Overflow spillway design online 3. Emergency spillways activate only during emergencies. The upper curve at the crest may be made either larger or sharper than the nappe. The dam crest and spillway crest elevations are 563. A weir is a barrier placed on the path of a stream through which it flows to a lower level. Armour the emergency overflow spillway with riprap in conformance with BMP C209: Outlet Protection. 7 %¡³Å× 1 0 obj >/Metadata 90 0 R >> endobj 4 0 obj >/Shading >>/Pattern>>/XObject>>/ColorSpace>/ExtGState >>>>> endobj 5 0 obj >/Shading >>/Pattern Sep 2, 2011 · The spillway approach height is measured from the bottom of the reservoir to the spillway crest just upstream of the spillway. Storage Volume, Depth and Duration a. 6 %âãÏÓ 335 0 obj > endobj 348 0 obj >/Filter/FlateDecode/ID[7C85A007CDD1E0721BF179D9E969DDEF>]/Index[335 22]/Info 334 0 R/Length 84/Prev 1736076/Root 336 4. Unlike ogee spillways, the design of breast wall spillways has not been standardized. Aug 9, 2021 · PDF | Overflow spillways are essential structures of dam projects, releasing surplus flood water to ensure dam safety. Siphon Spillway 7. An overflow spillway, as presented in fig. Chute Spillway . Overflow (or Ogee) Spillways Overflow spillways are by far the most widely adopted. 4 Auxiliary spillways 3. Online WES spillway design. Chapter 1 of this Design Standard was developed to provide: • An overview of how the Bureau of Reclamation analyzes/designs Jan 2, 2024 · Spillways play an important role in ensuring dam safety and effective water management. . Many dam failures in the past can be attributed to inadequate spillway design. In the UK they may be known as overflow channels. Dipali Examples of culvert spillways include the service spillway at Reclamation’s Martinez Dam (embankment) and the emergency spillway at Reclamation’s Weber Basin Comber Dam (embankment)”. rates. Fig 2. 7 H : 1 V (4) Design discharge = 8000 cumecs (5) Length of spillway = 6 spans with a clear width of 10 m each. Determine the rating curve for a 100-ft wide overflow spillway with a design head of 30 ft. Aug 11, 2022 · Spillway design. 1 Straight drop spillway 2. 2 OVERFLOW SPILLWAY. An overflow spillway is an improvement upon the free overfall spillway. In the United Kingdom, they may be known as overflow channels. Sometimes hiring your second cousin, who owns a bull dozer, to build your pond may not be as cheap as you think! Oct 23, 2024 · The Spillway Which Can Be Called as an Overflow Spillway Is Essentially. The total length Dec 14, 2016 · It then focuses on the design of ogee or overflow spillways. Coefficient of discharge for flow under gates (USBR, 1988) Overflow spillways are named as high-overflow, and low-overflow depending upon to the relative upstream depth P/H D. In this calculation, a weir with a water level h flowing over a threshold with a height P and width b is considered. Head: The vertical distance from the water surface to the crest axis is called the head. 2 Control Structure Design - Gated Spillways 3. Citations: Overflow Spillways The flow depth at the crest is slightly critical than hydrostatic pressure. Sep 6, 2013 · Design of chute and side channel spillways - Criteria: IS 6512 (pdf) IS 6512 (txt) 1984: Criteria for design of solid gravity dams: IS 6934 (pdf) IS 6934 (txt) 1998: Recommendations for hydraulic design of high ogee overflow spillways: IS 7365 (pdf) IS 7365 (txt) 2010: Criteria for hydraulic design of bucket type energy dissipators: IS 7894 Jun 19, 2012 · The difference between side channel and chute spillway is that in chute spillway, the water flows at right angle to the weir crest after spilling over it, whereas in a side channel spillway, the flow of water after spilling over the crest is turned by 90 degrees such that it flows parallel to the weir crest. Here’s the best way to solve it. 21. This course is based on a there is a 18" dia concrete overflow tube in place So was raising the embamkment to have 3' of freeboard making a 15' wide spillway on undisturbed soil in the hillside got some grass to plant but was think of adding another overflow tube where the embamkment burst, which is the natural channel , I can get abs tubes in 12, 18 and 24" dia Sep 26, 2022 · Embankment overflow stepped spillways have common features with stepped storm water systems and sabo channel systems (Photo No. The main purposes of spillways are to safely release surplus water from the reservoir and regulate floods. 2 of "Open-channel Hydraulics," by V. The flow remains in contact with the spillways surface (except for possible aeration ramps) from the crest of the dam to the vicinity of its base. It is easier and cheaper to plan and design a spillway than fix one. j. Best Practices Resources. 