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Source: https://erdc-library.erdc.dren.mil/jspui/ A I :75-scale undistorted hydraulic model was used to determine wave conditions at the entrance to Noyo River and Harbor as a result of an offshore breakwater. The impact of the improvements on long-period wave conditions in the harbor as well as wave induced and riverine bed-load sediment patterns was evaluated. The model reproduced the river from its mouth to a point approximately 15,000 ft upstream, both Noyo Harbor and Dolphin Marina located on the south bank, approximately 3,400 ft of the California shoreline on each side of the river mouth, Noyo Cove, and sufficient offshore area in the Pacific Ocean to permit generation of the required test waves. A 45-ft long wave generator, crushed coal sediment tracer material, and an automated data acquisition and control system were utilized in model operation. It was concluded from the model investigation that: (a.) Existing conditions are characterized by rough and turbulent wave conditions in the Noyo River entrance. Maximum wave heights ranged from 8.5 to 13.7 ft in the entrance for operational conditions (incident waves with heights of 14 ft or Jess) and from 12.2 to 15.2 ft for extreme conditions (waves up to 32ft in height) depending on incident wave direction. (b.) The offshore breakwater plan will result in maximum wave heights ranging from 6.3 to 9.3 ft in the entrance for operational wave conditions and 8. 7 to 14.6 ft for extreme conditions depending on incident wave direction. (c.) The offshore breakwater plan will not meet the 6.0-ft wave height criterion in the entrance for all incident waves of 14 ft or less (operational conditions). Based on hindcast data, however, the breakwater plan will result in the criterion being achieved 37 percent more of the time than it currently is for existing conditions when operational waves are present. The magnitude of wave heights also will be decreased by about 27 percent as a result of the offshore breakwater for operational waves. (d.) With no waves present, the offshore breakwater resulted in riverine sediment patterns similar to those obtained for existing conditions except for the 1 00-year (41,000-cfs) discharge. For this condition, the breakwater prevented material from moving as far seaward in the cove as it did for existing conditions. (e.) With waves present from west-northwest and west, the offshore breakwater slightly changes the paths of riverine sediment migration and subsequent deposits for some river discharges and does not for others. In general, considering all test conditions, riverine sediment will deposit in an area in the cove between the existing jettied entrance and the proposed structure location, both with and without the breakwater installed. (f.) The offshore breakwater will not interfere with the migration of wave-induced sediment into the cove for waves from northwest; however, for waves from southwest, the breakwater will prevent some sediment from penetrating as deeply shoreward in the cove as it did under existing conditions. (g.) The offshore breakwater plan will have no adverse impact on surge conditions due to long-period wave energy in Noyo Harbor, Dolphin Marina, and the lower reaches of the river.

Source: https://erdc-library.erdc.dren.mil/jspui/ Two numerical models and two physical models were used to investigate the effects of proposed improvement plans with respect to shoreline erosion at Buhne Point, Humboldt Bay, California. Initially, a numerical tidal circulation model was used to determine the tidal current field adjacent to Buhne Point. Maximum flood and ebb tidal currents were identified and used as test conditions for the physical models. A 1:100-scale physical model of central Humboldt Bay included the jettied entrance to the bay, approximately 18,000 lin. ft of shoreline inside the bay (including Buhne Point), and underwater contours throughout the central portion of the bay and the area between the jetties . This model was used to determine the wave climate (angle of wave fronts and wave heights along these fronts) in the vicinity of Buhne Point for a series of incident wave conditions and directions (waves propagated through the Humboldt Bay entrance) and for various water levels and tidal flow conditions. A 30-ft-long wave generator, an Automated Data Acquisition and Control System (ADACS), and a model circulation system were utilized in model operation. The output conditions obtained from the 1:100-scale physical model were input lnto a 1:50-scale physical model of Buhne Point where the effectiveness of various structures proposed for shore protection was evaluated. This model reproduced approximately 9,200 lin. ft of shoreline in the Buhne Point area and the immediate underwater contours in Humboldt Bay and utilized an 85-ft-long curved wave generator, a model circulation system, and crushed coal tracer material in model operation. Through the use of a numerical sediment transport model of Humboldt Bay, the effects of the optimum improvement plan developed from the 1:50-scale physical model on