will be
restored and formal trails developed and delineated. Land restoration will occur
throughout the project site once construction is completed.
1. Demolition
Demolition related to upland improvements includes removal of pavement along the former highway alignment, removal of a portion of site fencing, removal of portable toilet concrete bases, culvert removal, tree removal, and relocation and improvements to an existing sign.
2. Upland Site Improvements
The improvements to the upland facilities generally occur more than 15 feet horizontally from ordinary high water (+575 feet) with the exception of a shoreline access trail and two benches.
A paved access road that will serve the internal ADA parking area proximate to a double vault toilet and two ADA campsites is proposed. This road will be served by Recreation Drive and will cross the existing drainage channel that is adjacent to and parallels Recreation Drive. The proposed road will utilize a bottomless aluminum arch culvert to span an existing drainage channel. This culvert will have an open bottom to reduce impacts to the existing channel bottom. The proposed aluminum culvert will not impact the current incised channel of Rocky Coulee, except during installation and construction of the access roadway. Currently, there is an existing concrete box culvert upstream of the proposed crossing. The proposed aluminum box culvert will have a cross sectional area (end area) equivalent to the existing, upstream culvert. Additionally, the proposed culvert will have hydraulic characteristics that will provide additional capacity when compared to the upstream concrete box culvert.
Access Road
Existing Conditions:
Access to the site is from Recreation Drive. Recreation Drive ends at the Columbia
River. The existing asphalt surface narrows and ends approximately 20 feet landward of
OHW. The asphalt is currently in poor condition. Basalt rock placed on the surface
serves as a vehicle barrier to prevent vehicles with boats from continuing down the old
roadbed.
Proposed Improvements:
The site access road, Recreation Drive, will follow the existing alignment. The pavement will be cut and removed along the north and south edges of the existing, resulting in a narrower road. A gravel and planted filter strip will be installed on both sides of the roadbed to improve water quality from stormwater runoff. A majority of the existing pavement along the entrance road will be rubbilized and mixed into the base of the proposed Hot Mix Asphalt (HMA or asphalt) pavement section. No improvements to the access road are proposed outside of the Priest Rapids Project Boundary.
Vehicle Turn-Around
Existing Conditions:
No designated vehicle turn-around currently exists on the site. Vehicles currently use the existing degraded asphalt and gravel surface area at the end of Recreation Drive to turn around.
Proposed Improvements:
The proposed HMA paved vehicle turn-around will be located at the terminus of
Recreation Drive. The existing degraded asphalt and gravel area at the terminus of
Recreation Drive will be rubbilized and mixed into the base of the proposed asphalt
pavement section.
Auto Parking
Existing Conditions:
Auto parking occurs along the existing Recreation Drive. Visitors park along the southern edge of the paved and gravel surface and next to the top of bank of the Columbia River at the road’s end.
Proposed Improvements:
The proposed auto parking area will be gravel and asphalt pavement. Proposed parking
stalls are located a minimum of 120 feet from OHW. The 14 passenger vehicle stalls
adjacent to and on the north side of Recreation Drive will be gravel; in addition two ADA
accessible stalls adjacent to Recreation Drive will be asphalt; and the ADA parking
accessed from the south spur road will be asphalt. Gravel parking spaces will be
delineated with concrete wheel stops. ADA parking spaces will be delineated with
signage, striping and concrete wheel stops. Stormwater runoff will be directed, to the
extent possible, to gravel and/or vegetated filtration strips.
Tent Camp Sites
Existing Conditions:
A number of informal user-defined campsites exist on the site. These areas have
impacted the native soils and upland and riparian vegetation. Users have also
constructed rock fire rings.
Proposed Improvements:
The ten proposed tent campsites include designated concrete and gravel surface areas
intended to minimize user impacts to the site. An 8” wide concrete border will define the
gravel tent pads. A tent site, picnic table, and barbeque grill will be installed at each
campsite. Two ADA accessible campsites with ADA picnic tables are included in the
improvements. The tent sites will be accessed via stabilized gravel, concrete, or natural
surface trails. When practical, user defined trails will be improved for continued use. All
user-defined trails not improved as a part of the project along with other user defined
impacts will be restored with native vegetation.
Picnic Areas and Vault Toilets
Existing Conditions:
2 picnic tables are currently installed at the site. Portable toilets and 55 gallon trash
receptacles are placed at the site during the recreation season. The 2 portable toilets are secured to 6 inch thick concrete bases that are left at the site year round.
Proposed Improvements:
A proposed centrally located picnic area will include two ADA accessible picnic tables.
An additional picnic area is planned on the northeastern trail spur and will access 3
tables. Picnic tables are also located at each of the ten campsites. Additional trash
receptacles may be added at the picnic area. Two picnic sites have been designed to
accommodate a picnic shelter as part of a future site improvement. A single vault toilet will be placed along the north edge of Recreation Drive approximately 111 feet from the ordinary high water line. The below grade storage vault for the restroom facility will be installed in an approximately 8 feet deep excavation and backfilled with suitable native material or import backfill. An additional double vault toilet will be placed proximate to the proposed tent sites and the ADA campground parking approximately 225 feet from the ordinary high water line.
Stabilized Gravel Trail
Existing Conditions:
An extensive network of existing trails extends south of Recreation Drive for
approximately 550 feet into the site. The trails are user-defined informal paths that vary
in width from 1 foot to as much as 6 feet in width. The trail network provides connections to the riparian zone and shoreline in several locations, segmenting habitat. No formalized shoreline access points are reached by the user-defined trails.