8-ft-high (10-m) with tread H = Upstream energy head above the spillway crest. Fantina, PE 271. Here are some of the different types you may see: Overflow spillways Mar 2, 2015 · Design of spillway Design an ogee spillway for concrete gravity dam, for the following data : (1) Average river bed level = 100. I n addition to the above overflow provisions, ponds shall have an emergency overflow spillway. 05 10 TITTTITIITIT 15 20 25 £ He? range of 0. It provides example designs for overflow spillways and calculations for determining spillway length. EM 1110-2-3600, Management of Water Control Systems. 0 m (2) R. (b) Overflow spillway with downstream flip bucket (Reece dam TAS, 1986) (courtesy of Hydro-Electric Commission Tasmania). 3 Examples of spillway design: (a) Overflow spillway with downstream stilling basin (Salado 10 Auxiliary spillway) (courtesy of USDA natural resources conservation service), (b) Overflow spillway with downstream flip bucket (Reece dam TAS, 1986) (courtesy of Hydro-Electric Commission Tasmania). Service Spillway Design 3. Ensuring the spillway is correctly sized for the pond and local climate conditions is critical to prevent this. EM 1110-2-1612, Ice Engineering. docx - SSCAFCA Feb 18, 2020 · Again, the design of your lake's overflow pipe and spillway, to meet the needs of your lake and water shed, plays an important part of your lake's recreational fishing success. EM 1110-2-1602, Hydraulic Design of Reservoir Outlet Works. The essential Coupanec & Kamal El kadi Abderrezzak (2021) Surrogate-based optimization for overflow spillway design, LHB, 107:1, 1-11, DOI: 10. Sep 17, 2017 · It then focuses on the design of ogee or overflow spillways. The WES shapes follow the equation: X n = K H d n-1 Y, in which X and Y are the coordinates of the crest profile, with the origin of coordinates at the highest point of the crest; H d is the design head excluding the velocity head of the approach flow; K and Hydraulic design of dams and weirs (1) An overflow spillway is to be designed with an un-gated broad-crest followed by a stepped chute and a hydraulic jump dissipator. designed to accommodate the probable maximum flood. In the case of hi_gh overflow spillways the velocity of approach head may be considered negligible. less than 30 deg. Determine the crest elevation of a WES spillway section having a vertical upstream face, with the following hydraulic and geometric data: Fig. How my farm pond is filled from the creed and overflow is returned to the creek. 17 Design of overflow spillway. Energy Dissipater Design • Spillway design guide • Guide to spillway failure mechanisms • Spillway examination guide • Reservoir owner and operator guidance: spillways . 0 and 539. The profile is made such that the shape of the lower nappe of a freely falling jet over a duly ventilated sharp-crested weir. ) and the step height ranges from about 0. They are mainly used on masonry or concrete dams, and if used with earthfill need a separate concrete structure. 1 Uncontrolled Spillways 3. The spillway design flood (SDF) is a function of social, moral and Hydraulic design criteria: Sheets 111-1 to 111-2/1, overflow spillway crest: Date published: 1977-01: Notes: Revised 9-70: File size: 31558491 Bytes: Document location: 15994401_volume1. L. 30. 3, can be gated or ungated, and it normally provides for flow over a gravity dam section. Such features are most important in preventing overflow at the spillway, thereby stopping upward migration of g. If the crest of the spillway is ogee shaped, the weir coefficient will be automatically adjusted when the upstream energy head is higher or lower than a user specified design head. Sep 1, 2015 · Spillway of the Robert Bourassa dam in Quebec, Canada. Devote good money to better spillway design and construction, rather than the outlet pipe structure. Overflow Spillways The flow depth at the crest is slightly critical than hydrostatic pressure. 6 Access Nov 6, 2018 · This thesis covers the master diploma work conducted at Hohai University, Nanjing, People's Republic of China. Graphs present sample rating curve data. It is located at the right abutment of the dam. Mar 16, 2018 · Ogee spillway is also known as the overflow spillway and as the name suggests, water overflows from the top and so the crest is so designed that it retains the hydraulic stability and also at the bottom a curve is provided which helps in dissipating the excess energy. , the 100-year storm, 500-year storm). 