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HomeMy WebLinkAboutStormwater Report - 267 CHICKERING ROAD 11/1/1991 HYDROLOGICAL REPORT PROPOSED "99" RESTAURANT/PUB 267 Chickering Road (Rte 125) North Andover, Massachusetts "99" Restaurant/Pub 160 Olympia Avenue Woburn, Massachusetts 01801 November, 1991 Bernard A. Paquin Project Engineer Dana F.Perkins, inc 125 Main Street Reading, MA 01867 (617) 944-3060 (508) 664-1505 'ZH OF MAssq BERNARD °y A o PAQUIN No. 29763 1 N Bernard A. Paquin Professional Engineer MA Registration #29763 Page 2 CONTENTS Description IPurpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 IIScope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 IIILimitations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 IV General Location and Site Description. . . . . . . . . . 4 V Hydrologic Analysis A. Methodology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Rational Method. . . . . . . . . . . . . . . . . . . . . . . . 5 2 . Soil Conservation Service Method. . . . . . . . 8 3 . Frequency and Probability. . . . . . . . . . . . . . 18 VI Hydraulic Analysis A. Methodology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 1 . Channel/Pipe Capacity. . . . . . . . . . . . . . . . . 19 2 . Runoff Control and Flood Storage. . . . . . 21 VII Design A. Criteria/Techniques/Summary. . . . . . . . . . . . . . . . 23 VIII Sedimentation and Erosion Protection Measures. . 25 IXConclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 XReferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 XIGlossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Figures and Tables Appendix A Existing Runoff Calculations. . . . . . . . . . . . . . . A-1 Appendix B Site Developed Runoff Calculations. . . . . . . . . . B-1 Page 3 I. PURPOSE The purpose of this report is to outline the hydrological and hydraulic aspects and describe the proposed development on the site. This report considers the overall hydrological impacts of the proposed development upon the local watershed with specific emphasis directed toward the adjacent and immediate downstream areas. The hydrologic evaluation is based upon accepted engineering methods and criteria. This study also evaluates interior site and pavement drainage and overall site grading. II. SCOPE The scope of this report is limited to an examination of flooding potentials within the proposed development and an evaluation of existing (pre-development) and proposed (after-development) rates of runoff from the site onto adjacent areas for a two (2) , a ten (10) , and one hundred (100) year storm. The calculations performed in conjunction with this report are based on the existing conditions of the stream channels, drainage systems, and the watershed in terms of land use and storage areas. III. LIMITATIONS The information, plans and calculations contained in this report are intended to be used only by the 1199" Restaurant/Pub, the North Andover Conservation Commission, Planning Board, Engineer, Board of Health and other Town officials as well as the Commonwealth of Massachusetts! Department of Environmental Protection. Written permission by Dana F. Perkins, inc. shall be required prior to the use of any of this material for any other purpose or study. The flood elevations, surface runoff volumes and surface runoff flow rates contained herein should not be considered absolute due to the number of variables involved in their determination (runoff coefficients, runoff curve numbers, times of concentration, rainfall patterns, antecedent moisture conditions, roughness factors, etc) . It should be pointed out that flood elevations and flow rates different from those predicted by this report could occur if: a. Channels and/or culverts within the drainage system become blocked by debris before or during a storm event or if significant Page 4 siltation of drainage structures should occur. b. Significant additional development beyond what is presently proposed (either on-site or off-site) or significant decreases in surface water storage areas (existing and/or proposed) should occur. IV. GENERAL LOCATION AND SITE DESCRIPTION The site and the local watershed of which it is part are located in the southeasterly portion of the Town of North Andover, Massachusetts. The restaurant is located on the easterly side of Chickering Road. The general topography of the site is moderately sloping (zero to three percent (3%) slopes) . The vegetation on the site is a mixture of grasses and weeds. The northeasterly protion of the site contains mixed hardwood and soft wood conifer trees. The soil within the site have been delineated by the U. S.D.A. Soil Conservation Service as being Woodbridge (S.C. S. ) Hydrologic Soils Group "C" , Surface water runoff leaves the site in one location. Figure "A-1" in Appendix A details the drainage area and the point where runoff exits the site. Mean annual rainfall within this general area is 41 + inches and the mean annual runoff is 21 + inches. Major runoff events in this area occur in February and March as the combined result of rainfall and snow melt and in late summer/early autumn from tropical storms. V. HYDROLOGICAL ANALYSIS A. Methodology Although it is recognized as the best possible method of hydrological analysis, obtaining historical data on runoff volumes and peak runoff for individual small watersheds is generally not possible. The U.S. Geological Survey, U. S. Army Corps of Engineers and NOAA National Weather Service have their gauging networks on larger streams and rivers which are considered more important in large scale water resources planning. The U. S. EPA, USDA Soil Conservation Service and the ASCE Urban Water Resources Project have gauged small watershed areas but this information is limited to a few small watersheds across Page 5 the country. obtaining historical runoff data for the particular watersheds involved in this study would not be possible because conditions are constantly changing and many years of data would be required to provide meaningful results. Because of this lack of historical data it is necessary to employ general empirical relationships between watershed parameter known to affect runoff volume and peak rates of runoff. These empirical relationships have been utilized for many years and their coefficients have been refined based on this experience. Although these empirical methods may not be used to predict the runoff from a particular storm event long term experience has shown that if properly applied they are fairly reliable probability models. In this study all flows tributary to the proposed site drainage systems (street drains, site drains) were determined using the Rational Method of Runoff Computation. The hydrographs necessary to determine the overall impact of site development and to design the surface runoff control (detention) areas were determined using the U. S. Department of Agriculture, Soil Conservation Service Method implemented by the use of the Hydro Cad stormwater modeling system. The following is a brief description of the data and techniques used by Dana F. Perkins, inc. to evaluate surface runoff flows for this study. 1. Rational Method The Rational Method, also known as the Lloyd Davies method in the United Kingdom, was first introduced in the United States in 1889. It relates runoff to rainfall intensity by the simplified (rational) formula: Qp=ciA 3 where: Qp = Peak rate of runoff in cubic feet per second (Ft /sec) from the area under consideration. c = Coefficient of runoff, or the ratio of peak runoff to average rainfall intensity (dimensionless number) . i = Average rainfall intensity in inches per hour (in/hr) for the duration and return period under consideration. The storm durations is assumed to be equal to the "time of concentration" for the area. A = Area of watershed (in acres) tributary to the point under consideration. Page 6 The Rational Method is based on the following three assumptions: (1) The peak rate of runoff at any point is a direct function of the average rainfall intensity which occurs during the time of concentration to that point. (2) The frequency of the peak runoff computed by the formula is the same as the frequency of the average rainfall intensity. (3) The time of concentration is the time required for surface runoff to become established and flow from the most remote part of the drainage area to the point under consideration. The latter assumption applies to the most remote area in time, not necessarily distance. Investigations made by W.W. Horner and F.L. Flynt (Ref. #12) based on 20 years of rainfall and runoff records for three urban areas have revealed that although the runoff coefficient varies widely from storm to storm (due to antecedent moisture conditions, time of year, etc. ) and during a storm (due to soil saturation, variable rainfall, etc. ) if rainfall and runoff are considered independent, then a frequency analysis of each has shown the ratio: "c" = park runoff rate for a given frequency average rainfall intensity for a given frequency remains reasonably constant for various frequencies. This fact has been verified by Schakee, et al (Ref. #11) through analysis performed at Johns Hopkins University. Therefore, although a constant value of "c" should not be used to predict the runoff from a specific storm occurrence, it may be used to determine runoff of a particular frequency if the coefficient is applied to the average rainfall intensity having the same frequency. Although the Rational Method involves several assumptions and two difficult-to-determine variables (runoff coefficient "c" and time of concentration "t") , long-time experience has resulted in practical definition of its variables, and its generalized representation of runoff both requires and allows the designer to use his judgment, experience and knowledge of the local area in evaluating the components factors. Thus, the Rational Method has generally been accepted by more than 900 