What is the average peak discharge from a large tectonic basin?
Tectonic and volcanic basins can nearly always be considered ‘large’ basins, and consequently, their peak discharges, where independently estimated, mostly range between 1 and 20 g1/2h5/2 ( O'Connor and Beebee, 2009 ).
What is h in peak outflow discharge?
where Q is the peak outflow discharge, g is gravitational acceleration, and h is the difference between the surface elevation of the impounded waterbody and the bottom of the breach at the outflow point, generally equivalent to the drop in water surface during the course of the outflow event.
What is the peak discharge of a type 2 design storm?
For T = 100 years, the peak discharge given by Equation (18) is 60% greater than the value obtained from conventional calculations using the Type 2 design storm.
Why use QP* to estimate the peak discharge for design storms?
Because the 10-year, 24-hour rainfall distribution provides a good average for all return period design storms, the graphical and mathematical relations for qp* can be used to estimate reliably the peak discharge for any other return period typical in hydrologic design of minor hydraulic structures.
Would you want to put a golf course on a wetland?
Wetlands can be especially useful for golf courses, where they can be incorporated into the drainage and water management design as an attractive alternative to traditional water features.
What are some environmental concerns that arise from the development of golf courses?
The main areas of concern were:Pesticide Use and Its Effect on Ground and Surface Water.Beach Access.Beach Erosion.Coastal Dune and Wetland Loss.
Is golf course runoff a nonpoint source pollution?
Golf courses have the potential to be a nonpoint source of pollution.
Do golf courses drain well?
Drainage is fundamental to golf course architecture. If a course doesn't drain well, it will rarely play well. So figuring out how to move water off fairways and greens is nearly always at the top of an architect's mind.
How can golf courses be more environmentally friendly?
Below are our best tips for creating an eco-friendly golf course.Increase the biodiversity of your golf course.Limit your use of pesticides.Source food from local providers.Reduce water usage.Invest in better waste management.
How do golf courses help the environment?
But golf courses also have great opportunities to make a positive impact. They can provide wildlife sanctuaries, preserve natural areas in urban environments, support native plants and wildlife, protect water resources, rehabilitate degraded landscapes and promote environmentally-positive management to the public.
How can we help lessen or alleviate nonpoint source pollution?
What can citizens do to reduce nonpoint source pollution? Limit use of pesticides and fertilizer and use them at appropriate times of the year in recommended amounts. Introduce natural predators to your garden, and use pest resistant plants. Remove eggs, larvae, cocoons, and adults from plants by hand.
Why does the government not do more to regulate nonpoint source pollution?
Why does the government not do more to regulate nonpoint source pollution? Nonpoint source pollution is difficult to regulate, because its source is difficult to track.
What are some examples of nonpoint source pollution?
Nonpoint source pollution can include:Excess fertilizers, herbicides and insecticides from agricultural lands and residential areas.Oil, grease and toxic chemicals from urban runoff and energy production.Sediment from improperly managed construction sites, crop and forest lands, and eroding streambanks.More items...•
How to reduce runoff?
Reduce the potential for increases in runoff quantity by minimizing impervious surfaces and maximizing infiltration of stormwater runoff. Eliminate curbs where possible and encourage sheet flow from paved areas. If curbing is required, use Cape Cod curbing or other similar curbing, which allows amphibians to climb.
How to encourage infiltration of stormwater?
Encourage infiltration of stormwater through the use of vegetated depressions, swales, rain gardens and bioretention, and other vegetated drainageways to convey and hold stormwater and provide for a slow recharge to groundwater, where soils permit.
What is the purpose of Chapter 5?
Source control practices and pollution prevention ( Chapter Five) are operational practices that can reduce the types of and concentrations of pollutants in stormwater runoff by limiting the generation of pollutants at their source .
What is a comprehensive stormwater management strategy?
A comprehensive stormwater management strategy should prevent or mitigate urban runoff problems and protect beneficial uses of receiving waters in a cost-effective manner. The stormwater management measures described in this manual are designed to accomplish this objective by adhering to the following guiding principles:
How to remove runoff from a site?
The traditional approach to drainage design has been to collect and remove runoff from the site as quickly as possible through the use of curbs, gutters, catch basins, and storm sewers , often resulting in the discharge of polluted runoff directly to receiving waters. While this approach effectively removes runoff from a site, it does not address water quality or downstream flooding and erosion issues. Similarly, the traditional approach to flood control has been to attenuate peak runoff to pre-development levels through the use of detention and retention ponds. While stormwater detention or retention facilities can effectively reduce peak discharge rates, they also typically prolong the duration of elevated flows and do not reduce runoff volumes unless infiltration is incorporated into their design. Historically, these facilities have not adequately addressed problems associated with water quality, runoff volume, and downstream channel erosion.
What are the elements of a stormwater management program?
Effective site planning and design is the most critical and potentially beneficial element of a successful stormwater management program since it addresses the root causes of both stormwater quality and quantity problems early in the development process. Source controls and pollution prevention, as well as construction erosion and sedimentation controls, are also key elements for preventing or mitigating stormwater quality problems. These preventive measures can reduce the size and scope of stormwater treatment and flood control facilities. However, it is also recognized that stormwater treatment and flood control measures are often effective and necessary to achieve water quality and quantity control objectives. Figure 3-1 shows the relationship and recommended hierarchy of these stormwater management elements.