33. Construction of a small overflow spillway Completed spillway blocks A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. s. For gravity dams, it is generally located within the dam body. Purpose This document aims to provide nationally recognised guidance on the main design principles, methods and current best practice for the design of new spillways, and The beehive grate overflow structure as shown in Figure 4 - 73: Overflow Structure may also be used as a secondary inlet. Where an emergency overflow spillway would discharge to a slope steeper than 15%, consideration should be given to providing an emergency overflow structure in addition to the spillway. The design, efficiency, and maintenance of these structures are important in averting catastrophic failures and ensuring the controlled release of surplus water. of spillway crest =204. The computation procedures follow Section 9. Design aspects for spillway crest gates like radial and drum gates are covered. 17. The document discusses the design of overflow structures for dams. In this article, we have focused on various types of spillways and design methods. Available from 17. Figure 11 shows a typical discharging capacity curve. 9), which differ significantly from concrete dam stepped spillways. 65mOD. Shaft Spillway Microsoft Word - CHAPTER 22 DPM 3-29-2010. August 2021 This article throws light upon the eight most common types of spillways. Tables provide values for variables used in spillway design equations over a range of slope ratios. Emergency overflow spillways control the location of stormwater facility overtopping and direct overflow to the downstream conveyance system or other acceptable location. edu. Figure 1 : Chief Joseph Dam overflow spillway. 3 Head The head is the distance measured vertically from the %PDF-1. Design Standards No. Pond Bottoms and Side Slopes HYDRAULIC DESIGN OF STEPPED SPILL WAYS Overflow conditions occur on spillways during regular periods of release or during emergency flood events. Fig. e. OGEE OR OVERFLOW SPILLWAYS Definition sketch of overflow spillway cross-section. The chute slope spillway crest measured from the river bed to the design head is greater~than and equal to or less than 1. Shaft spillway is used when the possibility of overflow spillway and through spillway has been ruled out because of non-availability of space due to topography. and the design head above crest level will be 2. This type of spillway is usually used in conjunction with an earth- or rock-filled dam; however, concrete gravity dams also employ chute spillways. 1 shows a typical layout. In the example shown in the figure above there are 15 identical gate openings and the entire top of the embankment is specified as an overflow weir. It is theoretically the energy level above the spillway crest that the spillway was designed for. 0448 T 046 044 H fl. Spillways are provided for all dams as a safety measure against overtopping and the consequent damages and failure. 2 Design Criteria May 28, 2019 · The smaller one is called the principal or service spillway that passes normal inflows when the reservoir is full. It also discusses the advantages and disadvantages of using gates, and common types of gates like hinged flap gates, vertical lift gates, and radial gates. Available from Dec 20, 2019 · The spillway is often the most expensive component of a dam and, from a safety point of view, one of the most critical design aspects. M. Nevertheless, some concrete dams also use chute spillways. Therefore, a recourse is taken to study the existing structures, while designing a new project. The hydraulic characteristics are defined as follows: Determine A labyrinth spillway is an overflow weir folded in plan view to provide a longer total effective length for a given overall spillway width. Siphon Spillway. 2 Control Structure 3. Overflow spillways Controlled (gated, guided) Uncontrolled (ungated, free) Almost all recently constructed dams are installed with crest gates to store more water in the reservoir. 95. Design Chart 2. Formula: X n = K H d n-1 Y. The flow remains in contact with the spillways surface (except for The Preliminary Design . The user can specify either a broad crested, ogee, or sharp crested weir shape for the spillway crest of the gate. Surrogate-based optimization for overflow spillway design. Bazin (1898)’s studies are often cited as preliminary works in the design of straight-crested spillways. Side Channel Spillway 4. They are mainly used on masonry or concrete dams, and if used with earth fill and need a separate concrete structure. 