Application of Continuous Hydrologic Modeling to Evaluate and Design Wastewater Land Disposal or Evaporation Systems

摘要

The hydrologic design of land treatment systems has largely been accomplished by annual or semi-annual estimates of the disposition of the input wastewater load. The operation of these systems is, however, dependent upon daily variations in precipitation, evaporation, and land treatment/irrigation area water management. The subject of this report is a hydrologic model which has been developed to design these systems based upon a continuous simulation of the daily water budget of a storage pond and irrigation disposal area system. The user of this program would need to identify a nearby weather station having long-term daily precipitation and temperature records. He would also need to identify the soil type in the disposal area, and specify the storage pond size, the irrigation disposal rate, the crop or cover on the disposal area, and the level of available soil moisture when irrigation ceases. The model monitors the daily pond level fluctuations and overflows; soil moisture, runoff, and percolation in the disposal area; and gives monthly and annual summaries of all hydrologic variables.