of the engineering offices in the United Page 7 States for use on small drainage areas (less than 1280 acres) . References #9 and #10 give a more complete description of the Rational Method and its component factors. A. Watershed Area The drainage are tributary to any point under consideration in stormwater runoff calculations must be accurately determined. The boundaries of the overall watershed area involved in this study have been established utilizing the site development plans and the U. S. Coast and Geodetic Survey Topographic Maps, South Groveland, MA Quadrangle (Ref #1) . These exterior boundaries of the existing watershed was then verified by a field inspection of the entire area. The drainage area was then divided into sub-areas for the purposes of evaluating the peak runoff tributary to various points in the proposed site drainage system. B. Rainfall Intensity Several factors are involved in the determination of average rainfall intensity, including average frequency of occurrence, local rainfall intensity-duration characteristics for each average frequency of occurrence and the time of concentration. Basic data for rainfall intensity-duration-frequency relationships are derived from actual gauge measurements of rainfall throughout the local area . Statistical procedures are then utilized to produce time- intensity curves for the various frequencies of occurrence. U. S. Weather Bureau, Technical Paper No. 40 (Ref. #6) and NOAA National Weather Service Technical Memorandum No. HYDRO 35 (Ref #7) , upon which all rainfall data utilized herein is based, presents the results of such a statistical analysis for the local area and contiguous United States. The rainfall intensities utilized in this report are based on the analysis for the Town of North Andover/Greater Boston Area. (See Figure # 3) C. Time of Concentration The basic assumption involved in the use of the Rational Method is that the flow, or discharge at a given point, will be greatest when that point is receiving flow from the entire watershed tributary to it. Therefore, it is necessary to establish the time required for a water particle to flow from the portion of the watershed most remote in time (not necessarily distance) to the point under consideration. This time is referred to as the time of concentration and depends on Page 8 the magnitude of ground slope, amount of surface depression storage available, shape of the drainage area, character of the soil and ground cover, antecedent moisture conditions and the length of path of surface flow. One of the major problems involved in the use of the Rational Method is over-estimation of the time of concentration. Since the average rainfall intensity decreases as the time of concentration increases, this leads to under-estimation of the peak runoff value. One method of avoiding this problem is the so-called Rational-Rational Method by which time area isochromes are constructed for each sub-drainage area and incremental runoff calculations are performed for all times less than the longest time. This method is extremely time consuming and tedious. To avoid the problem of over-estimating the time of concentration we have elected to use the "average time of concentration" for each drainage sub-area rather than the longest time. The peak runoff values obtained using average times of concentration are always greater than those obtained using the longest time and therefore considered somewhat more accurate. Concentration times utilized in this study were developed using charts and nomographs contained in Reference #10 and the topographic plans of the proposed development. a. Coefficient of Runoff The runoff coefficient, c, utilized in the Rational Method represents a fixed ratio of average peak rainfall intensity to peak runoff. Obviously this ratio in reality is not a constant value. It is influenced by many differing climatological and seasonal conditions including interception by vegetation, surface depressions, evaporation and transpiration. General engineering practice utilizes average coefficients for various surface and soil types. These average coefficients are assumed not to vary during the storm duration under consideration. In this study composite runoff coefficients have been developed, based on the extent of different soil and ground cover types within each watershed. Soils data for the study was obtained from the U. S. Department of Agriculture Soils Maps for the Town of North Andover, Massachusetts, Soil Survey of Essex County Massachusetts, Northern Part. (Reference #3) 2 . Soil Conservation Service Method The Soil Conservation Service Method for calculating peak rates of runoff and complete runoff hydrogrpahs from urban and suburban areas was first introduced in 1975. This method was a natural outgrowth of many decades of hydrological research in the Soil Conservation Service Page 9 which included actual field measurements and observations of rainfall and runoff from small watersheds throughout the United States. Prior to introducing this method the SCS had developed many (now considered standard) methods for computing peak runoff, hydrograph volumes, unit hydrographs etc. Effective rainfall is considered to be that portion of the actual rainfall which produces direct surface runoff. Losses or abstractions are that portion of the rainfall which does not produce direct surface runoff (detention and retention surface storage, infiltration, evapotranspiration etc. ) . The SCS Method predicts the volume of direct runoff from a watershed using the following series of equations: 2 (P -Ia) Q = (P-Ia ) +S Q= runoff (in) , P= rainfall (in) , S= potential maximum retention after runoff begins (in) , and Ia= initial abstraction (in) . Initial abstraction (Ia) is all losses before runoff begins. It includes water retained in surface depressions, water intercepted by vegetation, evaporation, and infiltration. Ia is highly variable but generally is correlated with soil and cover parameters. Through studies of many small agricultural watersheds, Ia was found to be approximated by the following empirical equation: Ia = 0. 2S. By removing Ia as an independent pararmeter, this approximation allows use of a combination of S and P to produce a unique runoff amount. Using this relationship the basic runoff equation may be rewritten as: 2 Q = (P-0 . 2xS) (P + 0. 8xS) The Soil Conservation Service has developed a system of "Runoff Curve Page 10 Numbers" relating the potential abstraction from rainfall (S) to the soil and cover conditions of a watershed by; 1000 CN = s + 10 from which; S= 1000 -10 CN Numerous tables have been developed by the Soil Conservation Service to determine runoff curve numbers for all combinations and types of soil, cover conditions and antecedent moisture conditions generally encountered (Reference #13) Tables have also been developed by the SCS relating Curve Numbers, total storm rainfall and direct surface runoff volumes (References #13 and #15) . Using the previous runoff equations as well as computer simulation methods the Soil Conservation Service has developed a set of Tabular Unit Hydrographs based on a Type III rainfall distribution. These Unit Hydrographs give various time distributions of runoff on an area of one square mile (640 acres) having a runoff volume of one inch. These Unit Hydrographs are related to the times of concentration for an area and the travel time from that area to the point of interest. To use the method it is necessary to multiply the unit hydrograph ordinants by a ratio of the drainage area times inches of runoff to one square mile inch of runoff. The SCS Method is based on the following assumptions: (1) The total volume of runoff from a watershed is a direct function of the total rainfall and the soil cover complex which exists over that watershed area. (2) The frequency of the runoff volumes and peak rates of runoff computed by the method is the same as the frequency of the rainfall. (3) The hydrograph characteristics of a particular area can be adequately determined by means of the time of concentration, travel time and the total runoff volume. These assumptions are much less limiting than those involved in the Rational Method and more closely describe the actual surface runoff process. The use of the SCS Method for calculating peak runoff over Page 11 many years has lead to a well defined system of runoff curve numbers. Runoff volume and time of concentration determination developed by the SCS have been compared with theoretical and historical information and found to be fairly accurate. Although the SCS Method involves some assumptions and empirical coefficients, it has been found to be a fairly reliable method of calculation for circumstances requiring a knowledge of the time distribution of runoff. The method has been accepted by most federal and state agencies as well as private engineering firms for use on small (less than 200 acres) watersheds. A. Watershed Area The drainage area tributary to the point of interest (runoff control area, point of discharge, etc. ) in the hydrograph calculations must be accurately determine. The boundaries of the existing drainage areas tributary to and located within the site involved in this study have been established utilizing the U. S. Coast and Geodetic Survey Topographic Maps, (Ref #1) and the site topographic survey plan. These boundaries were then verified by a field inspection of the entire watershed. The drainage boundaries for the proposed (developed) site were determined using the previously referenced information regarding the boundaries of drainage areas tributary to the site and an evaluation of the proposed grading and drainage system layout within the site. B. Runoff Curve Number In order to determine the runoff volume, peak rate of runoff and complete runoff hydrograph from a particular drainage area using the SCS Method, it is necessary to evaluate the specific combination of soils, cover and