conditions (sediment movement, tidal flushing, etc.) in other areas in the bay (areas not included in the physical models) were determined. The numerical tidal circulation model provided the tidal current field adjacent to Buhne Point for existing (1983) conditions and for the optimum improvement plan (Plan 30) . Based on the results of this model investigation, it was concluded that changes in tidal current velocities and flow patterns will be minimal due to the proposed improvements. The 1:100-scale physical model of central Humboldt Bay provided the wave front and wave heights along the front in the vicinity of Buhne Point for test waves for five water levels and from three directions. Based on the results of this model investigation, it was concluded that: (A.) Regardless of the direction of incident wave approach from the Pacific Ocean, the angle of the wave front in the vicinity of Buhne Point remains essentially the same. (B.) Test waves from northwest (approaching through the Humboldt Bay jettied entrance almost directly up the axis of the channel) result in significantly larger wave heights in the vicinity of Buhne Point, as opposed to test waves from north and/or west. The 1:50- scale physical model of Buhne Point was used to determine the cliuses of erosion at the point and the effectiveness of various structures proposed for shore protection. Based on the results of thls model investigation it was concluded that : (A.) Wave energy approaching Buhne Point from the jettied entrance to Humboldt Bay resulted tn erosion of the original spit. Sediment eroded from the eastern portion of the shoal and migrated westerly where it entered the navigation channel. (B.) For the originally proposed improvement plan (Plan 1), erosion occurred at the eastern portion of the fill with accretion against the proposed groin. Eventually, material migrated around the groin head and toward the nlivigation channel. (C ). For the proposed groin plan (Plan 2), the shoreline did not remain stable. Sediment eroded at the eastern portion of the fill and accreted against the originally proposed westernmost groin. Material eventually migrated around the groin head and toward the navigation channel. (D.) Sediment eroded in the lee of the shore-connected breakwater with the +7 ft elevatlon (Plan 3) for normal high-tide conditions (water el +6.7 ft). (E.) Sediment remained stable in the lee of the shore-connected breakwater with the +10 ft elevatlon (Plan 3A) for normal tide conditions (water el +6.7 ft), but erosion occurred for extreme hightide conditions (water el +9.5 ft). (F.) Sediment remained stable in the lee of the shore-connected breakwater with the +13 ft elevation (Plans 3C and 3D) for all tide conditions (inclurling the extreme +9.5 ft conditions). (G.) A reverse curve in the shore-connected breakwater where it originates from the existing Buhne Drive revetment (Plan 3D) minimized wave convergence and runup in this area. (H.) A 25-ft-wide fill (el +12 ft) in the lee of the shore-connected breakwater lind adjacent to the existing Buhne Drive revetment (Plan 30) prevented transmitted wave energy from running up on Buhne Drive for all test conditions. (I.) Erosion occurred in the lee of the offshore breakwater plans with the +13 ft elevation (Plans 4 and 4A) for extreme high-water conditions (water el +9.5 ft). When the fill was depleted, wave energy transmitted through the revetment adjacent to Buhne Drive and onto the roadway. (J.) A 1,000-ft-long offshore breakwater with the eastern 425-ft portion installed at a crest elevation of +16 ft (Plan 4B) was required to stabilize the fill in the lee of the structure. Slight erosion of the fill at its eastern limit occurred prior to stabilization, but wave runup onto Buhne Drive did not occur. (K.) A 1,200-ft-long offshore breakwater with the eastern 625-ft portion installed at a crest elevation of +16 ft (Plan 4F) resulted in a stable shoreline in the lee of the structure with no erosion. (L.) Sediment stabilized and remained in the area between the structures with the 425- ft-long extension of the original groin for all test waves, tidal currents, and water levels. (M.) Small amounts of sediment penetrated through the voids of the rubble groin head at the downcoast (western) end of the fill for extreme high-tide conditions (water level +9.5 ft). (N.) Of the improvement plans tested, Plan 3D was regarded as the optimum, considering shore protection and construction costs. The shoreline remained stable for all test waves, tidal flow conditions and water levels. The numerical sediment transport model (CELC3D) provided estimates of sediment movements due to residual tidal currents and wave interactions, for both the existing (1983) conditions and for improvement Plan 3D. From this investigation, it was concluded that no new sediment transport patterns are induced by the optimum improvement plan (Plan 3D). NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ Tests were conducted on a 1:25-scale model of the existing covered channels in the city of Walnut Creek where Las Trampas Creek and San Ramon Creek join to form Walnut