Water shortage is becoming more and more serious in North China，and the influence of urban water crisis is becoming more and more extensive． This paper analyzes the key factor of water shortage in northern cities，and offers the strategies to solve the water shortage problem in North China based on the sustainable use of water resources． The strategy includes rational allocation of local surface water， groundwater，reclaimed water，rainwater，water transfer，and pass-by water resources to improve the urban water supply guarantee rate． A large water network is built to achieve groundwater recharge balance and to ensure the joint dispatch of external water and local water，surface and ground water，conventional and emergency water sources． We select Langfang City as a typical area，a city short of water． We follow the basic principle of water supply-demand balance“water-saving first，water transfer second，water pollution control first，water supply second，environmental protection first，water use second”to balance the supply and demand of water resources by an analysis of“three balances”．Based on the results of water balance analysis in typical areas，the average annual water shortage in Langfang in 2030 will be 0．02 billion m3 ( water consumption will be 1．363 billion m3，water supply will be 1．361 billion m3) ，and the water deficit will be 0．1%． This paper supplied the principle of water allocation and the scheme of green water network interconnection for water-lacking cities in North China．

As the city ＇s drainage system and the regional drainage system，both design and design standards for the duration of the difference，which would cause pipeline drainage and river drainage works does not converge． Based on the rainfall data from 1981 to 2015 in Shuyang County，the Copula function is used to establish a joint distribution probability model for the maximum 2-hour short-duration pipeline drainage storm and the maximum 1-day long-duration drainage of the corresponding time period after a suitable marginal distribution function is selected through precision analysis． The coexisting recurrence period of short duration during heavy rain exceeding a certain design value and the long duration during heavy rain exceeding a design value calculated． At present，the results can provide a scientific basis for the construction of urban drainage and waterlogging prevention system，and ensure the safety of urban drainage and waterlogging prevention．

Considering that the calculation of urban rainwater utilization potential and benefit identification are the first step in urban rainwater utilization，the commonly used methods of urban rainwater utilization potential calculation and its benefit identification are studied in this paper． After that，an improved model of urban rainwater utilization potential based on water balance and the coupling function identification model of function and demand are established in this paper． Based on the data of rainfall and statistical yearbook from 1956 to 2015 in a city built area in Yunnan Province，the above two models are used to calculate the average annual rainwater utilization potential of 537．29 million cubic meters and the benefit factor of rainwater resource utilization potential in 2020 include industrial water demand，urban water supply，ecological water demand and supplementary groundwater． The results show that the improved model of urban rainwater utilization potential based on water balance is effective and the factors are comprehensive and the physical process is clear and the results are closer to reality． Because the function and demand coupling benefit identification model can avoid duplication or omission of benefit identification，the benefit factor recognition is more accurate．

SWAT model is one of the main tools to solve the problem of hydrological simulation and environmental assessment. Taking Huluhe basin as the study area, the monthly scale SWAT model from 2006 to 2012 was established to explore the response of the runoff, sediment and nutrient in different sub-watersheds, and determine the sub-watershed delineation. Based on the reasonable sub-watershed delineation level to simulate monthly runoff and verify its applicability. The results showed: (1) With the increase of the number of sub-watersheds, the runoff, sediment and nutrient showed a significant increase and then decreased, and finally became stable. Huluhe basin reasonable sub-watershed delineation level was 37. (2) Based on the runoff simulation of 37 sub-watersheds, Nash-Sutcliffe coefficients (Ens) in calibration and validation period were 0.84 and 0.81 respectively, and the coefficients of determination(R2) were 0.76 and 0.62 respectively, and the simulation results were satisfactory. The result can provide an effective reference for further hydrological simulation in Huluhe basin.

In this page, we obtain depth of soil water runoff by investigating different runoff components. The functional relationship between the depth of soil water runoff and the parameters of runoff components can be establish with free water reservoir in hillslope hydrology. Finally, taking the Chenhe catchment in Shanxi province as a typical basin. The results of applications in Chenhe catchment shows that this method is effective. Compared to traditional method, the method in this paper can estimate the parameters in water source partition rapidly and accurately. It can reduce the numbers of parameters which should be confirmed. And it may reduce the chance of equifinality for different parameters.