antecedent moisture conditions which exist on the area under consideration. The combinations of soil and cover conditions are called, "Hydrologic Soil Cover Complexes" . The SCS runoff curve number (CN) is a numerical representation of the runoff potential of a watershed. It is the main watershed parameter utilized in calculations and its numerical value depends not only on the hydrologic soil cover complexes but also on the antecedent moisture conditions. When studying watershed hydrology the soil, ground cover and antecedent moisture conditions are considered separately and are brought together when the determination of a runoff curve number (CN) is made. A composite runoff curve number may be computed for a watershed having more than one land use, treatment, ground cover or soil type using a weighted average of the different hydrologic soil cover complexes existing in that watershed. The same antecedent moisture condition is used to calculate runoff from a watershed or Page 12 group of watersheds for a particular storm. However, the antecedent moisture condition, and therefore the curve number, may be varied for the evaluation of different storms. The following is a summary of the general soils, cover and antecedent moisture condition considerations involved in using the SCS Method and the specific data utilized in this study. (1) Soil Types: Since the relative hydrologic response of different soils or soil groups are an essential concern when making runoff determinations, the U. S. Department of Agriculture, Soil Conservation Service has developed a system of classifying the relative surface runoff potentials of various soil types (irrespective of ground cover) . This system is based on extensive studies of soils and runoff throughout the country. The soils are classified into the following "Hydrologic Soils Groups" on the basis of their ability to intake water at the end of long duration storms occurring after prior wetting and the opportunity for swelling without the protective effects of vegetation. SCS HYDROLOGIC SOILS GROUP DESCRIPTION A Soils having high infiltration rates even when (low runoff thoroughly wetted. These soils consist potential) chiefly of deep sands and gravels that are well to excessively drained. These soils have a high rate of water transmission. B Soils having moderate infiltration rates when thoroughly wetted. These soils consist chiefly of moderately deep, moderately well to well drained soils with moderately fine to moderately coarse textures. These soils have a moderate rate of water transmission. C Soils having slow infiltration rates when thoroughly wetted. these soils consist chiefly of moderately fine to fine textured soils with a layer that impedes the downward movement of water. These soils have a slow rate of water transmission. D Soils having very slow infiltration rates when Page 13 (high runoff thoroughly wetted. These soils consist chiefly potential) of clay soils with a high swelling potential, soils with a permanent high water table, soils with a clay pan or clay layer at or near the surface, or shallow soils over nearly impervious materials. These soils have a very slow rate of water transmission. More detailed definitions of depth and soil-drainage classes may be found in Reference #13 . A listing of major soils of the United States classified by hydrologic soil groups may be found in References #13 . Soils data for this study was obtained from the U. S. Department of Agriculture, Soil Conservation Service detailed soil map, Town of North Andover, Essex County, Massachusetts (Reference #3) . The soils data obtained is depicted on Figure #2 of this report. (2) Cover Types : Cover is defined as any material (usually vegetation) covering the soil surface and providing protection from the impact of rainfall. Under ordinary conditions, detailed information about the cover, such as plant density, plant height, root density, root depth, area extent of plant cover and the amount of litter or humus, is seldom available. Even if such detailed information were obtained it must be realized that the data will vary on a year to year, season to season and almost day to day basis. Therefore, it is necessary to rely on generalized land use categories as an index of cover conditions in the hydrologic analysis of watersheds. The SCS method allows for the use of some judgment when choosing the condition for a general cover type thus allowing the engineer to use his experience to better fit local conditions . The type of surface or ground cover on a particular drainage area and its hydrologic condition will affect the rate and volume of runoff from that area. To some degree the initial abstractions from the rainfall (Ia) , the surface depression storage, overland flow depths, times of concentration, (tc) and infiltrations rates (f) all depend on the ground cover type and condition. These variables and their effect on runoff form the watershed are numerically represented by the different curve numbers associated with different cover types. Cover types and condition data for this study were obtained from field observations of the existing watershed and a knowledge of what the proposed development will be. Page 14 (3) Antecedent Moisture Conditions : Antecedent moisture condition refers to the total rainfall for the five day period preceding the design storm. This condition is important when applying the SCS Method as it affects the initial abstractions from the rainfall (Ia) , the maximum potential difference between rainfall and direct runoff volume (S) , and the total runoff volume (Q) . Since the watershed runoff curve number (CN) is a representation of all of these variables, the antecedent moisture condition must be determined to establish the runoff curve number (CN) . The following is a listing of the antecedent moisture conditions utilized by the Soil Conservation Service for performing runoff computations: AMC TYPE DESCRIPTION AMC I A condition of watershed soils where the soils (Dry Con- are dry but not to the wilting point, and when dition) satisfactory plowing or cultivation takes place (lowest runoff potential) . this condition is not generally considered applicable to calculations involving other than common or frequent events. AMC II The average case for annual floods, that is, (Average an average of the conditions that have Condition) preceded the occurrence of the maximum annual flood on numerous watersheds. This condition is generally utilized in most flood runoff and hydrograph calculations involving the design of minor structures. AMC III If heavy rainfall or light rainfall and low (Wet Con- temperatures have occurred during the five dition) days previous to the given storm and the soil is nearly saturated (highest runoff potential) . This condition is generally used only for the most important structures or for the analysis of rare events. The antecedent moisture conditions (AMC) and the corresponding Page 15 rainfall limits for the five day period preceding the design storm are as follows: Antecedent Moisture 5-Day Total Antecedent Rainfall (inches) Condition Class Dormant Season Growing Season I Less than 0. 5 Less than 1. 4 II 0 . 5 to 1. 1 1. 4 to 2 . 1 III More than 1. 1 More than 2 . 1 The runoff curve numbers (CN) utilized for the hydrograph computations for this report are based on AMC II, consistent with normal engineering practice. C. Rainfall: The rainfall data necessary to develop a complete runoff hydrograph from a particular watershed are the total amount of rainfall (rainfall depth in inches) and the storm pattern (the distribution of the rainfall with respect to time) . Rainfall varies geographically, temporarily, and seasonally. The total amount of rainfall depends on the geographic location of the watershed, the storm duration and the average frequency of occurrence of the precipitation. Rainfall intensity, pattern, and the accumulated rainfall mass (as a fraction of the total rainfall mass) will vary within a particular storm event and also from storm to storm. These variations are extremely important when computing runoff hydrographs from urban and suburban areas. Basic data for rainfall depth--duration--frequency relationships are derived from actual gauge measurements of rainfall. The NOAA National Weather Service (successor to the U. S. Weather Bureau) has maintained a network of rainfall gauges throughout the United States since the late 1800 ' s. Statistical procedures are utilized to develop depth-duration relationships from this rainfall data for various (selected) frequencies of occurrence. U.S. Weather Bureau Technical Paper No. 40 (Reference #6) and NOAA National Weather Service technical Memorandum No. Hydro 35 (Reference #7) upon which all rainfall data utilized within this study are based, present the results of such a statistical analysis for the contiguous United States (see Figure #4 for rainfall depth/duration frequency data) . (1) Rainfall Frequency Rainfall frequency or return interval is a measure of how often, on the average, a given total rainfall depth can be expected to Page 16 occur. Although the precipitation amount is also dependent on the storm duration (see below) a particular rainfall and the resulting runoff are referred to as an X-year storm, where X represents the return interval of the rainfall. Rainfall probability may also be expressed as a decimal number between 0 and 1 representing the chance that the rainfall will be equalled or exceeded in any year. For example, a 100 year storm has a 0. 01 or 1 percent chance of being equalled in any year. The rainfall frequency or return period used in the design of drainage facilities such as cross culverts, open channels and drainage detention areas or runoff control areas, is determined according to the potential impact or damage the runoff may have. The frequency of the storm utilized in a particular design will determine the degree of protection provided against flooding and flood damage. The design of all runoff control areas and the evaluation of the impacts of site development on peak runoff from the site are based on a one hundred year storm (T = 100, f=0. 