Creek. The purpose of the model investigation was to determine the capacity of the existing flood-control channel system and methods for increasing the capacity and improving the flow characteristics in the channels. The model reproduced approximately 818 ft of Walnut Creek, 2,264 ft of San Ramon Creek, and 1,492 ft of Las Trampas Creek , and was constructed so that the slopes of the channels could be adjusted to reproduce various energy gradients that would result from roughness values different than those anticipated. The slopes of the model were initially adjusted to produce an energy gradient resulting from a Manning's roughness factor ? of 0.012 in the prototype. The maximum discharge capacities were determined to be as follows: Las Trampas Creek, 11,000 cfs (100-year frequency flow); San Ramon Creek, 17,400 cfs (2,200 cfs more than the 100-year frequency flow) ; Walnut Creek conduit, 24,000 cfs. A soffit installed on the bottom of the T- beams on the roof of Walnut Creek increased its capacity to 27,500 cfs. The slopes were readjusted to produce an energy gradient for roughness values that varied from 0.012 to 0.014. The maximum discharge capacities for these roughness factors were determined as follows: Las Trampas Creek, 10,000 cfs (1, 000 cfs less than 100- year frequency flow); San Ramon Creek, 17,400 cfs (2, 200 cfs more than the 100-year frequency flow); Walnut Creek conduit, 23,000 cfs. A soffit installed on the bottom of the T-beams on the roof of Walnut Creek increased its capacity to 26,500 cfs. A new transition design in Las Trampas Creek conduit increased the capacity of the conduit to 11,000 cfs.

Source: https://erdc-library.erdc.dren.mil/jspui/ A physical model and a numerical model were used to investigate the design of proposed breakwater configurations for wave protection in the Fisherman's Wharf area, San Francisco Bay, California. A 1:75- scale (undistorted) physical model was used to determine wave conditions 1n the harbor for locally generated short- period wind waves and swell conditions entering through the Golden Gate. The model included the entire Fisherman's Wharf area (Bordered by Pier 45 on the east and Municipal Pier on the west) and underwater contours in San Francisco Bay to a depth of 60 ft. A 40-ft-long wave generator, crushed coal sediment tracer material, and an automated data acquisition and control system were utilized in model operation. A hybrid finite element numerical model capable of calculating forced harbor oscillations for harbors of arbitrary shape and variable depth was used to calculate harbor resonance at Fisherman's Wharf. A numerical finite element grid was used to compute wave-height amplification factors and normalized maximum current velocities associated with the area's response to incident long-period waves ranging from 300 to 600 sec. A ship surge analysis was conducted for the ships moored along or near the Hyde Street Pier. Principal conclusions from the physical model investigation for the 90 plans tested were: (a.) Existing conditions are characterized by very rough and turbulent wave conditions in the various mooring areas of the harbor during periods of storm-wave attack. (b.) For existing conditions, sediment in the Aquatic Park area migrated in both the easterly and westerly directions depending on the angle of wave approach. This movement occurred for only the most severe locally generated storm wave conditions from the various test directions and swell conditions approaching from Golden Gate. (c.) The originally proposed improvement plan with the 1,450-ft-long solid outer breakwater with a 200-ft-wide entrance at Pier 45 (Plan 1) resulted in excessive wave heights in the harbor due to locally generated wave energy entering through the entrance. (d.) Of all the improvement plans tested (Plans 1-90), the 1,560-ft long outer solid breakwater configuration with the cumulative 400-ft segmented breakwater configuration at Pier 45 (Plan 78), was determined to be the optimum plan tested considering wave protection afforded the harbor and entrance, ease of navigation, and economics. The observed long-period wave data analysis and harbor oscillation evaluation for Plan 78 indicated that harbor oscillations did not develop at periods less than 171 sec and the resonant peak of the fundamental mode of oscillation (228-sec period) decreased 15 to 20 percent throughout the inner harbor area. Ship surge motion results indicated that the resonant response of ships in the historic fleet was at periods lower than the fundamental mode of oscillation. The combined results of the physical model study, harbor oscillation study, and ship response analysis for the historic fleet moored along the Hyde Street Pier provide a detailed analysis of short- and long-period wave activity and the resulting predicted ship response changes. In summary, Plan 78 was determined to be the optimum plan tested for short-period wave protection and did not result in significantly changed long-period harbor oscillation or ship mooring conditions. NOTE: This file is large. Allow your browser several minutes to download the file.