Hydrological forecasting in the lack of data is one of the key and hot issues in the field of hydrology. At present, one of the conventional methods of hydrological forecasting at home and abroad was regionalization method. This paper summarized the research progress of hydrological forecasting in the lack of information area through combing the literatures, and discussed the applicability of regionalization method, the existing problems and the uncertainty. Finally, it put forward some problems and breakthroughs that need to be solved urgently in the future research.

Interaction between vegetation cover pattern and soil and water loss is a hotspot in hydrology and soil erosion research. Quantifying vegetation cover pattern can indicate the soil and water loss potential under a vegetation cover pattern. Indicators incorporating soil and water loss mechanism are effective in handling this issue. In this study, the efficiency of leakiness index (LI) developed based on plot and hillslope experiments was tested at the watershed scale. The results revealed an exponential relationship between LI and sediment delivery. It indicates the validity of LI in reflecting the impact of vegetation cover pattern on sediment delivery. However, the LI lost the effectiveness in linking vegetation cover pattern with runoff. It is concluded that LI is capable to indicate the effect of vegetation cover pattern on sediment delivery, and additionally, to be a powerful tool for evaluation vegetation pattern planning for soil loss control.

Being suffered rainstorm and waterlogging is a common problem for China’s cities in the process of economic development, especially in Guangzhou. Prevention and control of flooding is an important measure in residential area, which is the most basic function unit of city. A typical residential area in Guangzhou was selected as the study object to generalize the drainage system by using SWMM. The flow and the drainage system was simulated in the design storms of different return periods. The rain flood between the area pre- and post-development was compared, and the preventive effect of on modeled three LID technologies was discussed. Results showed that, watershed peak and runoff coefficient increased significantly, and the time of max occurrence became earlier after post-development, sunken lawn, permeable pavement and roof rainwater collection system could effectively reduce peak flows and runoff efficient, and could be effective in relieving the pressure of could increase the amount of rainwater resource utilization.

Taking the Qianhu campus of Nanchang University as an example, the swmm model was used to simulate the water quality.The parameters of the model are confirmed by using the measured rainfall data.It is proved that the model can simulate the characteristics of non - point source pollution of rainfall runoff in this area.On the basis of this, the swmm model was used to design the meteorological conditions such as different reproduction period, rain peak coefficient and early drought days, so as to analyze the concentration of TSS, CODcr, TN and TP in rainwater runoff with rainfall transformation.The results show that: (1) With the increase of the reproduction period, the peak value of the pollutant concentration becomes larger and the peak appears in advance; (2) With the increase of the rain peak coefficient, the peak concentration of the pollutant becomes larger and the peak time is delayed;(3) The number of days before the drought will only affect the peak concentration of pollutants and pre-concentration growth trend, there is no impact on the peak time.

In order to remove low concentration Pb(Ⅱ) in water by rice husk ash(RHA), RHA before and after adsorption was analyzed by Fourier transform infrared spectroscopy (FTIR), the adsorption characteristics of low concentration Pb(Ⅱ) from water were investigated by static adsorption. The results showed that there were multiple groups on the RHA surface, and some polar groups participated in Pb(Ⅱ) adsorption; the adsorption capacity increased with increasing the solution pH; at the initial concentration of 20.0 mg/L and temperature was 25℃, the best dose of RHA was 1.8 g/L and the removal rate of Pb(Ⅱ) was 98.1%; Na(Ⅰ) and Ca(Ⅱ) in solution could hinder the adsorption of Pb(Ⅱ), and the effect of Ca(Ⅱ) was more obvious than Na(Ⅰ). The analysis showed that the adsorption isotherms at different temperatures were fitted better to Freundlich equation, which indicated polymolecular layer adsorption, increasing temperature was favorable for adsorption. ΔG?<0, ΔH?>0 and ΔS?>0 indicated that the adsorption was a spontaneous, entropy increasing and endothermic process. The kinetic experimental data of the adsorption fitted better to the pseudo-second-order equation, the adsorption was maybe controlled by surface adsorption and intraparticle diffusion.