1080/27678490. The document emphasizes that the design discharge and overflow May 23, 2021 · It describes overflow or ogee spillways, chute spillways, and other spillway types. Design Considerations 1. Jul 19, 2019 · No special design required foe inlet of small height but for large height, a flat inlet is often used. Sep 20, 2024 · Undersized Spillways: If a spillway is not designed to handle the maximum expected water flow, it can become overwhelmed during heavy rainfall, leading to overflow and possible damage to the pond and surrounding areas. g. Tilted outlet type of Siphon Spillway. Existing spillway overflow The spillway consisted of a 11. See full list on web. 33 respectively. Type # 1. Spillways ensure that water does not damage parts of the structure not designed to convey water. Design discharge Q, in m [or ft] Thank you for running online_WES_spillway Please call again. It consists of a vertical riser that controls basin water levels and an outlet pipe. Design the Emergency Overflow Spillway per A600 - Emergency Overflow Spillway. DESIGN OF SPILLWAYS A reservoir will overflow if its capacity is less than the difference between the volumes of inflow and outflow. These are usually gated or ungated and allow water to overflow if it builds up behind the dam. Includes emergency spillway design details Feb 15, 2023 · Sediment basins consist of a principal spillway, dewatering device, and an emergency (overflow) spillway. 1. An overflow spillway can be gated or ungated, and it normally provides for flow over a gravity dam section. tr Aug 9, 2021 · The design of overflow spillways must be optimised with respect to hydraulic performance, dam safety requirements and economic cost. 1 Description. i. 2 OVERFLOW SPILLWAY An overflow spillway can be gated or ungated, and it normally provides for flow over a gravity dam section. The energy dissipation arrangement of the spillway consists of the Low spillways have appreciable approach velocity, which affects both the shape of the crest and the discharge coefficients. 1 Entrance Channel 3. 14: Appurtenant Structures for Dams (Ch. The crest level will be at 70. Shaft (or Morning Glory) Spillway 6. h. A section on design of spillways that considers cavitation and Guidelines for Hydraulic Design of Stepped Spillways A SunCam online continuing education course Spillway Design for Small Dams by David E. May 27, 2017 · Free Overfall Spillway Ogee-shaped Spillway: An Ogee-shaped (or Overflow) Spill way is the most commonly used spillway. It is widely used with gravity dams, arch dams & buttress dams. OGEE OR OVERFLOW SPILLWAYS 0. The ogee or overflow Jan 20, 2020 · Uncontrolled overflow spillways are the most reliable choice, but only at the cost of wasting a considerable amount of water. Spillway erosion protection on the downstream Embankment overflow stepped spillways have common features with stepped storm water systems and sabo channel systems (Photo No. A spillway is designed to prevent overtopping of a dam at a place that is not designed for overflow. pdf: Contributed by: Humphreys Engineer Center Support Activity, Library: Record number: RN 735-17c: Disposition: Temporary, destroy when no longer needed. During extreme events, overtopping of the entire crest of the dam may occur and the downstream face is exposed to erosive flow conditions Jul 15, 2024 · It consists of an ogee-crested overflow spillway with seven radial gates, each 15 m wide and 21 m high. Table 1. The spillway design capacity is about 25,360 m 3 /s (240 m 3 /s/m) with a design head of 17. 2021. Design Head: The value of the head for which the Ogge spillway is designed. 1. The document also discusses intake and outlet works for reservoirs, including their components and functions. Principal function of a spillway is to pass down the surplus water from the reservoir into the downstream river. 0 a. 6. They are used, when a reservoir is full, to pass floodwater safely, and in a controlled way, over a dam, around it or through it. Construction of a small overflow spillway Completed spillway blocks overflow through an overflow spillway or riser set at an elevation related to the WQV. Energy dissipaters, like stilling basins, are structures that reduce the high kinetic energy of water flowing from spillways to prevent erosion. g. Ogee spillway is also called as overflow spillway and is an improvement over straight drop spillway. An essential preliminary to the hydraulic design of a spillway is a hydrological analysis to determine the design flood . f T 042 off 038 0 Q= C, Vag LU, & DX Y. Spillways A spillways is a structure constructed a or near the dam site to dispose of surplus water from the reservoir to the channel downstream. An overflow spillway is an improvement upon the free over fall spillway. An overflow spillway section fitted for the Longtan Dam was designed and the loads The document describes a program that helps with the hydraulic design of surface spillways and related structures. Spillways have a tendency to erode, wash out, get perforated by digging burrowing animals. Spillways frequently have a cross section known as an ogee, which closely approximates the underside of a nappe from a sharpcrested weir. A labyrinth spillway has advantages compared to the straight overflow weir and the standard ogee crest. An overflow spillway is typically used with concrete gravity dams. It describes different types of overflow structures including frontal, side-channel, and shaft overflows. This Special Issue (2) Ogee - Shaped (or Overflow) Spillway. 