Why are stormwater treatment and flood control measures important?
However, it is also recognized that stormwater treatment and flood control measures are often effective and necessary to achieve water quality and quantity control objectives.
What is peak discharge?
Peak discharge is the maximum rate of flow for a given condition and is used in the design of conservation measures.
What condition increases peak discharge rate?
5. Hydrologic condition - Decreased density of vegetation will normally increase runoff by lowering the interception and infiltration potential. This, in turn, increases the peak discharge rate.
When did NRCS develop runoff curve numbers?
In the 1950's , NRCS perfected its current runoff curve number and hydrograph development concepts for the Public Law 566 watershed program. These new procedures were tested and used by NRCS engineers to develop peak discharges for design of structural measures and to evaluate their downstream effects. These research-based procedures use NRCS soil classification information and can account for changes in watershed characteristics.
How does tillage affect peak discharge?
9. Agricultural practices - Tillage, management, and land treatment practices can affect the amount of runoff contributing to peak discharge. Practices that increase infiltration and surface storage potential, and lengthen flow paths tend to decrease peak discharge. Practices that shorten flow paths usually increase peak discharge. These effects are greater for small storms and may not be significant for major flood producing storms.
When was the NRCS graphic peak discharge method revised?
The NRCS Technical Release No. 55, Chapter 4, Graphical Peak Discharge Method, revised in 1986, was developed for:
How long does it take for a drainage area to pass through a subwatershed?
2. Drainage areas subdivided into homogeneous subwatersheds where the time of concentration does not exceed two hours and the time it takes for flow to pass from the subwatershed outlet to the peak discharge estimate point (travel time) does not exceed three hours.
When were runoff and peak discharge estimates simplified?
Runoff and peak discharge estimates were complicated, but standardized for consistency with parameters based on evaluation of physical data. In the early 1960's, the procedures were simplified for use in the design of conservation and water control practices.
What are the benefits of offsite construction?
An added benefit of offsite building is that it also reduces the cost of labor for your company–further offsetting the rising material costs in construction. Generally, it costs far less to transport partial assemblies from a manufacturing company than to hire workers to move raw resources to a construction site.
How does lean construction reduce waste?
Studies have shown that by using lean construction, companies have the capacity to reduce material waste by approximately 64%. Lean construction also increases employee accountability, resulting in higher quality in the finished project.
Why do construction materials prices fluctuate?
As mentioned, seasonally material prices can fluctuate due to natural disasters and heightened construction activity. One main reason for the annual rise includes an increase in energy and crude oil costs. For example, crude oil, a key component of asphalt, increased by 12% in 2017 to $50 a barrel. The trade situation involving tariffs on materials including steel and aluminum is also creating uncertainty in the marketplace. Yet construction companies must have materials to complete projects. There is no way around this fact.
How does a hurricane affect construction?
For construction companies, hurricanes can lead to massive destruction of building and facilities. Rebuilding after a storm adds to the supply and demand of materials, further increasing their cost. While material costs increase seasonally in construction, the industry is facing a year-over-year increase, making project profits ever the slimmer.
Why is summer so good for construction?
As the days get sunnier, warmer temperatures create the perfect storm for construction companies. On the one hand, the long days of summer give construction crews more daylight to work with. But an increase in construction projects around the country can equate to a higher demand for materials, which drives up the cost of supplies.
Can you avoid using materials for a project?
Your projects need materials and there might be little you can do to avoid not using these products for your project. That being said, up and coming materials that have yet to gain the popularity of mainstream alternatives might be a wise investment to consider.
How to reduce voltage drop?
1. Increase the Number or Size of Conductors. Parallel or oversized conductors have lower resistance per unit length than the Code-required minimum-sized conductors, reducing voltage drop and increasing energy efficiency with lower losses than using the Code-required minimum-sized conductor. In data centers and other sensitive installations, it is ...
How to limit neutral to ground voltage drop?
To limit neutral-to-ground voltage drop, install a separate, full-sized neutral conductor for each phase conductor in single-phase branch circuit applications.
What is the maximum voltage drop for a branch circuit?
The NEC states in an Informational Note that a maximum voltage drop of 3% for branch circuit conductors, and 5% for feeder and branch circuit conductors together, will provide reasonable efficiency of operation for general use circuits. For sensitive electronic loads, circuits should be designed for a maximum of 1.5% voltage drop for branch circuits at full load, and 2.5% voltage drop for feeder and branch circuits combined at full load.
How does decreasing conductor length affect voltage?
Decreasing conductor length reduces the resistance of the conductor, which reduces voltage drop. Circuit lengths are usually fixed, but some control can be exercised at the design stage if panels or subpanels are located as close as possible to the loads, especially for sensitive electronic equipment.
Why do we need conductor upsizing?
Conductor upsizing is often mandated for the protection of sensitive electronic equipment. Voltage drop can be minimized if the panel or subpanel can be located as close as possible to the point of use. Another measure is to install sufficient circuits to avoid high current levels on any one circuit .