The quantifications of trans-regional eco-compensation in Minjiang River Basin from 2011 to 2015 were estimated by the standard calculation method based on water environmental capacity. The results indicated that the most upstream districts were acceptors of eco-compensation. The eco-compensation amount in Longyan, Ningde and Quanzhou cities were 2045.82~3023.91×104 Yuan, 3037.71~4009.84×104 Yuan, and 6205.73~6605.81×104 Yuan, respectively. The mid-stream city Sanming, and Nanping needed to pay for the eco-compensation to the upstream areas, but also received the eco-compensation in the lower reaches. The eco-compensation amount in Sanming and Nanping cities (payout and reception) were -2476.78~1967.35×104 Yuan and -5062.21~4091.23×104 Yuan, respectively. The downstream city Fuzhou needed to pay 10426.13~16148.56×104 Yuan for eco-compensation. The Minjiang River Basin eco-compensation mechanism which should including water pollution control mode, eco-compensation model, and eco-compensation fund raising were also discussed in this article.

Water samples of water environment and hydroecology factorS were collected in April，July，October，January from 2013 to 2015 to explore water environmental carrying capacity condition of Tenggeli Lake in Zhongwei． The factors of ammonia nitrogen ( NH3 －N) ，total nitrogen( TN) ，total phosphorus( TP) ，permanganate index ( CODMn ) ，chemical oxygen demand( CODCr ) ，phytoplankton ShannonWiener index，zooplankton Shannon-Wiener index，zoobenthos Shannon-Wiener index and comprehensive nutrition status index were selected as evaluating indicators，and the method of Artificial Neural Network Model was used to analyze WECC in Tenggeli Lake． The results show that water environmental carrying capacity of Tenggeli Lake were 0． 69，0． 63 and 0． 46 from 2013 to 2015，and the water environmental carrying capacity of Tenggeli Lake was in a state of basic bearing capacity．

Irrigation can affect the production and emission of CO2 by affecting the life activities of the microorganisms in soils and the root growth of crops. In order to reveal the emission characteristics of CO2 of soils in summer maize under deficit irrigation, the experiment was carried out by using the method of static chamber/gas chromatography in situ observation of soil CO2 emission from summer maize under the transform of farmland moisture proving ground of China academy of the water-saving agriculture in arid of Northwest A & F University in June-October, 2015. Three treatments were contained in the experiment: sufficient irrigation (CK), deficit 20% of water (T1), deficit 40% of water (T2).The results showed that: The CO2 flux of soil in summer maize field reached the peak after sowing and dropped to a low level until it reached a short sub-peak after irrigation and then remained at a low level until corn harvested. The CO2 emission flux of soil was CK> T1> T2 after irrigation, and there was significant difference between CK and T2, T1 and T2 (P <0.05). Exponential positive correlations between CO2 fluxes and soil water-filled pore space (WFPS) were observed in summer maize under different irrigation levels and the correlation was significant (P<0.01).The results suggested that deficit irrigation inhibited CO2 emissions from soil in some extent , the CO2 emission flux was maintained at a low level when the soil water-filled pore space was less than 50%, but when the soil water-filled pore space was higher than 50%, the CO2 emission flux increases greatly with the increase of water-filled pore space. The study results can provide a reference of water conservation and reduction of greenhouse gas emissions in farmland.

With the increasing pollution of drinking water in villages and towns, it is urgent to use water quality sensors to monitor water quality in villages and towns online. According to protection starting late, the budget less, the geographical distribution dispersed, and monitoring not in time for drinking water source of villages, a set of relatively complete drinking water quality online monitoring system was designed in this paper. Water quality testing technology, GPRS technology and network communication technology was adopted to achieve real-time remote Web monitoring and live camera features in the system. Then scene photo could be real-time transferred to phones. The system has the advantages of low price, flexible operation and accurate measurement, self-cleaning, and environmental resilience, so it can be popularized and used in various fields of water quality monitoring.

