Compensatory Mitigation Monitoring Report Aquatic Habitat Improvement City of Montrose Whitewater Park, Montrose County, Colorado March 6, 2014 i. Project Overview 1. USACE # # SPK 2013 00851 2. Permittee: City of Montrose (433 S. 1 st Street. Montrose, Colorado 81401) Mr. Scott Murphy, City Engineer. Phone (970) 901 1792 (smurphy@ci.montrose.co.us) Monitoring By: Ecological Resource Consultants Inc. (ERC). David Blauch, Senior Ecologist (303) 679 4820 (dave@erccolorado.net) 3. Project Description The Aquatic Habitat Improvement project is intended as compensatory mitigation for construction of a whitewater park that will span approximately 950 linear feet of the Uncompahgre River at Riverbottom Park within the City of Montrose. The whitewater park includes the placement of six whitewater rock drop structures, un grouted scoured rock toe armoring, un grouted rock bank work, and temporary dewatering areas, totaling approximately 3,000 cubic yards of dredged and fill material. The compensatory mitigation aquatic habitat improvement project (subject of this monitoring report) includes improvement features within approximately 1,540 linear feet of the Uncompahgre River immediately upstream of the planned whitewater park. Aquatic habitat improvements consist of creation of four individual riffle/pool/glide sequences and the reshaping of approximately 1.7 acres of existing streambed. The aquatic habitat improvement project also replaces previously constructed (2006) grant funded aquatic habitat improvements that were situated within the footprint of the whitewater park. 4. Location The project site is located at Riverbottom Park (immediately upstream of the pedestrian bridge and fishing pier), in the Uncompahgre River, within Section 33, Township 49 North, Range 9 West, New Mexico PM, Latitude 38.46382, Longitude 1 07.87943, City of Montrose, Montrose County, Colorado. 5. Completion Date February 21, 2014. (Aquatic Habitat Improvement Mitigation Only) 6. Performance As built condition built per design plan. Additional monitoring will be Standards Met required to determine long term achievement of performance standards. 7. Corrective Actions As built condition. No corrective or remedial actions required. 8. Recommendations As built condition. No recommendations at this time. Monitoring will continue by the spring of 2015. Notes: a. This monitoring report has been completed in accordance with USACE RGL No. 08 03. b. Construction commenced on 2/10/14 and was completed on 2/21/14. No significant deviations from the design plan were made during the construction activities. All created features are shown on the enclosed 2014 Monitoring Map (Figure 1).
ii. Monitoring Requirements Special Condition 2 of the Permit requires within 60 days following construction activities, postconstruction site photographs of the mitigation site, showing work conducted be submitted to the USACE. Photographs comparing the pre project and as built condition are provided herein. Special Condition 3 of the Permit requires submittal of annual monitoring reports detailing success of the aquatic habitat improvement site to the USACE by December 31 st for three years following completion of the construction, and for each additional year, if remediation is required. The report must follow RGL No. 08 03 and must contain repeatable surveys of four defined stream cross sections, a longitudinal profile and photos taken from permanent photo points. This as built monitoring report is intended as the first of three annual monitoring reports which outlines a monitoring protocol and results as specified. Special condition 4 of the Permit states the aquatic habitat improvement requirement will be considered successful once, after three years post construction, representatives of the USACE and CPW have determined that the site has been constructed as approved and that impacts to fish habitat from the whitewater park have been fully compensated. This monitoring protocol and annual report submittals to the USACE and CPW are intended to assist in making this determination. Summary of Monitoring Protocol Performance criteria are standards that are used to evaluate measurable aspects of the improved system and indicate the success of a project at achieving its stated goal of aquatic habitat improvement. This mitigation project focused on altering the physical characteristics of the river channel for the specific purpose of creating