01, R ten year (T = 10, f = 0 . 10) , two year (T = 2 , f=0. 50) R R This criteria is consistent with the recommendations of the U.S. Department of Agriculture Soil Conservation Service, the U.S. . Department of Housing and Urban Development Federal Insurance Administration, the Commonwealth of Massachusetts Department of Environmental Protection, and the Town of North Andover Zoning regulations. (2) Rainfall Duration: The duration of the rainfall as well as the average frequency of occurrence is an important factor in determining the total amount of rainfall . The rainfall duration also affects the volume and peak rates of runoff principally by its effect on the amount of infiltration which can occur during the storm. The SCS Method requires the use of a twenty-four hour duration rainfall event. (3) Rainfall Pattern (Hyetograph) : The rainfall pattern (variation of rainfall intensity with time during a particular storm) and the accumulated rainfall mass curve will vary Page 17 greatly from storm to storm. The U. S.D.A. Soil Conservation Service has analyzed more severe, less frequent storms and have established four standard patterns or rainfall distributions for design purposes. These standard distributions are classified as Type I, IA, II and III. Type I is considered applicable only to southern California while Type IA is considered applicable only to the Pacific Coastal States. All calculations of runoff hydrogrpahs contained herein (using the SCS Method) are based on the Type III rainfall distribution which is applicable to all other areas in the United States. Figure #5 shows the accumulated rainfall mass curve for a Type III, twenty-four hour storm. D. Time of Concentration The time of concentration is the time that it would take for runoff to travel from the hydraulically most distant part of a watershed to the point of interest (point of calculation) . In hydrograph analysis the time of concentration is considered to be the time from the end of excessive rainfall to the point of inflection on the falling limb of the hydrograph. Concentration times are dependent on such watershed parameters as slope, length of travel (watershed shape) , and the type of surface cover (vegetative retardance) . Concentration times are computed by means of equations governing overland and open channel flow or they may be estimated by the use of standard flow velocity charts. In this study the standard SCS overland flow velocity charts (Reference #13) were used to compute times of concentrations. As required by the SCS Method, computed times of concentration were rounded off to match the available unit hydrogrpahs and a minimum of time of concentrations of 0 . 10 hours or 6 minutes was used. 1. Watershed Lag Time In hydrograph analysis lag time is considered the time from the center of mass of rainfall excess (net rainfall after subtractions for infiltration, initial abstractions, evaporation and transpiration, and depression storage) to the peak rate of runoff. Lag time may also be considered as a "weighted" time of concentration. It is related to watershed characteristics such as area, shape, length, slope and flow retardance. Lag time is generally estimated by analyzing rainfall and runoff records for historical events. Based on the studies of many historical rainfall-runoff records for a range of watershed conditions, SCS has developed the following empirical relationship between lag time and time of concentration: L = 0. 6 T Page 18 c This relationship is for average natural conditions for approximately uniform distribution of runoff over the watershed. A further SCS study of urban and suburban runoff hydrographs has shown that this relationship does not vary significantly for urban conditions. Since historical rainfall-runoff data was not available for the watershed under consideration and since this relationship serves as the basis for the SCS Method, it has been utilized for all runoff hydrogrpah computations in this study. (2) Reach Routing Hydrographs calculated in the upper portions of a watershed experience attenuation, reshaping and delay as the water flows downstream through a section of channel or pipe. This attenuation is due to the time it takes for the runoff to travel through the area and in part due to the storage in the channel or pipe. Main channels or tributaries are divided into sections referred to as "reaches" for such routing. The Hydro Cad hydrology program calculates reach routing by use of the storage-indication method. The available outflow is calculated as the cross-sectional area of the channel or pipe at each depth multiplied by the length of the reach. (3) Runoff Volumes and Unit Hydrographs The volume of runoff from the various drainage areas in this study were computed using graphs and tables contained in Reference #13 . These graphs and tables relate total runoff volume (in inches over the watershed) to total rainfall and runoff curve number. Unit hydrographs used for computing the actual runoff hydrographs from the watershed areas were obtained from Reference #13 . These unit hydrographs are given in CFS/Sq Miles/inch of runoff. 3 . Frequency and Probability The design and planning of hydraulic structures is concerned with future events whose time, magnitude and precise conditions cannot be forecast. In order to perform such analysis and design, engineers must resort to statements of probability or frequency with which a specified rate and/or volume of flow will be equalled or exceeded. Storm frequency or design frequency, as utilized herein, is the Page 19 frequency with which a given event is equalled or exceeded, on the average, once in a period of years. Thus, a one hundred year recurrence interval storm would be expected to occur ten times in a one thousand year period. It should not however, be assumed that this storm will occur every one hundred years. During a one thousand year study period, there could be ten one hundred year storms in the first year and none for the remaining nine hundred ninety-nine years. Therefore, it is important to remember the frequencies utilized are long-term average values. Probability, which forms the mathematical basis for prediction, is the reciprocal of frequency. For an exhaustive set of outcomes, probability is the ratio of the outcomes that will produce a given event to the total number of possible outcomes. That is, a one hundred year storm would be expected to occur ten times during a one thousand year period; therefore, the probability of occurrence is one percent. As more commonly stated, there is a one percent chance that runoff expected from a one hundred year storm will be equalled or exceeded in any particular year. VI. HYDRAULIC ANALYSIS A. Methodology The following is a brief description of the methods utilized by Dana F. Perkins, inc. in the hydraulic design of the site drainage system, and the flood routing of the proposed runoff control area. These methods are based upon accepted engineering theory and practice regarding the flow of fluids in conduits and channels. 1. Channel/Pipe Capacity In the conveyance of fluids two types of flow may occur. These are referred to as open channel flow and pressure flow. While the physical makeup of the conduits conveying the fluid may be the same for both types of flow (both may be circular pipes) , the hydraulic function is completely different. Open channel flow is characterized by a free water surface (such as open stream channel or a partially filled pipe (in contrast to pressure flow in which the conduits are always full and under a pressure greater than atmospheric. All street drainage systems proposed for the development were designed for open channel (non-pressure) flow. All hydraulic design calculations of street surface drainage pipes and open channel capacity included herein were based on the Manning Equation for open channel and (non-pressure) pipe flow. The Manning Page 20 Equation is a modification of the original Chezy Equation developed in France in 1769. The Chezy Equation, which can be derived by the use of basic principles of fluid mechanics is: V = C /RS where: V = The average velocity of flow in feet per second (ft/sec) R = The hydraulic radius of the channel or pipe (ratio of the cross sectional area to the wetted perimeter) in feet. S = The slope of the energy grade line (which is equal to the slope of the water surface and channel or pipe bottom for uniform open channel flow) The Chezy coefficient is most frequently expressed as: 1/6 1. 486 R C = n 'Zere: R = The hydraulic Radius (as above) n = The channel (or pipe) roughness coefficient Combining these two equations and multiplying by the channel cross sectional area (A) , results in what is commonly called the Manning Equation: 2/3 1/2 Q = A x 1. 