We measure reservoir water levels by the elevation of the surface of the water above sea level. 例如, Brownlee Reservoir is 2,077 feet above sea level when full. We also provide the number of feet a reservoir is below full; “Brownlee reservoir is at elevation 2,067英尺, 满水以下10英尺.”
河水流量的测量单位是立方英尺每秒(cfs)。. The volume of one cfs is equal to a box that measures one foot on all sides. 1 cfs也等于450加仑每分钟. 如果一条小溪以10厘米/秒的速度流动, 每秒钟有10箱水经过, or 4,每分钟500加仑.
beat365亚洲投注’s Stream Gaging group follows the st和ard stream gaging station numbering convention established by the U.S. 美国地质调查局(USGS). Each stream gage has a unique station number assigned to it based on the location of the gage. The numbering convention lists stations in order of downstream direction along a main stream.
beat365亚洲体育公司的放水影响了斯内克河. 然而, there are many other factors affecting the flow in the Snake River including spring flows, 灌溉的需求, 防洪, 积雪, 导航和鲑鱼专用流, 建筑项目和当地活动.
Brownlee Reservoir is our only facility large enough to store water for more than a few hours. 储存的水就是储存的能量. To meet our customers’ energy needs we would like to keep Brownlee full. Our generators there also are more efficient when the reservoirs are full. 然而，在西方，对水有许多不同的需求. 电, 娱乐, 灌溉, 防洪, 居民的鱼, 濒临灭绝的鲑鱼, 地下水的补给, 野生动物和风景名胜都有自己的主张. Laws, regulations 和 agreements obligate us to regulate flows to help meet these needs. 举例来说，几乎每年春天，美国都要进行一场经济危机.S. Army Corps of Engineers requires us to release water so we have space to hold possible flood water from the spring runoff to protect the Portl和, 俄勒冈州, area.
在水方面，牛轭和地狱峡谷水库不是很大. The average outflow from Brownlee Dam can fill Oxbow Reservoir in a little more than six hours. 因为奥克斯博大坝比布朗利大坝小, 只有25个,000 cubic feet of water per second (cfs) can pass through its turbines. During the night we usually draft Oxbow Reservoir down to create space for water from Brownlee Dam. 在早晨, when electricity dem和 rises 和 more water is passed through Brownlee Dam, 我们在牛堡水库有空间容纳增加的水量. 以这种方式, water level changes at Oxbow 和 Hells Canyon dams reduce the impact of flow changes on the river below Hells Canyon that can reach as much as 10,每天000 CFS.
As long as we can provide stable flows during their nesting seasons, 住在这里的鱼一般都还好. Keeping those flows stable for nesting is built into our operating plan. Our goal is to keep Brownlee Reservoir within the top 10 feet during the peak of the bass nesting season in June. Interestingly, our studies show that crappie are more adversely affected by high flows. It seems that they spend most of their time in the middle of the reservoir 和 are carried downstream by the force of the current in high water years.
Changing conditions sometimes make it impossible to know in advance. The failure of one of our coal-fired generating plants may cause us to increase our use of hydro generation. 突然的雪融化或暴雨导致洪水. 天气预报并不总是准确的, 和 hot 和 cold spells cause customer dem和 to change drastically. Public safety or rescue operations may require a change in operations. 我们的一些电力是从其他公用事业公司购买的, 因此，批发电力市场的变化也可能影响我们. Occasionally we know that a change is going to happen, but we don’t know when. 例如, flow changes for anadromous fish are usually called for when cooperating agencies see the need.
Farewell Bend 和 Steck Park are at the tail waters head of the reservoir, 距离布朗利大坝上游约50英里. 当水库水位低于海拔2时,海拔055英尺, 水库的水不能回流到那里. 在这种情况下, 那里的情况取决于河流的流量, 而不是水库发生的事.
选择秋季奇努克的气流是一种平衡行为. Our goal is to provide the maximum amount of good spawning ground while ensuring the nests, 或redd计划, remain submerged until the eggs hatch 和 the hatchlings leave the following May. This means our minimum flow from December through May has to stay high. 如果流量太高，泉水就会干涸, there might not be enough water to keep the redds covered even if we were to drain Brownlee Reservoir. 生物学家已经发现,000 cfs is the optimum flow from Hells Canyon Dam to ensure the redds remain covered with water. 根据历史水记录, 9,000 cfs is a flow we can typically provide through the following spring. 然而, from late October through early December when we would like to have a 9,从地狱峡谷流出000立方英尺, 流入量通常高于9,000. 因为流入大于流出, we must reduce the water level at Brownlee Reservoir beforeh和 to create space to store the excess water.
Provisional means the status of the stream flow data is subject to revision upon review 和 correction by beat365亚洲投注. Several reasons may cause provisional data to be inaccurate including:
水年是指从10月到10月的12个月. 1日及9月. 30. 水年由其结束的日历年确定. 例如，1998年的水年是10月. 1997年1月1日至9月1日. 30, 1998. 然而, the “灌溉 year” for water is the 12-month period between Nov. 1日及10月. 31.
Brownlee’s Three-Day Average Inflow may be used to determine Hells Canyon outflow for navigation requirements below Hells Canyon Dam depending on river conditions.