In recent years, as an important means of supporting implementation of the most stringent water resources management, water intake monitoring system construction has been received increasing attention. For problems of stability, reliability, practicability and efficiency during system construction and running，by summarizing the experiences of the construction and operation and maintenance of many water monitoring systems, the paper puts forward 7 technologies，such as upgrading of RTU（Remote Terminal Unit），the optimization strategy of the measurement scheme，metering and integration methods in complex conditions, metering data integration technology for multi-brand meters, Data anomaly diagnosis based on logical chain, R&D of water resources monitoring system and exploration of operation and maintenance management mode, to increase stability and reliability of the system. It provides important technical supporting and reference for perfecting and effective of water intake monitoring system.

Joint operation of reservoirs as non-engineering measures plays an important role in current urban flood control. However, with the increasing in the number of reservoirs and the limitations of the mathematical model and optimization techniques (such as "dimension disaster" problem in the dynamic programming), an optimal operational rules of the reservoirs becomes more and more difficult to be obtained. In order to develop a joint operational rule for the urban flood control within the planning stage of reservoirs, forward and inverse analysis methods are proposed based on the flood discharge capacity in the control reach of a city river. A case study was conducted in the flood control of Duyun city for the joint operation of reservoirs within the planning process. The rationality and operability of the proposed methods have been verified in the case study. Results indicate that the reverse analysis method can reduce the uncertainty of the reservoir operation plan better than the forward analysis method. In addition, the results can also be used as a reference for similar urban flood control planning.

The effects of rockfill deformation control of the high CFRD is the core point, Mainly because of the rock fill creep deformation’s existent, the later phase deformation will be growing by time, which may cause much safety hidden trouble for the anti-seepage structure such as face and toe board. The back-analysis method provides an effective way to confirm rheological parameters of the dam, Based on deformation observation data of CFRD. More rheological parameters are used to define the indexes of higher settlement sensitivity, select out 7 rheological parameters for back analysis, which saves computation space. Inspired by the natural selection of natural species, the method combining the genetic algorithm with finite element analysis is used to screen parameters, parameters are filtered by copying, crossing, and mutating, remain which is highly similar with the actual monitoring data, in this way we get optimal rheological parameters. The proposed method is adopted to evaluate the rheological parameters of Shuibuya concrete face rockfill dam. It is shown that the calculated settlements of the inversion parameters agree generally well with the measurements with regard to both magnitude and trend, showing that the proposed method is applicable. Using the rheological parameters got from back analysis for long-term deformation of dam, predict that the deformation of dam will be in reasonable range by 2020.

In order to analyze the running characteristics of axial flow pump in saddle zone，the internal flow field of the axial flow pump with ns = 822 is simulated and analyzed. The external performance was tested by experiment. The results show that the difference of head simulation value and experimental value is less than 1%, the difference of efficiency simulation and experiment value is within 2 percentage points. Under the condition of 0.6QBEP，the static pressure distribution of blade pressure surface is not uniform. The pressure gradient of static pressure from impeller inlet to outlet gradually increases. Low pressure appears on the suction surface. Under the condition of 0.55QBEP, the static pressure from blade inlet to outlet gradually increases. Under the optimal conditions, the vorticity helix Hn distribution on blade pressure surface and suction surface is uniform. There is a significant vortex concentrated area in the suction surface and pressure surface. The impeller inlet near the front edge in the saddle area appears back flow and the impeller outlet close to the hub has clear vortexes. The research results can provide a reference for the optimization of the unstable operation characteristics of axial flow pump.