486 x R x S n Q = The channel (or pipe) capacity in cubic feet 3 per second (ft / sec) . A = the channel (or pipe) cross sectional area in 2 square feet (ft ) . n = The channel (or pipe) roughness coefficient R = The hydraulic radius of the channel or pipe (ratio of the cross sectional area (A) to the wetted Page 21 perimeter (wp) S = The slope of the energy grade line (which is equal to the slope of the water surface and channel (or pipe) bottom for uniform flow) . The average velocity of flow (ft/sec) may be obtained by dividing the 3 2 flow rate (ft /sec) by the cross sectional area (ft ) or; V= Q A Solutions to these equations were formulated using charts and graphs contained in References #10 and #17 . Where flow in a pipe occurred at a depth less than full depth the calculations of the flow velocity were based on the hydraulics of the partial cross-section conveying the flow. 2 . Runoff Control and Flood Storage Area Flood Routing Flood routing is the process by which the outflow hydrograph from a flood storage area and water surface elevations within the storage area are derived from the know values of the inflow hydrograph, outflow structure rating curve, storage rating curve, and solutions to the Basic Storage Equation. In reservoirs, ponds and wetlands, the storage capacity and outflow rate are closely related to the water- surface elevation, thus greatly simplifying the procedure. The continuity equation, which is the basis for all form of reservoir flood routing, is concerned with the conservation of mass. For a given time interval, the volume of inflow minus the volume of outflow equals the change in volume of storage, or more simply stated, if what goes into the storage area (inflow) does not flow out (outflow) , it is still there (in storage) . The continuity equation is often written in this simple form: t (I-0) = S where; t = the time interval chosen for the flood routing computations 3 I = the average rate of inflow (ft /sec) during the time interval t 3 0 = the average rate of outflow (ft /sec) Page 22 during the time interval t 3 S = change in volume of storage (ft ) during the time interval t In most applications of the continuity equation, the flow and storage variable are expanded as follows: I =I + I ; 1 2 0=0 +0 S = (S - S ) 1 2 2 1 2 2 So the equation becomes: t (I + I ) - t (0 + 0 ) = S - S ) x2 1 2 1 2 2 1 where: t = (t - t ) = time interval; t is the time at the 2 1 1 beginning of the interval and t is the time at 2 the end of the interval. 3 I = the inflow rate (FT /Sec) at time t ; O = the 1 3 1 2 outflow rate (Ft /Sec) at time t 2 3 0 = the outflow rate (FT /Sec) at time t ;0 = 1 3 1 2 the outflow rate (Ft /Sec) at time t 2 3 S = the storage volume (FT ) at time t S = 1 1 2 3 the storage volume (Ft ) at time t . 2 The average rate of inflow versus time is represented by the inflow hydrograph, the potential rate of outflow is represented by the outlet discharge versus water-surface elevation curve (outflow rating curve) , and the potential storage is represented by the available storage Page 23 versus elevation curve (storage rating curve) . Therefore, in order to actually derive the outflow hydrograph, the water surface elevation/time curve must be derived ( and since the discharge is related strictly to water elevation, this is equivalent to the outflow hydrograph) . Since the continuity equation is not deterministic, that is, the dependent variables cannot be expressed as a direct function of the independent variables, the solution of this equation must be an iterative (trial and error) procedure. Such a solution procedure is included in the HydroCAD computer program. VII. DESIGN A. Criteria/Technique/Summary As existing meadow and wooded areas are developed or modified, a change in the local hydrology will occur. There may be increases in peak runoff rates, decreases in watershed response time and increases in runoff volume. These modifications to the local hydrology are due to the establishment of more efficient and shorter conveyance paths (resulting in decreases in overall time of concentration) and the creation of impervious areas (resulting in decreased infiltration) . The magnitude and effect of these increases in surface runoff should be carefully evaluated. We have investigated the surrounding areas carefully and due to the size and conditions of downstream culverts and channels or topographic conditions, it was our opinion that increases in runoff form the site should be minimized, where possible. In order to minimize the increases in runoff form the site the proposed plans for the development include the construction of a runoff control or "detention" area. This area will serve to slow down, detain and reduce peak runoff from the site by providing a place to store the runoff temporarily. Runoff Control Areas are commonly referred to as "dry" ponds because between periods of rainfall they will not contain water due to the fact that the bottom elevation within the area is the same as the elevation of the outlet pipe, thus allowing the area to drain freely. Appendix "AS' contains the detailed calculations for the existing surface water runoff from the site based on two (2) , ten (10) and one hundred (100) year recurrence interval storms. Figure # A-1 shows the location of the existing drainage area and the point of discharge from the site. Appendix "B" contains the detail calculations of the surface water runoff from the developed (proposed) site for a two (2) , a ten (10) , and one hundred (100) year storm. Figure #B-1 shows the locations of the site developed drainage area Page 24 and the point of discharge from the site. The following is a summary of the impact of site development on the peak rates of surface runoff at the point of discharge from the site. Existing Site Developed Runoff Runoff (2) Year (2 Year) Change Storm (CFS) Storm (CFS) (+/-%) 2 . 3 2 . 4 +4 . 30 Existing Site Developed Runoff Runoff (10) Year (10) Year Change Storm (CFS) Storm (CFS) (+/-%) 4 . 4 3 . 9 -11.4% Existing Site Developed Runoff Runoff (100) Year (100) Year Change Storm (CFS) Storm (CFS) (+/-%) 8 . 3 7. 5 -9 . 6% A review of the above results will indicate that by developing the site as proposed, decreases in runoff for the 10 and 100 year storms will be experienced. The increase shown by the calculations for the 2 year storm is not of concern. Although the percent of increase appears high, the magnitude of the increase (0. 1 CFS) is extremely low and within the round off tolerance of the computer model. VIII SEDIMENTATION AND EROSION PROTECTION MEASURES Page 25 Pollution of surface waters due to sedimentation has become one of the primary environmental concerns when land is developed. Recent studies have shown that severe increase in the amounts of sediments will occur while land is being developed if no control measures are utilized. These increases in sediments are of concern because they may cause damage to fisheries, wildlife, and plant life along a stream, therefore, there is good reason to consider controlling siltation during construction. The control of surface water sedimentation is a two-fold process. The first method is to prevent the erosion and subsequent suspension of soil particles in runoff water. The second method is to remove, or settle, the earth particles once they have become suspended. Since the prevention of erosion is not possible on any active construction site, the following approach will be utilized to control sedimentation from the proposed subdivision. To prevent the sedimentation in surface waters during construction, siltation control fence will be used. The siltation control fence will be placed where shown on the plans and details. These preventive measures will remain in effect until vegetative cover is established on all disturbed areas. In addition to these measures, all catch basins will have a thirty inch minimum sump to trap eroded material both during and after construction. In general, immediately upon completion of surficial grading work, all disturbed areas will be prepared and sown with a suitable quick growing grass cover. IX. CONCLUSION In conclusion, Dana F. Perkins, inc. has considered carefully the hydrological effects of the proposed development on the adjacent and downstream areas. The overall impact of the development upon downstream areas has been minimized by the construction of a runoff control area on the site as outlined herein. Therefore, the effects of the project on FLOOD CONTROL will be minimal. For the same reason the project will have a minimal effect on STORM DAMAGE PREVENTION. Page 26 X. REFERENCES 1. U.S. Department of the Interior, Coast and Geodetic Survey Topographic Maps -- South Groveland, Mass. Quadrangle (1966-Photorevised 1979) 2. Deleted 3. U.S. Department of the Agriculture, Soil Conservation Service, Soil Survey of Essex County Massachusetts, Northern part. 4. Average Annual Runoff and Precipitation in the New England - New York Area, U.S. Department of the Interior Geological Survey. Hydrologic Investigations Atlas HA 7, Washington, D.C. , 1951 5. Recommended Engineering Outlines for the Preparation of Plans and Hydraulic Computations, Commonwealth of Massachusetts Water Resources Commission, Boston, Mass. , February 12, 1975. 6. Rainfall Frequency Atlas of the United States for Durations from 30 Minutes to 24 Hours and Return Periods from 1 to 100 years, D.M. Hershfield, U.S. Weather Bureau Technical Paper No. 40, Washington, D.C. 1961 7. Five to 60 Minutes Precipitation Frequency for the Eastern and Central United States, U.S. Department of Commerce, N.O.A.A. National Weather Service Technical Memorandum #HYDRO-35, Silver Springs, MD, June, 1977. 8. Guidelines for Soil and Water Conservation in Urbanizing Areas of Massachusetts, U.S. Department of Agriculture, Soil Conservation Service, Amherst, Mass. , April, 1975. 9. Design & Construction of Storm and Sanitary Sewers, American Society of Civil Engineers, ASCE Manuals and Reports on Engineering Practice No. 37, New York, NY 1974. 10. Data Book for Civil Engineers--Design--Volume one, Third Edition, Elywn E. Seelye, John Wiley and Sons, Inc. , New York, NY, 1960 11. Experimental Examination of the Rational Method, J.C. Schakee, J.C. Geyer, J.W. Knapp, Journal of the Hydraulics Division, Proceeding of the American Society of Civil Engineers, Paper No. 5607, New York, NY November, 1967. 12. Relation Between Rainfall and Runoff from Small Urban Areas, W.W. Horner and F.L. Flynt, Transactions of the American Society of Civil Engineers, Paper No. 1926, New York, NY, October, 1934. Page 27 13. Urban Hydrology for Small Watersheds, Technical Release No. 55, U.S. Department of Agriculture, Soil Conservation Service, Engineering Division, Washington, D.C. , Second edition June 1986. 14. Design of Small Dams, Second Edition, U.S. Department of the Interior, Bureau of Reclamation, Washington, D.C. , 1974. 