1935003 Spillways are structures that either form part of a dam, or are found just beside one. This editorial presents a brief overview of the eleven papers in this Special Issue, Advances in Spillway Hydraulics: From Theory to Practice, and frames them in current research trends. Dec 24, 2019 · The overflow spillway is either gated or ungated and is an integral part of the concrete dam structure. (c) Stepped spillway chute (Loyalty Road Low Overfall Spillway: The ratio of their height (P) measured from the river bed to the design head (H d) is less than or equal to 1. Design spillway capacity: 4740 m 3 /s, overflow event: 365 m 3 /s. The overflow criteria for single-purpose (treatment only, not combined with flow control) wetponds are as follows: Jun 7, 2023 · Over the past decades, significant advances have been achieved in hydraulic structures for dams, namely in water release structures such as spillway weirs, chutes, and energy dissipators. 2. The hydraulic characteristics are defined as follows: 1. Often an overflow or trickle tube is incorporated with the installation of the drainpipe. 4 Dis charge Capacity of the Spillway. Consult a qualified lake design engineer before building. For technical guidance on designing effective overflow spillways, refer to the United States Bureau of Reclamation’s Design of Small Dams. Apr 8, 2022 · Subject - Water Resource Engineering - IIVideo Name - Ogee Spillway and Its Design PrinciplesChapter - Spillway and Flood Control WorksFaculty - Prof. 5. Common spillway types include overflow, which guides water smoothly over a curved crest; side channel, which diverts flow through a parallel channel; and tunnel, which Examples of spillway design: (a) Overflow spillway with downstream stilling basin (Salado 10 Auxiliary spillway). m. 6 A600 - Emergency Overflow Spillway. Ogee (Overflow) Spillway 3. Tunnel (Conduit) Spillway. pdf Whenever there is surplus water, it will be freely disposed of through ogee spillway along its ogee shaped crest hence it can also be called as an overflow spillway. l. A dam’s spillway (overflow spillway) is designed for a capacity based on the dam’s inflow hydrograph, turbine capacity, and storage capacity. 3 Discharge Carrier Design 3. A design procedure for overflow spillway crests, which is applicable to a wide range of approach depths, upstream slopes, and heads on the crest, is developed. 3: General Spillway Design Considerations), USBR. 75 to 0. Design of the Ogge Spillway. A spillways acts as a safety valve for the dam, because as soon as the water level in the reservoir rises above a predetermined level Aug 20, 2013 · It describes different types of spillways like overflow, trough, siphon, and side channel spillways. 0 m R. The types are: 1. 63m flat crested weir, with a crest level at 144. Design Standard 14 is a new document. Namely the channel has often a trapezoidal cross-section, the bed slope is moderate (i. The first hydrodynamic geometries for spillways were proposed by Müller Weir Spillway. 4. 19. 2. The highest invert of the outlet pipe sets the WQ design water surface elevation. An Ogee-shaped Spillway has a control weir of ogee-shaped, which Dec 14, 2018 · Main spillways are designed to pass the entire design flood volume, while auxiliary spillways supplement the main spillway. It discusses spillway crest profiles, discharge characteristics including effects of approach depth, upstream slope, and submergence. Ponce (2014). Free Over-Fall (Straight Drop) Spillway 2. In this study, the ogee-crested spillway’s or overflow spillways discussed in this paper. Cascade Spillway 8. b. It contains sheets with information on topics like crest geometry, rating curves, discharge calculations, and hydraulics of channels and basins. Excavated from rock, this unlined channel is almost 3280 ft (1 km) in total length, there are 10 steps each 32. The essential %PDF-1. 4 Jul 28, 2022 · Overflow spillways are often referred to as emergency spillways because they are designed for extreme precipitation events (e. Many types of spillways can be considered with respect to cost, topographic conditions, dam height, foundation geology, and hydrology. 7 overflow Spillways Overflow spillways from settling ponds need to be carefully designed and constructed to avoid erosion or washouts froffi the pond discharge. Several Earth & Rock fill dams are also provided with this type of spillway as a superstructure. This weir discharged into a concrete channel that transitioned to a steep 4m wide stepped spillway channel with masonry side walls. 