Source: https://erdc-library.erdc.dren.mil/jspui/ A Hydraulic Model Investigation of the wave-action problems in Mission Bay Harbor was conducted to develop and test several plans of improvement proposed for reducing wave heights within Quivera Basin and Glen Rick Cove to a satisfactory level. The 1:100-scale model, molded in cement mortar, reproduced the portion of the harbor requiring remedial action, and sufficient coastline and offshore bathymetry to permit accurate simulation of storm-wave attack in the area. A 60-ft-long wave machine and electrical wave height measuring and recording apparatus were utilized in model operation. It was concluded that modifying the curved portion of the south bank of the entrance channel to a series of right-angled steps would effectively provide adequate protection to Quivera Basin and Glen Rick Cove during attack by short-period storm waves.

Source: https://erdc-library.erdc.dren.mil/jspui/ This investigation was concerned with the development of an adequate navigation channel through the reach of the Arkansas River from the mouth of the Verdigris River downstream to below the new U. S. Highway 62 Bridge, as part of the Arkansas River multipurpose project. A movable-bed model reproducing about 5.7 miles of the Arkansas River in the Webbers Falls Lock and Dam pool, including the lower reaches of the Verdigris and Grand Rivers, to scales of 1:80 vertical and 1:120 horizontal was used for the study. The purpose of the study was to develop a system of training structures that would reduce or eliminate shoaling at the confluence of the Verdigris and Arkansas Rivers, develop a channel through the navigation span of the new U. S. Highway 62 Bridge, and reduce the need for maintenance dredging in the Muskogee Harbor area, without producing currents that would be troublesome for navigation. Results of the investigation indicated that : Satisfactory navigation conditions will be provided with the plan developed, except that some shoaling might occur at the mouth of the Verdigris River during low Arkansas River flows and little or no flow in the Verdigris River. Development of an adequate channel and the degree of shoaling tendencies are affected to a considerable extent by the high elevation of bedrock and gravel bars in the reach. Shoaling in the Muskogee Harbor area can be expected because of its location with respect to the river channel alignment. Shoaling will depend on the amount of sediment moving out of the Arkansas River above the mouth of the Verdigris River during high flows. There is a natural tendency for the channel downstream of the harbor area to cross toward the right bank and shoal along the sailing line approaching the navigable span of the new U. S. Highway 62 Bridge. With dikes placed in the deep channel along the right bank, a channel of adequate depth will be maintained under most conditions.

Source: https://erdc-library.erdc.dren.mil/jspui/ Lock and Dam No . 14, proposed for construction on the Arkansas River, will provide a navigable pool extending upstream about 20 miles to the Robert S. Kerr Dam. The investigation, concerned with the study of navigation conditions in the approaches to the lock with the proposed design and with the development of modifications required to produce adequate channel depths and to overcome or minimize the effects of any adverse navigation conditions, was conducted on an undistorted, 1:120-scale, semifixed-bed model, reproducing about 3.4 miles of the Arkansas River and adjacent overbank area including Bruce Island and Cherokee Chute and the lock and dam structures. Results indicate that : Because of the location of the lock with respect to the bend upstream, navigation conditions for downbound tows approaching the lock would tend to be difficult and hazardous. Satisfactory navigation conditions can be developed by modification of the existing structures and realignment of the right bank upstream of the lock. Because of the training structures required to develop adequate channel depths and currents satisfactory for navigation, velocities in the reaches just upstream and downstream of the dam will tend to be high during high flows. Velocity of currents affecting navigation in the lower approach can be reduced by excavation of the channel downstream of the spillway. Shoaling in the lower lock approach will be a problem: shoaling might also occur near Wilsons Rock and in the upper approach channel, depending on flow conditions and rate of sediment movement.