a variety of instream aquatic habitat. Two individual physical parameters; 1) channel profile and 2) channel cross section were selected for annual monitoring based on the ability to effectively and cost efficiently measure project success as it relates to the altered physical characteristics. In addition, visual observations and photo documentation will be completed to further provide more qualitative documentation of condition and success. Parameter 1: Channel Profile The channel profile provides a good indication of the overall channel bed stability. A stable channel is defined as one that has the ability to transport its flow and sediment load over time without either aggrading or degrading. If the profile remains relatively constant, it can be inferred that sediment is being transported efficiently. Method of Measurement The channel profile (at primary feature points) was surveyed as part of the initial monitoring program (as built condition). The survey will be completed in subsequent years with results from each year compared with previous years to detect changes in the profile. Evaluating Results Local adjustments to the channel profile should be expected from year to year. This will be especially true following the 2014 seasonal high flows as this will be the time when the natural system (flows, sediment, substrate and overall stream gradient) adjusts the constructed system. The improvements will be viewed successful if, over time, the constructed riffle/pool/glide sequences are 2
evident in the profile and no major areas of aggradation or degradation are identified. These as built results will be compared with future surveys to assist in evaluating success. Parameter 2: Channel Cross section The improved channel is generally narrower and deeper for a given flow than prior to improvements. Measuring the channel cross section provides a method of evaluating whether the new channel remains at its designed width and shape. Channel width also provides a measure of whether flow depths were increased during low flow periods which was a primary goal of the improvement project. Method of Measurement Four permanent channel cross sectional monitoring locations were established by installing rebar set in concrete along the banks to denote the surveyed locations. The elevations along the cross sections were tied into the construction datum to allow for comparison in future years. The survey will be completed in subsequent years with results from each year compared with previous years to detect changes in the channel cross section. Evaluating Results Local adjustments to the channel cross sections should be expected from year to year. This will be especially true following 2014 seasonal high flows results as side slopes will seek their stable configurations. The restoration will be viewed successful if, over time, the width and shape remains relatively constant. Parameter 3: Visual Observation and Photo Documentation The improved channel included four (4) constructed riffle/pool/glide sequences that are intended to create a variety of habitat types critical to local fish populations that were lacking. The riffle/pool/glide sequence were constructed in combination with channel reshaping to create a low flow channel within the main channel to improve instream habitat during times of limited flows. In addition, boulder habitat clusters were strategically located to increase instream, structural diversity and available habitat. Method of Measurement The condition of the constructed instream habitat will be evaluated through a combination of photographic documentation, visual inspection and general observation of aquatic life utilizing the different river features. It will also be evaluated based on the sustainability of channel forms (riffles, pools and glides) and the variety of habitat provided. Eight (8) permanent photo points have been established. Evaluating Results The condition of the created instream features will be compared from year to year to determine whether the constructed habitat is in place and continuing to function as designed. Visual observations will be made and compared from year to year to qualitatively determine whether habitat variety is being maintained including, deep pools, silt free, oxygenated riffles, slower moving glide sections and instream boulder habitat clusters. This parameter is the most subjective and results will be given in a qualitative manner. iii. Summary Data The following graphs, tables and photographs provide a summary of data collected as part of the monitoring requirements and protocol outlined above. 3