3 Resilient and Flexible Discharge Channel Linings 4. Jul 11, 2018 · (emergency) or overflow spillway; replacing pipe or in any other way altering a principal spillway; making any repairs of erosion or undermining associated with seepage through the dam; building a roadway on or across any part of a dam; burying pipelines; or in any way altering the approved operational features of a dam. The crest is at elevation 1200 ft and the river bed upstream from the spillway is at elevation 1110 ft. Explanation: Ogee spillway is an improvement over free overflow spillway and is widely used with concrete, arch and buttress dam. Gated Spillways within HEC-RAS can be modeled as radial gates (often called tainter gates), vertical lift gates (sluice gates), overflow gates (open to the air or closed top), or a family of user the hydraulic process and design of overflow spillways relies generally on laboratory studies and, to a limited extent, on numerical modelling. The width of the crest, chute and dissipation basin will be 75-m. 3. In high-overflow spillways, this ratio is (P/H D >1. Next time you visit a dam, look for its spillway. 4 teristics of the overflow spillway and slide-gate-controlled outlet works Spillway Design for Small Dams Introduction: This course presents an overview of the features that go into the design of spillways for small dams. An earlier crest design procedure is used to proportion a series of models covering a wide Size the pond outlet pipe, at a minimum, to pass the online WQ design flow. The overflow event used in the design of the weir must be consistent with the intensity, duration, and frequency of the rainfall event used in the roadway Fig. Dec 28, 2021 · Overflow Spillway. Construction of a small overflow spillway Completed spillway blocks Outlet structures may be of the overflow spillway type or may consist of a culvert pipe with riser, as described below. 5 Overflow (or Ogee) Spillways Overflow spillways are by far the most widely adopted. 63 m. In this spillway, the water jet falls clearly away from the face of the spillway and the gap between the jet and the face is kept ventilated. 1 WES standard spillway shapes. Depending on the design, the auxiliary spillway may only flow for a few scary moments in a dam’s entire lifetime. Hydraulic Design Criteria (HDC) sheets and charts. The overflow type spillway has a crest shaped in the form of an ogee or S-shape. 2 OVERFLOW SPILLWAY An overflow spillway can be gated or ungated,and it normally provides for flow over a gravity dam section. k. Chute Spillway A chute spillway is usually constructed for earth or rock-filled dams. 4 m. A principal spillway conveys the design volume of treated stormwater away from the site and discharges it. An emergency outlet or spillway which is capable of conveying the spillway design flood (SDF) should be included in the design. 2 Rock Discharge Carriers 3. Chute (Open Channel or Trough) Spillway 5. . This structure will aid in maintaining a normal lake level and is especially desirable for lakes having a continuous overflow due to springs. Small dams in this course refer to a wide variety of water impoundments that includes detention basins, municipal ponds, agricultural ponds, and others. 393 394 Design of weirs and spillways Fig. Ogee spillways are most commonly used in case of gravity dams, arch dams, buttress dams, etc. The SDF is usually equal to the 100-year design flood 21. Size and Dimensions of the Orifice Spillway and its Disposition with respect to Hence, any discharge higher than the design flood passing through the overflow spillway would try to shoot forward and get detached from the spillway surface, which reduces the efficiency of the spillway due to the presence of negative pressure between the sheet of water and spillway surface. itu. 0 m (3) Slope of d/s face of gravity dam = 0. 1 Concrete Discharge Carriers 3. 15 Ogee or overflow spillway The Ogee spillway is generally provided in rigid dams and forms a part of the main dam itself if sufficient length is available. The design energy head is not measureable, but comes from the spillway design calculations. 20. and chute spillways A section on design of spillways that considers cavitation and aera-tion also is included. And, the other is called the auxiliary or emergency spillway that only engages during extreme events. The objective of this work is to numerically investigate spillway design using a shape optimisation process based on computational fluid dynamics software. [191030 10:55] A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. st. EM 1110-2-1605, Hydraulic Design of Navigation Dams. EM 1110-2-2400, Structural Design of Spillways and Outlet Works. Extended detention basins should be designed to mitigate runoff peak flow . 33) and the approach velocity is generally negligible. 16 Emergency spillway at San Vicente Dam, San Diego County, California. 1 RCC Overtopping Protection Projects. uimrm dlhz dxdu mirn uwq xeifjfecm exn dwnaqdx fqygx gfon lfc ptln rjqsdye daintoqg bqnsk