Proposed Improvements:
The proposed trail improvements at the site will formalize acceptable routes to the
designated picnic areas, campsites, and vault toilets. Approximately 1,800 linear feet of
trail of various widths (3, 5, and 8 feet) will connect the campsites, vault toilets, picnic
areas, and parking. A portion of the 5 and 8 feet wide sections of trail will be constructed of concrete. The remaining trails will be constructed of stabilized gravel or site soils and will meet ADA accessibility guidelines. The 3 feet wide section of trail will be constructed of stabilized site soils and will meet ADA Accessibility guidelines.
Two benches will be installed along the northeast trail spur on the existing jetty.
Rocky Coulee Culvert
Existing Conditions:
No formal crossings of Rocky Coulee exist at the project site. User defined paths leads
from the existing site signage down slope and across the coulee to the south. The trail is utilized to access the existing picnic tables and user defined informal campsites. There is a single culvert immediately up gradient west of the project site. The culvert is a box culvert 38 feet long, 8 feet high and 10 feet wide made of mortared basalt. The cross sectional area at flowing full is 80 square feet. The inlet and outlet have wing walls at 45-degree angles, extending approximately 10 feet up-channel. The outlet has a concrete apron extending approximately 17 feet down gradient of the outlet. The approximate inlet and outlet elevations are 631 feet and 627 feet, respectively, taken from Google Earth. The other culvert is over 2,600 feet up gradient of the proposed culvert’s location and was installed to allow Recreation Drive to cross the channel.
Proposed Improvements:
The proposed culvert location is approximately 135 feet up gradient of the OHW
(575.0’+/- NAVD88) of the Columbia River. The maximum pool elevation of the
Wanapum Pool is 578.6 feet. The channel is vegetated with sagebrush and bunch
grasses above approximate elevation 579 feet. The channel bottom ranges between 10
and 12 feet in width and 1 to 2 feet deep in the vicinity of the proposed culvert location.
The channel section is trapezoidal, with 2H:1V side slopes adjacent to Recreation Drive, and side slopes ranging from 4H:1V to 10H:1V on the opposite side of the channel. The top width of the channel is approximately 22 feet. In the vicinity of the proposed culvert, the channel alignment is fairly straight and parallels Recreation Drive. The ground surface elevation at the proposed culvert outlet is 579.5 feet. The ground surface elevation at the inlet is 580.0 feet. The channel grade at the location of the proposed culvert is approximately 1.2%. The proposed culvert is a bottomless aluminum low profile arch culvert 22 feet in length with a span of 25 feet 2 inches and a rise of 6 feet 2 inches. The culvert will be installed such that the bottom width will measure 24 feet 8 inches and the highest point of the arch will measure 4 feet 10 inches high from the finished ground surface. Construction of the culvert will require temporary excavation for the foundation. The channel bottom section will be modified from existing to achieve 80 square feet of cross sectional area. Overall, the channel bottom will be lower than existing conditions. No fill of the channel is proposed. The culvert will have 45-degree wingwalls at the inlet and outlet. The culvert
foundation and wingwalls will be protected from scour by riprap armor placed along the
edges of these features. Design of the foundation, wingwalls, and related scour
protection has not yet been scoped. No armoring of the channel bed is proposed.
Culvert crossing under Recreation Drive
Existing Conditions:
There is an existing culvert crossing under recreation drive approximately located at the
user defined entrance to the upland portion of the site. This existing culvert is a 12 inch
concrete pipe. This pipe was installed to drain runoff from the north of Recreation drive
into Rocky Coulee. Currently, the inlet at the north side of Recreation Drive is buried and does not appear to allow runoff to pass under Recreation Drive.
Proposed Improvements:
The proposed 18 inch LCPE culvert will be located at the west end of the proposed
parking along Recreation Drive. This culvert will be used to convey runoff from the north
side of Recreation Drive into Rocky Coulee.
PROPONENT: Public Utility District No. 2 of Grant County, Washington
LOCATION OF PROPOSAL, INCLUDING STREET ADDRESS, IF ANY:
This site is located on the right bank (west) side of the Columbia River, 1.1 miles upstream of the I-90 bridge crossing at the old Highway 10 West site. From Vantage, take Hwy 10 West to Recreation Drive, turn Right on Recreation Drive. Travel to road end at Columbia River. The site is located in Sections 18 and 19, Township 17 North, Range 23 EWM, Kittitas County, Washington.
LEAD AGENCY: Public Utility District No. 2 of Grant County, Washington
The lead agency for this proposal has determined that it does not have a probable significant adverse impact on the environment. An environmental impact statement (EIS) is not required under RCW 43.21C.030 (2)(c). This decision was made after review of a completed environmental checklist and other information on file with the lead agency. This information is available to the public on request.
o There is no comment period for this DNS.
o This DNS is issued after using the optional DNS process in WAC 197-11-355. There is no further comment period on the DNS.
6 This DNS is issued under WAC 197–11–340(2); the lead agency will not act on this proposal for 14 days from the date below. Comments must be submitted by April 04, 2013 5:00 PM Pacific Standard Time.
Responsible official: J. Darrell Pock
Position/title: Project Specialist III
Phone: (509) 754-5098
Address: P.O. Box 878
30 C St. SW
Ephrata, WA 98823
Date: 3/14/2013 Signature: /s/_______________________________
J. Darrell Pock, Project Specialist III
6 There is no agency appeal.
#03076/2953361/2953392
Pub.: March 21 & 28, 2013