15. Introduction to Hydrology, Second Edition, Viessman, Knapp, Lewis and Harbaugh, Harper and Row, New York, NY, 1977. 16. Hydraulic Charts for the Selection of Highway Culverts, U.S. Department of Transportation, Federal Highway Administration, Hydraulic Engineering Circular No. 5, Washington, D.C. , December, 1965. 17. Handbook of Hydraulics for the Solution of Hydrostatic and Fluid-Flow Problems, Fifth Edition, Horace w. King and Ernest F. Brater, McGraw Hill Book Company, New York, NY, 1963. XI. XI. Glossary Acre-foot - An engineering term used to denote a volume I acre in area and 1 foot in depth. (43560 Ft3 or 325,829 U.S. Gallons) alluvial - Pertaining to material that is transported and deposited by running water. Angle of Repose - Angle between the horizontal and the maximum slope that a soil assumes through natural processes. Apron - A floor or lining to protect a surface from erosion, for example, the pavement below chutes, spillways, or at the toes of dams. Aquifer - A Geologic formation or structure that transmits water in sufficient quantity to supply the needs for a water development. The term water-bearing is sometimes used synonymously with aquifer when a stratum furnishes water for a specific use. Aquifers are usually saturated sands, gravel, fractures, cavernous and vesicular rock. Base Flow - The stream discharge from groundwater runoff. Bedding - The process of laying a drain or other conduit in its trench and taping earth around the conduit to form its bed. The manner of bedding may be specified to conform to the earth load and conduit strength. Bedrock - The more or less solid rock in place either on or beneath the surface of the earth. It may be soft or hard and have a smooth or irregular surface. Berms - A shelf that breaks the continuity of a slope. Page 28 Blind Drain - A type of drain consisting of an excavated trench refilled with previous materials, such as coarse sand, gravel or crushed stones, through whose voids water percolates and flows toward an outlet. Often referred to as a French drain because of its initial development and widespread use in France. Borrow Area - A source of earth fill materials used in the construction of embankments or other earth fill structures. Cascades - Section of stream without pools consisting primarily of bedrock, rubble, gravel, or other such material. Current usually more swift than in riffles. Channel - An open cut in the earth's surface, either natural or artificial, that conveys water. Conduit - A closed facility used for the conveyance of water. Contour - 1. : An imaginary line on the surface of the earth connecting points of the same elevation. 2: A line drawn on a map connecting points of the same elevation. Cubic Foot per Second - Rate of fluid at which 1 cubic foot of fluid passes a measuring --int in 1 second. Abbr. cfs. Syn. Second-foot, CUSEC. Cut-and-Fill - Process of earth moving by excavating part of an area and using the excavated material for adjacent embankments of fill areas. Dam- A barrier to confine or raise water for storage or diversion, to create a hydraulic head, to prevent gully erosion, or for retention of soil, rock, or other debris. Design Highwater - The elevation of the water surface as determined by the flow conditions of the design floods. Design Life - The period of time for which a facility is expected to perform its intended function. Diversion - A channel with or without a supporting ridge on the lower side constructed across or at the bottom of a slope for the purpose of intercepting surface runoff. Drainage Area - The land area from which water drains to a given point. Syn. Watershed Area Drawdown - Lowering of the water surface (in open channel flow) , water table, or piezometric surface ( in groundwater flow) resulting from a withdrawal of water. Drop-Inlet Spillway - overfall structure in which the water drops through a vertical riser connected to a discharge conduit. Page 29 Drop Spillway- Overfall structure in which the water drops over a vertical wall onto an apron at a lower elevation. Dry Well - A pit or hole in the ground walled up with unmortared stone, concrete blocks, etc. so as to permit drainage into the ground. Normally dry. Embankment - A man-made deposit of soil, rock, or the other materials used to form an impoundment. Emergency Spillway - A vegetated earth channel used to safely convey flood discharge in excess of the capacity of the principal spillway. Energy Dissipator - A devise used to reduce the energy of flowing water. Erosion - Detachment and movement of soil or rock fragments by water, wind, ice and gravity. Filter Blanket - A layer of sand and/or gravel designed to prevent the movement of fine- grained soils. Filter Strip - A long, narrow vegetative planting used to retard or collect sediment for the protection of diversions, drainage basins, or to other structures. ood Plain - The relatively flat area adjoining the channel of a natural stream which has been, or may be hereafter, covered by flood water. Flood Routing - Determining the changes in the rise and fall of flood water as it proceeds downstream through a valley or a reservoir. Freeboard - The vertical distance between the elevation of the design highwater and the top of the dam, dike, levee, or diversion ridge. Gradient - Change of elevation, velocity, pressure, or other characteristics per unit length; slope. Grading - Any stripping, cutting, filling, stockpiling, or combination thereof which modifies the land surface. Hydrograph - A graph showing for a given point on a stream or drainage system, the discharge, stage velocity, or other property of water with respect to time. Impact Basin - A device used to dissipate the energy of flowing water. Generally constructed of concrete in the form of a depressed and partially submerged vessel and may utilize baffles to dissipate velocities. Land - Any ground, soil or earth including marshes, swamps, drainageways, and areas not permanently covered by water. Page 30 Level Spreaders - A shallow channel excavation at the outlet end of a diversion with a level section for the purpose of diffusing the diversion outflow. Mulching - The application of plant residue or other suitable materials to the land surface to conserve moisture, hold soil in place, aid in establishing plant cover, and minimize temperature fluctuation. Organic Soil - A soil containing at least 20% organic matter, and at least sixteen inches thick, measuring from the ground surface. Muck and peat are organic soils. Outlet - Point of water disposal from a stream, river, lake, tidewater or artificial drain. Peak Discharge - the maximum instantaneous flow from a given storm condition at a specific location. Pool - Section of stream deeper and usually wider than normal with appreciably slower current than immediate upstream or downstream areas, and possessing adequate cover ( sheer depth or physical condition) for protection of fish. Stream bottom usually a mixture of silt and coarse sand. Principal Spillway - Generally constructed of permanent material and designed to regulate *he normal water level, provide flood protection and reduce the frequency of operation of e emergency spillway. Ridge - The bank or dike constructed on the downslope side of a diversion. Riprap - Broken rock, cobbles, or boulders placed on earth surfaces, such as the face of a dam or the channel of a stream, for protection against the action of water. Riser - The inlet portion of a drop inlet spillway that extends vertically from the pipe conduit and controls the water surface elevation. Runoff - That portion of the precipitation that makes its way toward stream channels, lakes or oceans as surface or subsurface flow. When the term "runoff" is used alone, surface runoff usually is implied. Sediment - Solid material, both mineral and organic, that is in suspension, is being transported, or has been moved from its site of origin by air, water, gravity or ice and has come to rest on the earth's surface either above or below sea level. Sediment Basin - A depression formed by the construction of a barrier or dam built at suitable locations to retain rock, sand, gravel, silt or other material. Sheet Flow - Water, usually storm runoff, flowing in a thin layer over the ground surface. Syn. overland flow. Page 31 Side Slopes (engineering) - The slope of the sides of a canal, dam or embankment. It is custormary to name the horizontal distance first, as 1.5 to 1, or frequently 1 1/2:1, meaning a horizontal distance of 1.5 feet to 1 foot vertical. Soil - the unconsolidated mineral and organic material on the immediate surface of the earth that serves as a natural medium for the growth of land plants. Stabilized Center Section - An area in the bottom of a grassed waterway protected by stone, asphalt, concrete or other materials to prevent erosion. Temporary Protection - Stabilization of erosive or sediment-producing areas. Trash Rack - A structural device used to prevent debris from entering a spillway or other hydraulic structure. Vegetative Protection - Stabilization of erosive or sediment producing areas by covering the soil with: a. Permanent seeding, producing long-term vegetative cover, b. Short-term seeding, producing temporary vegetative cover, C. Sodding, producing areas covered with a turf or perennial sod-forming grass. Velocity - The rate or speed of flow measured in feet per second. Watercourse - A natural or constructed channel for the flow of water. FIG. — 1 t Hi 1 F° 190 O 3' -. S hi aop •'�'° aC�o -23< '�`\.�- �1\ • � - 'JCR\� f � O T\ � //, �. 9� � L\l� —_ `! 0 SITE- hem, 6fr� O •.:�)jai I .4i1 over _ y ° A pALE k, cecrl� CD I ranklin - Sch`� LOCUS MAP SCALE 1" = 2083' REFERENCE: USGS TOPOGRAPHIC MAP FIG. -2 L.S.D.A. SOILS MAP SCALE 1" = 1320' . R4�tc i.i`~. ® s J PaB co Ur / 4 + p 'S• ^ a P PaB Sts s Wh Ar- ' � iy. ��ii ` 1 • . � +, Wl$ r-. ` "�f �� •t- ,rte R 4. dA^. ' �R LEGEND WrA = Woodbridge fine sandy loam 0 - 3% slopes FIGURE P3 RAINFALL/INTENSITY/DUP.ATION/FREQUENCY CURVE GREATER-BOSTON, MASS.. ........., c, _ — —— —------ - - - — — t- - - —_ - . — l _ -:---4.