In order to study the pressure pulsation in the super low head tubular pump of different head and different blade angle, with a new pumping station, using the method of physical model experiment, the impeller inlet and the guide vane outlet arrangement of two pressure measuring points, the pressure pulsation in super low head tubular pump is studied through time domain analysis and frequency domain analysis. The results show that the super low head tubular pump’s maximum pressure pulsation occurs between the impeller and the guide vane; at the inlet of the impeller, the pressure pulsation is stronger than larger head when the head is smaller; at the guide vane outlet, the pressure pulsation is stronger than smaller head when the head is larger; it can be seen from the cavitation phenomenon that the blade setting angle has a great influence on the pressure pulsation; the main frequencies of pressure pulsation at impeller inlet and guide vane outlet were both blade passing frequency (BPF); in the condition of large head, the low-frequency pressure pulsation whose frequency between 1 to 2 times of rotation frequency is significantly larger, this phenomenon was not found in the low head conditions.

Combined with the present situation and existing problems of the construction of drainage pumping station automation in the Pearl River Delta, this paper puts forward the standards of perfecting the drainage pumping station automation construction, strengthens the ways of transformation and upgrading the single station, enhances the intellectuality and the group control of the drainage pumping station, reduces the operating cost of the pumping station, establishes the ideas and the directions of the transformation of the emergency mechanism. The author discuss the practical application of automation construction of pumping station and the ways of realizing the integration of management and control, water conservancy informatization and video technology application. The conclusion can be used for the study of automatic upgrading and transformation of pumping station in Pearl River Delta area.

Based on the multi-stage centrifugal pumps with a high head，high rotational speed，high reliability and so on，the rotor of the pump is studied through rotor dynamics design． The vibration modal of the entire rotor is analyzed by numerical calculation． After that，5 natural frequencies and the corresponding vibration model diagram can be obtained． Then the corresponding“dry”critical rotational speeds are calculated through the natural frequency of the pump． The“wet”critical rotational speeds are calculated by making an analysis of the pre-stressed model with fluid-solid interaction method． The result is that“wet”critical rotational speed is less than“dry”critical rotational speed in the same order． The first order“wet”critical rotational speed of the rotor is 5074r/min，which is much larger than the actual speed 2980 r/min． The results show that the design of the pump rotor consistent with the structural dynamic design requirements．

Power mechanical components such as impellers vibrate more easily under external excitation or self power． To avoid harmful consequences such as fatigue damage and structural damage，it is important to analyze its vibration characteristics deeply． In this paper，the impeller of XA100 /32 single stage centrifugal pump in a dry state is taken as the object of study，organically combining ANSYS Workbench collaborative simulation platform，the Germany BBM vibration test and analysis system and the LMS Test．lab experimental modal analysis software． The first six natural frequencies and vibration modes of the impeller are obtained by simulation and modal analysis respectively． The relative error of the inherent frequency of the two methods is basically less than 10%．

According to the control effect of conventional PID is difficult to achieve the desired and single neural network on-line setting problems of complex structure, long training time, slow convergence speed, this paper proposes a BP neural network PID control based on principal component optimization. In this scenario, the analysis of the network input layer element analysis dimensionality reduction using principal components, in order to simplify the structure of the network, improve the network convergence speed and generalization ability, and enhance the quality control of intelligent control system. Based on the above theory, the simulation analysis of turbine governing system is carried out on the MATLAB/Simulink platform,and analysis of the test results shows that BP neural network PID control based on principal component analysis control effect than before optimization has been significantly improved.

Due to the small space inside the large mechanical cooling tower, the fans driven by turbine should maximize to reduce the size and improve the efficiency. In this paper, a special type of spiral case with full elliptical cross section was designed, and water flowed out axially from the bottom .This design greatly reduced the radial size of the turbine. Combined with the design theory of the traditional spiral case, the hydraulic design method of the full elliptical spiral case under steady state was deduced. Through the instance design and analysis of numerical simulation, it could verify that the flow data of the special spiral case was consistent with the theoretical value of design conditions, and the hydraulic loss was only 1.05%, the whole turbine efficiency was up to 88.25%, the performance was stable. The turbine designed in this paper can be directly installed in the cooling tower because of its compact structure, so it has a broad application prospect for the energy saving of the existing electric fan cooling tower.