Source: https://erdc-library.erdc.dren.mil/jspui/ Tests were conducted on a 1:125-scale model of Crescent City Harbor and sufficient adjacent coastline and offshore bathymetry to permit generation of waves and wave front patterns from all significant directions of wave approach to the harbor. The hydraulic model, equipped with wave-generating and wave-measuring apparatus, was used to determine the optimum length and location of an extension, or extensions, to the existing breakwater system that would reduce to a tolerable level the present adverse effects of storm waves on navigation and mooring conditions in the harbor. It was concluded that (A.) wave action could be reduced to a satisfactory level in the inner harbor basin by installation of a 400-ft-long northwesterly extension of the inner breakwater; and (B.) a 2000-ft extension of the existing outer breakwater to Round Rock, with a 1200-ft-long companion breakwater extending from Whaler Island, would substantially improve navigation and mooring conditions in the harbor.

Source: https://erdc-library.erdc.dren.mil/jspui/ The Robert S. Kerr Lock and Dam, proposed for construction on the Arkansas River about 395 miles above the junction of the Mississippi and White Rivers, will provide a navigable pool for 37 miles upstream to Webbers Falls Lock and Dam. The project comprises a nonnavigable gated dam with eighteen 50-ft-wide by 44-ft-high tainter gates, a 110- by 600-ft lock on the left bank with a maximum lift of 48 ft, and a four-unit powerhouse with a 110,000-kw generating capacity on the right bank. A 1:120-scale, fixed-bed model, reproducing approximately 3.3 miles of the Arkansas River, was used to determine flood stages at the dam, navigation conditions in the lock approaches, and tendencies for sediment deposition in the lower lock approach, and to develop modifications required to provide satisfactory navigation conditions. The investigation has resulted in the development of modifications in the original design required to produce satisfactory navigation conditions in the approaches to the lock. In general, the results have indicated the following : (A.) A fill or dike is required along the left side of the upper lock approach channel to eliminate the adverse effects of currents moving across the approach channel from the overbank toward the spillway. With the fill, navigation conditions near the upper guard wall would be better with some ports in the wall. (B.) Water-surface elevations at the dam embankments can be lowered by excavating the channel approaching the spillway more and by placing spoil along the right overbank. (C.) Flow from the powerhouse with no flow through the spillway produces a large eddy that extends into the lower lock approach. Currents in this eddy would adversely affect upbound tows attempting to approach the lower guard wall. Satisfactory navigation conditions with powerhouse flow can be developed with a dike extending from the end of the lower guard wall. Shoaling of the approach channel can be expected from sediment moving from the area downstream of the spillway and powerhouse. The effect that sediment deposited over the lock-emptying outlet will have on lock-emptying operations depends on the amount of deposition and on the difference in water-surface elevations inside and outside the lock chamber.

Source: https://erdc-library.erdc.dren.mil/jspui/ The spillway for Clarence Cannon Dam, which is to be subjected to discharges as large as 268,000 cfs, was studied on a 1:50-scale comprehensive model to determine flow conditions in the approach and exit channels and performance of various elements of the structure. The withdrawal characteristics of the original design water-quality weir were unsatisfactory and subsequent modifications were developed to obtain the desired withdrawal characteristics without affecting the capacity of the spillway. Simulated pumpback operations indicated that the proposed pumped storage scheme of power generation will not produce any material internal mixing or destratificati on of the reservoir. The right and left abutments were modified to reduce drawdown and improve distribution of flow entering the stilling basin. The baffle piers were relocated to improve energy dissipation in the stilling basin. Stilling basin training wall heights were reduced downstream of the baffle piers without impairing hydraulic jump action or exit channel velocity distribution. Dynamic shear and moment on each of the six monoliths of the divider wall between the stilling basin and powerhouse tailrace were measured by means of electronic force cells. The size and extent of exit channel protection required downstream of the spillway were also determined.