- _ .-_-..._- -.�_ .,WE- - ..-. _ z F-7 5 10 15 30 60 DURATION (minutes) - FIGURE RAINFALL/ DEPTH/DURATION/FREQUENCY CURVE GREATER BOSTON, MASS. -- --- - ----- I - - : - - _:.__.::. ,n -- - - - - - _ _ _ ............. ---�- -- -__ _—--- Ip CL I 3 6 12 24 DURATION (hours ) i101 s OOT (sayauz) TTeJuzeg L 9 S £ Z T 0 N O PQ H -- —_ --_ - — ----- --- --- — --- -- - - - - 1 _. tr. Ca O --- wc� a H E { i r t �., x -- 1 .- - G .. j H f H i f.. .• �. . Q, t.. i r- t .. i r .. . �. :-.:�....�._.:�_:.. .. ......t: I.. : . ......... .-- 001 08 09 0+7 OZ 0 TUIOI 30 Z s2 TTUJUTPU APPENDIX A EXISTING RUNOFF CALCULATIONS Data -for 99 RESTAURANT NORTH ANDOVER, MA Pa'_a': 1 Prepared by DANA F. PERKINS, inc . 5 Nov °' Hy d r n C A D Release 2-4 0 (C19 8 6 1.9 9 0 �� 11 e d__M i c r-o g�m p � y sh e m s. ......_. .......-... ......_ ..._ ...._._..... _ .).....__ x._...._ . ' . ..... _ DRAINAGE BASIN FLOW DIAGRAM i i EXISTING i I i ! j j i DEVELOPED LEGEND Subcatchment Area Pond r12] Reach Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems TBCATCHMENT 1 EXISTING RUNOFF 2 Year Storm PERCENT CN 21 .00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 33 .00 79 FAIR OPEN SPACE TYPE III 24-HOUR 46 .00 72 FAIR/GOOD WOODS RAINFALL= 3 . 1 IN 100 . 00 80 PEAK= 2 . 3 CFS @ 12 . 28 HRS AREA= 2 . 40 AC Tc= 22 MIN VOLUME= . 24 AF SUBCATCHMENT 1 EXISTING RUNOFF RUNOFF PEAK= 2 . 3 CFS @ 12. 28 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 .60 . 70 .80 . 90 10. 00 0 .0 0. 0 0 . 0 0. 0 0. 0 0 .0 0 . 0 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 1 . 2 . 2 . 3 . 4 . 6 12 . 00 ; . 9 1 . 6 2 . 2 2. 3 2 .0 1 . 7 1 . 3 1 . 0 . 8 . 6 13 . 00 . 5 . 5 . 4 . 4 . 4 . 3 . 3 . 3 . 3 . 3 14.00 . 3 . 3 . 3 . 3 . 3 . 2 . 2 . 2 . 2 . 2 15 . 00 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 . 2 . 2 16 . 00 . 2 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc . 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems IND 1 existing catch basin STARTING ELEV= 93 . 9 FT FLOOD ELEV= 97 . 0 FT ELEVATION CUM. STOR STOR-IND METHOD (FT) (CF) PEAK ELEVATION= 95 .0 FT 93 . 9 0 PEAK STORAGE = 0 CF 96 . 4 1 Qin = 2 . 3 CFS @ 12 . 28 HRS 96 . 5 5 Qout= 2 . 3 CFS @ 12 . 28 HRS 96. 6 28 ATTEN= 0 % LAG= 0 .0 MIN 96 . 7 79 IN/OUT= . 24 / .24 AF 96 . 8 168 96 . 9 298 97. 0 482 INVERT (FT) OUTLET DEVICES 93 . 9 12" CULVERT n= . 024 L=20' S= . 01 ' 1' Ke= . 2 Cc= . 9 Cd= . 75 TW=1 ' 96 . 5 overflow HEAD(FT) DISCH(CFS ) 0 . 0 0 . 0 . 1 . 3 . 2 1 . 4 . 3 4 . 0 . 4 8 . 5 TOTAL DISCHARGE vs ELEVATION FEET 0 .0 . 1 . 2 . 3 . 4 . 5 . 6 . 7 . 8 . 9 93 . 9 0 . 0 0 . 0 . 1 . 2 . 4 . 6 . 9 1 . 1 1 .4 1 . 7 94 . 9 2 . 0 2 . 3 2 . 5 2 . 6 2 . 7 2 . 9 3 . 1 3 . 3 3 . 5 3 . 6 95 . 9 3 . 8 3 . 9 4 . 1 4. 2 4 . 4 4. 5 4. 6 5 . 1 6 . 3 9 . 0 96 .9 13 . 6 18. 2 POND 1 existing catch basin OUTFLOW PEAK= 2. 3 CFS @ 12 . 28 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 0 . 0 0 .0 0 . 0 0.0 0 . 0 0 . 0 0 . 0 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 1 . 2 . 2 . 3 .4 . 6 12 . 00 . 9 1 . 6 2 . 2 2 . 3 2 . 0 1 . 7 1 . 3 1 .0 .8 . 6 13. 00 . 5 . 5 . 4 .4 . 4 . 3 . 3 .3 . 3 . 3 14 . 00 . 3 . 3 . 3 . 3 . 3 . 2 . 2 .2 . 2 . 2 15 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 16 . 00 . 2 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17 .00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 ; . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems BCATCHMENT 1 EXISTING RUNOFF 10 Year Storm PERCENT CN 21 .00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 33 .00 79 FAIR OPEN SPACE TYPE III 24-HOUR 46 . 00 72 FAIR/GOOD WOODS RAINFALL= 4 . 5 IN 100 . 00 80 PEAK= 4.4 CFS @ 12 . 26 HRS AREA= 2 . 40 AC Tc= 22 MIN VOLUME= . 45 AF SUBCATCHMENT 1 EXISTING RUNOFF RUNOFF PEAK= 4 . 4 CFS @ 12 . 26 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 .70 . 80 .90 10 . 00 . 1 . 1 . 1 . 1 . 1 . 2 . 2 . 2 . 2 . 2 11 . 00 . 2 . 3 . 3 . 3 . 4 . 4 . 5 . 6 . 9 1 . 3 12 . 00 2 .0 3 . 2 4 . 3 4 . 4 3 . 7 3. 0 2 . 4 1 . 8 1 . 4 1 . 1 13 . 00 . 9 . 8 . 7 . 7 . 6 . 6 .6 . 5 . 5 . 5 14 . 00 . 5 . 5 . 4 . 4 . 4 . 4 . 4 . 4 . 4 . 4 15. 00 . 4 . 4 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 16 . 00 . 3 . 3 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 17 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 18 . 00 . 2 . 2 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . l . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS , inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems )ND 1 existing catch basin STARTING ELEV= 93 . 9 FT FLOOD ELEV= 97 . 0 FT ELEVATION CUM.STOR STOR-IND METHOD (FT) (CF) PEAK ELEVATION= 96 . 3 FT 93 . 9 0 PEAK STORAGE = 1 CF 96. 4 1 Qin = 4 .4 CFS @ 12 . 26 HRS 96 . 5 5 Qout= 4. 4 CFS @ 12 . 26 HRS 96 . 6 28 ATTEN= 0 % LAG= 0. 0 MIN 96 . 7 79 IN/OUT= .45 / . 45 AF 96. 8 168 96 . 9 298 97. 0 482 INVERT (FT) OUTLET DEVICES 93 . 9 12" CULVERT n= . 024 L=20' S= .01 ' 1' Ke= . 2 Cc= . 9 Cd= . 75 TW=1' 96 . 5 overflow HEAD(FT) DISCH(CFS ) 0 . 0 0 . 0 . 1 . 3 . 2 1 . 4 . 3 4 . 0 . 4 8 . 5 TOTAL DISCHARGE vs ELEVATION FEET 0. 0 . 1 . 2 . 3 . 4 . 5 . 6 . 7 .8 . 9 93 . 9 0.0 0 . 0 . 1 . 2 . 4 .6 . 9 1 . 1 1 . 4 1 . 7 94 . 9 2 . 0 2 . 3 2 . 5 2 . 6 2 . 7 2 .9 3 . 1 3 . 3 3 . 5 3 .6 95 .9 3 . 8 3 .9 4 . 1 4 . 2 4 . 4 4 . 5 4 . 6 5 . 1 6 . 3 9 .0 96 . 9 13 . 6 18 . 2 POND 1 existing catch basin OUTFLOW PEAK= 4 . 4 CFS @ 12 . 26 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 .60 . 70 . 80 .90 10. 00 . 1 . 1 . 1 . 1 . 1 .2 . 2 . 2 .2 . 2 11 . 00 . 2 . 3 . 3 . 3 . 4 .4 . 5 .6 .9 1 . 3 12. 00 2 .0 3 .2 4. 3 4 .4 3 . 7 3 .0 2 . 4 1 .8 1 . 4 1 . 1 13. 00 .9 .8 . 7 . 7 . 6 .6 .6 . 5 . 5 . 5 14 . 00 . 5 . 5 . 4 . 4 . 4 .4 . 4 . 4 . 4 .4 15. 00 . 4 .4 . 3 . 3 . 3 .3 . 3 . 3 . 3 . 3 16 . 00 . 3 . 3 . 2 . 2 . 2 .2 . 2 . 2 . 2 .2 17 .00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 18.00 . 2 . 2 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 ; . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems -IBCATCER4EW 1 EXISTING RUNOFF- 100 Year Storm PERCENT CN 21 . 00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 33 .00 79 FAIR OPEN SPACE TYPE III 24-HOUR 46 .00 72 FAIR/GOOD WOODS RAINFALL= 7 .0 IN 100 .00 80 PEAK= 8 . 3 CFS @ 12 .25 HRS AREA= 2 . 40 AC Tc= 22 MIN VOLUME= . 85 AF SUBCATCHMENT 1 EXISTING RUNOFF RUNOFF PEAK= 8 . 3 CFS @ 12 . 25 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 .60 . 70 . 80 . 90 10. 00 . 3 . 3 . 3 . 4 . 4 . 4 . 5 . 5 . 5 . 5 11 . 00 .6 . 6 . 7 . 7 . 8 . 9 1 . 1 1 . 3 1 .9 2 . 7 12. 00 4 .0 6 . 2 8 . 2 8 . 2 6 . 9 5 . 5 4 . 3 3 .2 2. 4 2 . 0 13. 00 1 . 7 1 . 4 1 . 3 1 . 2 1 . 1 1 .0 1 . 0 1 .0 . 9 . 9 14. 00 . 8 . 8 . 8 . 8 . 7 . 7 . 7 . 7 . 7 . 6 15 . 00 . 6 . 6 . 6 . 6 . 6 . 5 . 5 . 5 . 5 . 5 16 . 00 . 5 . 4 . 4 . 4 . 4 .4 . 4 .4 . 4 . 4 17 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 18. 00 . 3 . 3 . 3 . 3 . 2 . 2 . 2 .2 . 2 . 2 19 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 20. 00 . 2 Data for 99 RESTAURANT NORTH ANDOVER, NA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems )ND 1 existing catch basin STARTING ELEV= 93 .9 FT FLOOD ELEV= 97 .0 FT ELEVATION CUM.STOR STOR-IND METHOD (FT) (CF) PEAK ELEVATION= 96 . 8 FT 93 . 9 0 PEAK STORAGE = 143 CF 96 . 4 1 Qin = 8. 3 CFS @ 12 . 25 HRS 96 . 5 5 Qout= 8 . 3 CFS @ 12 . 26 HRS 96 . 6 28 ATTEN= 0 % LAG= . 6 MIN 96 . 7 79 IN/OUT= . 85 / . 85 AF 96 . 8 168 96 . 9 298 97 . 0 482 INVERT (FT) OUTLET DEVICES 93 . 9 12" CULVERT n= . 024 L=20' S= . 01 ' 1 ' Ke= . 2 Cc= . 9 Cd= . 75 TW=1 ' 96 . 5 overflow HEAD(FT) DISCH(CFS) 0 . 0 0 . 0 . 1 . 3 . 2 1 . 4 . 3 4 . 0 . 4 8 . 5 TOTAL DISCHARGE vs ELEVATION FEET 0. 0 . 1 . 2 . 3 . 4 . 5 . 6 .7 . 8 . 9 93 . 9 0. 0 0 . 0 . 1 . 2 . 4 .6 . 9 1 . 1 1 . 4 1 . 7 94 .9 2 . 0 2 . 3 2 . 5 2.6 2 . 7 2 .9 3 . 1 3 .3 3 . 5 3 .6 95 .9 3 . 8 3 .9 4 . 1 4. 2 4.4 4 . 5 4. 6 5 . 1 6 . 3 9 . 0 96 .9 13 . 6 18.2 POND 1 existing catch basin OUTFLOW PEAK= 8. 3 CFS @ 12 . 26 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 .60 . 70 .80 .90 10. 00 . 3 . 3 . 3 . 4 .4 . 4 . 5 .5 . 5 . 5 11 .00 . 6 . 6 . 7 . 7 .8 .9 1 . 1 1 .4 1 . 9 2. 7 12 .00 4. 0 5 . 9 8. 1 8. 2 7 . 1 5 . 7 4. 4 3 .0 2 . 6 1 . 8 13 .00 1 .8 1 . 3 1 . 4 1 .0 1 . 2 .9 1 . 1 .8 1 . 1 . 7 14 .00 1 .0 . 7 .9 .6 .9 .6 . 8 .5 . 8 . 5 15 . 00 .8 . 5 . 7 . 4 . 7 . 4 . 7 .4 . 6 . 3 16 . 00 .6 . 3 .6 . 3 . 5 .2 . 5 .2 . 5 . 2 17 . 00 . 5 . 2 . 5 . 2 . 5 . 2 . 4 .2 . 4 . 1 18. 00 . 4 . 1 . 4 : 1 .4 . 1 . 4 . 1 . 4 . 1 19 .00 ; . 4 . 1 . 4 . 1 . 4 . 1 . 4 . 1 . 3 . 1 20. 00 . 3 APPENDIX B DEVELOPED RUNOFF CALCULATIONS Data for 99 RESTAURANT NORTH ANDOVER, 14A Prepared by DANA F. PERKINS, inc. 5 Nov 91 HvdroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems TBCATCHMENT 11 DEVELOPED SITE RUNOFF AREA 1 2 Year Storm PERCENT CN 38 . 00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 10 .00 74 GOOD OPEN SPACE TYPE III 24-HOUR 52 . 00 72 FAIR/GOOD WOODS RAINFALL= 3 . 1 IN 100 .00 82 PEAK= 2 . 4 CFS @ 12 . 11 HRS AREA= 1 .68 AC Tc= 10 MIN VOLUME= . 19 AF SUBCATCHMENT 11 DEVELOPED SITE RUNOFF AREA 1 RUNOFF PEAK= 2 . 4 CFS @ 12 . 11 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 .60 . 70 . 80 . 90 10 . 00 0 . 0 0 . 0 0. 0 0 . 0 0. 0 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 2 . 2 . 2 . 4 . 6 .9 12 . 00 1 . 7 2 . 4 1 . 9 1 . 4 1 . 1 . 8 . 5 . 4 . 4 . 3 13 . 00 . 3 . 3 . 3 . 3 . 2 . 2 . 2 . 2 . 2 .2 14. 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 .2 15 . 00 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, 14A Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems JBCATCE94ENT 12 DEVELOPED RUNOFF AREA 2 PERCENT CN 82 .00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 18 . 00 74 GOOD OPEN SPACE TYPE III 24-HOUR 100 . 00 94 RAINFALL= 3 . 1 IN AREA= . 49 AC Tc= 6 MIN PEAK= 1 . 2 CFS @ 12. 03 HRS VOLUME= .09 AF SUBCATCB14ENT 12 DEVELOPED RUNOFF AREA 2 RUNOFF PEAK= 1 . 2 CFS @ 12 .03 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 .90 10. 00 0.0 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 .00 . 1 . 1 . 1 . 