SURVEY METHODOLOGY. April 15, Rob Livick City of Morro Bay Public Services Director/City Engineer 955 Shasta Avenue San Luis Obispo, CA 93401

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1 April 15, 2011 Rob Livick City of Morro Bay Public Services Director/City Engineer 955 Shasta Avenue San Luis Obispo, CA SUBJECT: Summary Letter Report for Tidewater Goby and Steelhead Monitoring for the Morro Creek Diversion Project in Morro Bay, San Luis Obispo County, California (SWCA#20734) Dear Mr. Livick: SWCA Environmental Consultants (SWCA) is pleased to present this letter report documenting the results of tidewater goby (Eucyclogobius newberryi) and steelhead (Oncorhynchus mykiss) surveys and monitoring for the Morro Creek Diversion Project (project), located in Morro Bay, San Luis Obispo County, California. The City of Morro Bay (City) requested that SWCA provide fisheries survey and relocation services once the City had obtained emergency permits from the U.S. Army Corp of Engineers (USACE), Regional Water Quality Control Board (RWQB), and California Department of Fish and Game (CDFG) to redirect Morro Creek to an east/west alignment so as to protect the City s Waste Water Treatment Plant (WWTP) outfall pipe. The pipe, located approximately 200 yards to the north, was exposed by Creek flows and scouring due to the Creek having taken a northerly alignment before turning west and entering the ocean. This letter report summarizes the methods and results of the surveys and monitoring. SURVEY METHODOLOGY Morro Creek provides suitable aquatic habitat for tidewater goby and steelhead, both federally listed fish species. SWCA biologists, Travis Belt and Barrett Holland, conducted stream surveys within Morro Creek prior to initiation of creek realignment activities on Surveys were initiated at 9:30 A.M. during a 4.4-foot high tide (9:53 A.M.) and continued through the 0.7-foot low tide (3:52 P.M.) until 6:00 P.M. Conditions during the survey were breezy, clear, and ranged from 55 to 70 degrees Fahrenheit. SWCA biologists sampled Morro Creek using dip and seine nets to identify fish species present upstream and downstream of the area to be realigned. Fish captured during pre-disturbance surveys were relocated approximately 300 yards upstream of the upstream portion of the area to be realigned using 5-gallon buckets (refer to Attachment A, Photo 1). SWCA biologists spoke with equipment operators and City WWTP personnel prior to the realignment work to discuss the importance of completing the breach before nightfall so fish species could be captured and identified during daylight hours. SWCA indicated that completing the realignment before nightfall would reduce the potential for take of federally listed fish species and/or any native fishes of Morro Creek. Once the diversion work had begun, SWCA biologists began capturing all fish species present downstream of the realignment. Fish species captured downstream were relocated 300 yards upstream of the realignment using 5-gallon buckets. As the tide dropped and the creek began to take its realigned east/west course to the ocean (refer to Attachment A, Photo 2), the isolated former alignment, downstream, began to subside into the former low flow channel and isolated pools began to form (refer to Attachment A, Photo 3). The now isolated former low flow channel and isolated pools were surveyed repeatedly for fish until 6:00 P.M. At this time, the 4.8-foot high tide began to push salt water back up the low flow channel and into areas previously surveyed and cleared of all fish species.

2 RESULTS Surveys of Morro Creek revealed the presence of two native fish species. Five threespine stickleback (Gasterosteus aculeatus) and 310 longjaw mudsuckers (Gillichthys mirabilis) were captured and relocated upstream of the breach (refer to Attachment A, Photo 4). Steelhead and tidewater goby were not indentified during the surveys of the Creek nor were any other sensitive species. Follow-up site visits to Morro Creek were conducted on April 2, 2011, by Mr. Holland at high and low tides to observe the effects of the tide and surf on the realigned channel as well as the continued absence of fish species in the isolated former creek channel. Mr. Holland observed that the tide and surf was pushing salt water up the newly realigned channel during high tide and scouring of the north bank of the new channel was occurring (refer to Attachment A, Photo 5). Mr. Holland also observed that high tides had begun to fill areas of the now isolated former channel of the creek; however, the entire isolated area still maintained connection to the ocean. Mr. Holland returned at low tide to inspect this same isolated area of the former alignment and no individual isolated areas that could strand fish were observed. The newly realigned channel was observed to be functioning as intended and the WWTP outfall pipe was covered with sand from the previous high tide. A final monitoring visit was conducted on April 4, 2011, at low tide to observe the isolated former channel of the Creek and no areas of concern were observed (refer to Attachment A, Photo 6). SWCA ENVIRONMENTAL CONSULTANTS 2

3 ATTACHMENT A. SWCA ENVIRONMENTAL CONSULTANTS

4 PHOTO 1: View of northerly flowing former alignment of Morro Creek and the new alignment (i.e., area being graded). Note stockpiling activities to prepare for closing-off the channel to be realigned. PHOTO 2: View of Morro Creek looking west at the newly aligned channel. SWCA ENVIRONMENTAL CONSULTANTS A - 1

5 PHOTO 3: View to the south of the former, now isolated portion of the channel. Note water subsiding into the low flow channel and isolated pool areas. PHOTO 4: Threespine stickleback captured during pre-disturbance surveys within Morro Creek. SWCA ENVIRONMENTAL CONSULTANTS A - 2

6 PHOTO 5: View of the newly realigned channel during high tide. Note scouring along the north bank of the new channel. April 2, PHOTO 6: View of the former, now isolated, northerly flowing channel. Water in photo is salt water that inundates the area during high tides. April 4, SWCA ENVIRONMENTAL CONSULTANTS A - 3