Table 1. Profile Survey Data Summary Survey Date Feature Design 2/10/2014 2/21/2014 ID STA Pre Elev AS Built Elev RB 1 6610 5810.1 5810.2 RE 1 6480 5809.7 5808.1 P 1 6430 5808.6 5805.5 RB 2 6265 5807.3 5807.8 RE 2 6117 5806.5 5805.3 P 2 6067 5805.6 5801.3 RB 3 5940 5808.5 5805.0 RE 3 5830 5804.4 5803.2 P 3 5780 5803.3 5800.0 RB 4 5555 5801.2 5801.7 RE 4 5408 5800.1 5800.0 P 4 5358 5800.9 5799.2 End 5100 5801.0 5800.0 Notes: 1. Minor deviations in the as built profile occurred from the design plan between Stations 5408 (RE 4) to 5100 (End) as excavation was limited by bedrock. 4
Table 2. Cross Section Survey 1 Cross Section 1 Pin Elev= 5805.41 Pre Construction Dec 13 (XS 1) As Built Feb 14 Dist (ft) Elev (ft) Dist (ft) Elev (ft) 0 5805.1 0 5805.1 0.8 5804.0 10 5804.0 5.9 5802.2 20 5802.0 14.3 5801.0 30 5801.1 18.8 5800.4 40 5799.2 27.9 5800.9 52 5799.2 35.3 5801.3 57 5802.2 48.5 5801.7 57.3 5803.2 Notes: 5
Table 3. Cross Section Survey 2 Cross Section 2 Pin Elev= 5810.23 Pre Construction Dec 13 (XS 2) As Built Feb 14 Dist (ft) Elev (ft) Dist (ft) Elev (ft) 0 5810.4 0 5809.6 1 5809.3 4 5808.4 13.2 5807.5 6 5806.8 28 5806.3 12 5806.6 42 5808.7 17 5804.2 54.3 5806.2 20 5803.4 64.6 5806.6 24 5802.8 67 5807.0 30 5805.2 69 5808.4 38 5806.0 75 5809.0 44 5807.5 58 5807.9 69 5808.1 75 5809.3 Notes: 6
Cross Section 3 Pin Elev= 5811.82 Pre Construction Dec 13 ` (XS 3) As Built Feb 14 Dist (ft) Elev (ft) Dist (ft) Elev (ft) 0 5812.8 0 5811.4 2 5809.9 10 5811.0 13.8 5808.7 19 5809.6 25 5808.1 22 5808.4 41.8 5808.6 27 5808.3 54.3 5809.0 30 5808.5 57.6 5809.4 34 5807.5 75 5810.8 40 5806.9 46 5806.8 50 5806.9 54 5807.0 56 5807.5 60 5808.3 68 5808.6 73 5808.5 75 5809.6 Notes: 7
Table 5. Cross Section Survey 4 Cross Section 4 (XS 4) Pin Elev= 5815.36 Pre Contruction Dec 13 As Built Feb 14 Dist (ft) Elev (ft) Dist (ft) Elev (ft) 0 5814.9 0 5814.9 9.9 5813.3 6 5813.1 11.6 5811.6 9 5811.8 21 5810.6 18 5811.0 32.6 5809.9 25 5809.7 45.6 5810.6 33 5809.7 56.8 5810.8 38 5809.4 65.1 5811.9 43 5809.8 66.8 5813.0 51 5811.4 73.6 5813.9 63 5812.1 66 5813.1 75 5814.1 Notes: 1. Minor deviations in the as built crosssection shape occurred from design as excavation was limited by bedrock. 8
Photo Comparison of Pre construction (Left Column 2 10 14) and As built Conditions (Right Column 2 21 14) from Permanent Photo Points. Refer to Figure 1 for Photo Point Locations and Features. Photo Point 1. Looking north downstream. Wide and shallow channel present during low flow. Pre Photo Point 1. Looking north downstream at RB1. Constructed point bars and defined, deeper low flow channel is evident. Post Photo Point 2. Looking south upstream. Channel lacks any aquatic habitat variety and useable deeper water during low flow periods. Pre. Photo Point 2. Looking south upstream at RE1. Constructed point pars and fast moving riffle is evident. Post. Photo Point 2. Looking north downstream. Photo Point 2. Looking north downstream G1. Deep slow moving water and boulder clusters. Post 9
Photo Point 3. Looking south upstream. Shallow water with limited useable habitat. Pre. Photo Point 3. Looking south upstream at G1 and P1. Deep slow moving water and boulder clusters. Post. Photo Point 3. Looking north downstream. Shallow water with limited useable habitat. Pre. Photo Point 3. Looking north downstream at RB2 and RE2. Cobble point bars create a more defined low flow channel and deeper water depths in riffle sections. Post Photo Point 4. Looking south upstream. Continuous riffle with limited water depth and habitat variety. Pre Photo Point 4. Looking south upstream at P2 and RE2. Riffle flows into pool providing varying habitats and critical deep overwintering holding water. Post 10
Photo Point 4. Looking north downstream. Channel is wide and water depth limiting during winter low flows. Pre. Photo Point 4. Looking north downstream at P2, G2 and RB3. Deeper slower water and boulder habitat clusters. Critical deep overwintering holding water present. Post Photo Point 5. Looking south upstream. Pre. Photo Point 5. Looking south upstream at G2. Post. Photo Point 5. Looking north downstream. Pre. Photo Point 5. Looking north downstream at RB3 and RE3. Cobble point bars create a more defined low flow path and habitat variety. Post. 11
Photo Point 6. Looking south upstream. Pre. Photo Point 6. Looking south upstream at RE3 and RB3. Post Photo Point 6. Looking north downstream. Pre. Photo Point 6. Looking north downstream at G3. Deeper slower water and boulder habitat clusters. Post Photo Point 7. Looking south upstream. Pre. Photo Point 7. Looking south upstream at G3, P3 and RE3. Deeper slower water and boulder habitat clusters. Post. 12
Photo Point 7. Looking north downstream. Pre. Photo Point 7. Looking north downstream at RB4 and RE4. Post. Photo Point 8. Looking south upstream. Pre. Photo Point 8. Looking south upstream at RE4 and RB4. Post. Photo Point 8. Looking north upstream. Pre. Photo Point 8. Looking north upstream at G4. Slower deeper water and boulder habitat clusters. Post 13
iv. Maps Figure 1. 2014 Monitoring Map As Built 14
v. Conclusions Ecological Resource Consultants, Inc. (ERC) has prepared this 2014 As built Mitigation Monitoring Report on behalf of the permittee, City of Montrose, per special conditions specified in USACE Permit (SPK 2013 00851). This is the first of three anticipated annual monitoring reports. This monitoring report provides an evaluation of condition and performance standards for the Uncompahgre River aquatic habitat improvements specifically intended as compensatory mitigation for the whitewater park. Construction of the mitigation commenced on 2/10/14 and was completed on 2/21/14. Work generally progressed from upstream to downstream through each section. The main channel was rough cut and general channel formed. No significant deviations from the design plan were made during the construction activities. All created features are shown on the enclosed 2014 Monitoring Map (Figure 1). The compensatory mitigation has been completed prior to construction of the whitewater park, which is slated for the fall of 2014. Notes: Notification of project initiate was provided to CPW and USACE via email on 2/7/14. Minor deviations in the as built profile (elevations) and cross section shape occurred from the design plan between Stations 5408 (RE 4) to 5100 (End) as excavation was limited by bedrock. A project close out site tour was conducted with the City of Montrose and CPW. Eric Gardunio, CPW Area Aquatic Biologist provided an email (attached) stating the project appears to meet the design criteria and goals. Only the northern river access was utilized for construction. The southern river access was not required and therefore no wetland impacts occurred. All access and staging areas were reclaimed, soils loosened, raked smooth, seeded with a native seed mix and covered with erosion control blanket and coir logs. Parameter 1: Channel Profile Results Results of the 2014 as built channel profile survey compared to the pre project channel profile are presented in Graph 1 and Table 1. The channel profile has been altered to form distinct varying slopes creating the primary habitat features of riffles, pools and glides. The as built condition has been implemented per plan and will be evaluated and compared in the future for significant changes. Parameter 2: Channel Cross section Results Results of the 2014 as built channel cross section survey compared to the pre project channel cross section profile are presented in Graph 2 5 and Table 2 5. The channel cross section has been altered along the entire project reach to form a new distinct crosssection. The as built condition has been implemented per plan and will be evaluated and compared in the future for significant changes. Parameter 3: Visual Observation and Photo Documentation Results Photos from eight (8) permanent photo locations are provided herein along with general notes and comments. The as built condition has notably altered the physical characteristics of the channel per plan. Currently under low flow condition a variety of habitat including fast moving riffles, deep slower pools and glides as well as available instream cover is present. Trout were observed (and caught by anglers) within the improved section immediately upon completion. 15
Please let us know if you have any questions or require additional information at this time. This report has been prepared by: Ecological Resource Consultants, Inc. David J. Blauch, V.P., Senior Ecologist Troy Thompson, President, Sr. Water Resource Engineer CC: Scott Murphy, City of Montrose Eric Gardunio, CPW Area Aquatic Biologist Attachments CPW email correspondence 16
Attachment CPW Email Correspondence 17