1 . 1 . 1 . 2 . 3 . 4 .6 12 . 00 1 . 2 1 .0 . 6 . 5 .4 . 2 . 2 . 2 . 1 . 1 13 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 14. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 0 . 0 16 . 00 0. 0 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0. 0 0 . 0 0 . 0 0 . 0 17 . 00 0. 0 0. 0 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 0 . 0 18 . 00 0. 0 0 .0 0 . 0 0 .0 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 0. 0 19 . 00 0. 0 0.0 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 20. 00 0. 0 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems JBCATCHMENT 13 DEVELOPED RUNOFF AREA 3 PERCENT CN 76 . 00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 24 . 00 74 GOOD OPEN SPACE TYPE III 24-HOUR 100 .00 92 RAINFALL= 3 . 1 IN AREA= . 35 AC Tc= 6 MIN PEAK= . 8 CFS @ 12 . 03 HRS VOLUME= . 06 AF SUBCATCHNENT 13 DEVELOPED RUNOFF AREA 3 RUNOFF PEAK= . 8 CFS @ 12 . 03 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 .60 . 70 . 80 .90 10 . 00 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0. 0 0. 0 0 . 0 0 . 0 0 .0 11 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 .2 . 3 . 4 12 . 00 . 8 . 7 . 4 . 3 . 2 . 2 . 1 . 1 . 1 . 1 13 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 14 . 00 . 1 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0. 0 0 . 0 0 . 0 0 .0 15 . 00 0 . 0 0. 0 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 0 . 0 0 .0 16 . 00 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0. 0 0 .0 0 . 0 0 .0 17 . 00 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0. 0 0.0 0. 0 0.0 18. 00 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0. 0 0.0 0 .0 0. 0 0 . 0 19 . 00 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 0. 0 0. 0 0 .0 0. 0 0 . 0 20. 00 0 . 0 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc . 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems :ACH 11 DRAIN 1 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS) 12" PIPE STOR-IND METHOD 0 . 0 0 . 0 0 .0 MAX. DEPTH= . 41 FT . 1 0 .0 . 1 n= .011 PEAK VELOCITY= 3 . 3 FPS .2 . 1 . 2 LENGTH= 306 FT CONTACT TIME = 94 SEC . 3 . 2 . 5 SLOPE= . 004 FT/FT Qin = 1 .0 CFS @ 12 .42 HRS . 7 . 6 2 . 2 Qout= 1 .0 CFS @ 12 . 44 HRS . 8 .7 2 .6 ATTEN= 0 % LAG= 1 . 2 MIN . 9 . 7 2 .8 IN/OUT= . 18 / . 18 AF .9 . 8 2 .9 1 .0 . 8 2 . 8 1 .0 . 8 2 . 7 REACH 11 DRAIN 1 OUTFLOW PEAK= 1 . 0 CFS @ 12 . 44 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 .90 10 . 00 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 0. 0 11 . 00 0 . 0 0 . 0 0 . 0 0.0 0 . 0 0. 0 0.0 . 1 . 1 . 2 12 . 00 . 3 . 6 . 9 1 . 0 1 . 0 1 . 0 1 .0 . 9 . 8 . 7 13 . 00 . 7 . 6 . 5 . 5 . 5 . 4 .4 . 4 . 3 . 3 14. 00 . 3 . 3 . 3 . 3 . 2 . 2 .2 . 2 . 2 . 2 15 . 00 . 2 . 2 . 2 .2 . 2 . 2 .2 . 2 . 2 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . l 18 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20 . 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, AAA Prepared by DANA F. PERKINS , inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems :ACH 12 DRAIN 2 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS ) 12" PIPE STOR-IND METHOD 0 . 0 0 .0 0 . 0 MAX. DEPTH= . 41 FT . 1 0 .0 . 1 n= . 011 PEAK VELOCITY= 3. 6 FPS . 2 . 1 . 3 LENGTH= 114 FT CONTACT TIME = 31 SEC . 3 .2 . 6 SLOPE= .005 FT/FT Qin = 1 . 2 CFS @ 12 . 04 HRS . 7 .6 2 . 5 Qout= 1 . 2 CFS @ 12 .05 HRS . 8 . 7 2 . 9 ATTEN= 2 % LAG= . 9 MIN .9 . 7 3 . 2 IN/OUT= . 09 / .09 AF . 9 .8 3 . 2 1 .0 .8 3 . 2 1 . 0 .8 3 . 0 REACH 12 DRAIN 2 OUTFLOW PEAK= 1 . 2 CFS @ 12 . 05 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 .60 . 70 . 80 .90 10 . 00 0 . 0 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 2 . 3 . 4 . 6 12. 00 1 . 1 1 . 1 . 6 . 5 . 4 . 2 . 2 . 2 . 1 . 1 13. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 14.00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 15. 00 . 1 . 1 . 1 . 1 0 .0 0. 0 0. 0 0 . 0 0 . 0 0 . 0 16 . 00 0. 0 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0. 0 0 . 0 0 . 0 0.0 17 . 00 0 . 0 0 . 0 0 . 0 0 .0 0 . 0 0 . 0 0. 0 0 . 0 0. 0 0 .0 18 . 00 0 . 0 0 . 0 0 . 0 0 .0 0 . 0 0. 0 0. 0 0 . 0 0 . 0 0 .0 19 . 00 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0. 0 0. 0 0 . 0 0. 0 0 . 0 20. 00 0 . 0 Data for 99 RESTAURANT NORTH ANDOVER, ILIA Prepared by DANA F. PERKINS , inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems 1ACH 13 DRAIN 3 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS) 12" PIPE STOR-IND METHOD 0 . 0 0.0 0.0 MAX. DEPTH= . 53 FT 1 0 .0 . 1 n= . 011 PEAK VELOCITY= 4.0 FPS : 2 . 1 . 3 LENGTH= 20 FT CONTACT TIME = 5 SEC . 3 . 2 .6 SLOPE= .005 FT/FT Qin = 1 . 7 CFS @ 12. 11 HRS . 7 .6 2 . 5 Qout= 1 . 7 CFS @ 12. 11 HRS .8 . 7 2 . 9 ATTEN= 0 % LAG= 0. 0 MIN .9 . 7 3 . 2 IN/OUT= . 26 / . 26 AF .9 .8 3 . 2 1 .0 .8 3 . 2 1 . 0 . 8 3 . 0 REACH 13 DRAIN 3 OUTFLOW PEAK= 1 . 7 CFS @ 12 . 11 HOURS HOUR 0 . 00 . 10 . 20 . 30 .40 . 50 . 60 . 70 . 80 . 90 10 . 00 0 . 0 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 2 . 2 . 2 . 4 . 5 . 7 12 . 00 1 . 4 1 . 7 1 . 5 1 . 5 1 . 4 1 . 3 1 . 1 1 . 1 1 . 0 . 9 13 . 00 . 8 . 7 . 7 . 6 . 6 . 5 . 5 . 5 . 4 . 4 14. 00 . 4 . 4 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 15 . 00 . 3 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 16 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 1 17. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 ; . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . l 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS , inc . 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems ,ACH 14 EXISTING DRAIN DEPTH END AREA DISCH (FT) (SQ-FT) (CFS) 12" PIPE STOR-IND METHOD 0 .0 0 .0 0 . 0 MAX. DEPTH= . 73 FT . 1 0 .0 0 . 0 n= .024 PEAK VELOCITY= 2 . 8 FPS .2 . 1 . 2 LENGTH= 100 FT CONTACT TIME = 36 SEC . 3 . 2 . 4 SLOPE= . 01 FT/FT Qin = 1 . 7 CFS @ 12 . 11 HRS . 7 . 6 1 .6 Qout= 1 . 7 CFS @ 12 . 12 HRS .8 . 7 1 . 9 ATTEN= 0 % LAG= . 4 MIS .9 . 7 2 . 1 IN/OUT= . 26 / . 26 AF .9 .8 2 . 1 1 .0 . 8 2 . 1 1 .0 . 8 1 . 9 REACH 14 EXISTING DRAIN OUTFLOW PEAK= 1 . 7 CFS @ 12 . 12 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 0 . 0 . l . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 1 . 2 . 2 . 3 . 5 . 7 12. 00 1 . 3 1 . 7 1 . 5 1 . 5 1 . 4 1 . 3 1 . 2 1 . 1 1 .0 . 9 13. 00 . 8 . 7 . 7 . 6 . 6 . 5 . 5 . 5 .4 . 4 14. 00 . 4 . 4 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 15 . 00 . 3 . 2 . 2 . 2 . 2 .2 . 2 .2 . 2 . 2 16 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 1 17 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, 14A Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems AND 11 CATCH BASIN 1 STARTING ELEV= 94 . 7 FT FLOOD ELEV= 98 . 8 FT ELEVATION CUM.STOR STOR-IND METHOD (FT) (CF) PEAK ELEVATION= 95 . 4 FT 94. 7 0 PEAK STORAGE = 2616 CF 95 . 9 4500 Qin = 2 .4 CFS @ 12 . 11 HRS 97. 8 4644 Qout= 1 .0 CFS @ 12 .42 HRS 98 . 0 5073 ATTEN= 58 % LAG= 18 . 7 MIN 98. 2 5950 IN/OUT= . 19 / . 18 AF 98 . 4 7283 98. 6 9158 98. 8 11680 INVERT (FT) OUTLET DEVICES 94. 7 8" ORIFICE Q= . 6 PI r"2 SQR( 2g) SQR(H-r) TOTAL DISCHARGE vs ELEVATION FEET 0 . 0 . 1 . 2 . 3 . 4 . 5 . 6 . 7 .8 . 9 94 . 7 0. 0 0 . 0 . 1 . 3 . 5 . 7 . 9 1. 0 1 . 1 1 . 3 95 . 7 1 . 4 1 . 5 1 . 6 1 . 7 1 . 7 1 .8 1 . 9 2 . 0 2 .0 2 . 1 96 . 7 2 . 2 2 . 2 2 . 3 2 . 4 2 . 4 2 . 5 2 . 5 2. 6 2 . 6 2 . 7 97 . 7 2 . 7 2 . 8 2 . 8 2 . 9 2 . 9 3 .0 3 .0 3 . 1 3 . 1 3 . 2 98 . 7 3 . 2 3 . 3 POND 11 CATCH BASIN 1 OUTFLOW PEAK= 1 . 0 CFS @ 12 . 42 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0 .0 0.0 0.0 0 .0 0. 0 11 . 00 0.0 0. 0 0 . 0 0. 0 0. 0 0.0 0 .0 . 1 . 1 . 2 12 . 00 . 3 . 6 . 9 1 . 0 1 . 0 1 .0 1 .0 .9 .8 . 7 13 . 00 . 7 .6 . 5 . 5 . 4 .4 .4 . 4 . 3 . 3 14 . 00 . 3 . 3 . 3 . 3 . 2 .2 . 2 . 2 . 2 . 2 15 .00 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 . 2 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17.00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, 14A Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems ND 12 CATCH BASIN 2 STARTING ELEV= 97 .0 FT FLOOD ELEV= 97 .8 FT ELEVATION AREA INC.STOR CUM.STOR STOR-IND METHOD (FT) (SF) (CF) (CF) PEAK ELEVATION= 97 . 1 FT 97 . 0 0 0 0 PEAK STORAGE = 14 CF 97 . 2 197 20 20 Qin = 1 . 2 CFS @ 12 .03 HRS 97. 4 789 99 118 Qout= 1 . 2 CFS @ 12 . 04 HRS 97. 6 1776 256 375 ATTEN= 1 % LAG= . 3 MIN 97 . 8 3158 493 868 IN/OUT= .09 / . 09 AF INVERT (FT) OUTLET DEVICES 97 . 0 grate capacity HEAD(FT) DISCH(CFS ) 0.0 0. 0 . 1 . 6 . 2 1 . 8 . 3 3 . 3 . 4 5 . 0 . 5 5 . 8 . 6 6 . 3 TOTAL DISCHARGE vs ELEVATION FEET 0 . 0 . 1 . 2 . 3 . 4 . 5 .6 . 7 .8 . 9 97 .0 0 . 0 .6 1 . 8 3 . 3 5 . 0 5 .8 6 . 3 6 . 8 7 . 3 POND 12 CATCH BASIN 2 OUTFLOW PEAK= 1 . 2 CFS @ 12 . 04 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 .60 . 70 . 80 .90 10 . 00 0. 0 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 2 . 3 .4 . 6 12.00 1 . 2 1 . 1 .6 . 5 . 4 .2 . 2 . 2 . 1 . l 13 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 14 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 0 . 0 0 .0 0 .0 0 . 0 0 . 0 0. 0 16 . 00 0. 0 0 .0 0 .0 0 . 0 0 . 0 0 .0 0.0 0 . 0 0 . 0 0. 0 17 .00 0.0 0. 0 0 .0 0 . 0 0. 0 0 .0 0 .0 0 . 0 0 .0 0. 0 18 . 00 0.0 0.0 0 . 0 0 . 0 0 . 0 0.0 0.0 0. 0 0.0 0. 0 19 . 00 0.0 0 . 0 0. 0 0. 0 0 . 0 0.0 0 .0 0. 0 0 .0 0. 0 20. 00 0 . 0 H Cl) b b O C O O H w z z 0 t) CJ ti > H F- H rT+ z H FJ w N O H O N % W 0o N W O H O rt H N O N O N N d x- (D H C H O (D F-' O O O N H H >' O l0 A 0� l0 N r b (D d �+ N M b N tij N (D w v, o w t-+ °' ° z ro t7i H O r3d > O O H N ci t) ',d G F' �d �J N A O P td cn O rn td H II N 9d N N O Ln N .P O H O O N N f C) FJ 'TJ N N O O) cn W C� nn N Ul N N N N to �4 N N O F" N 0o 0o N O O O O N Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems JBICATCHMENT 11 DEVELOPED SITE RUNOFF AREA 1 Ten Year Storm. PERCENT CN 38 .00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 10 .00 74 GOOD OPEN SPACE TYPE III 24-HOUR 52 . 00 72 FAIR/GOOD WOODS RAINFALL= 4 . 5 IN 100 .00 82 PEAK= 4 . 4 CFS @ 12 . 10 HRS AREA= 1 . 68 AC Tc= 10 MIN VOLUME= . 34 AF SUBCATCHMENT 11 DEVELOPED SITE RUNOFF AREA 1 RUNOFF PEAK= 4 . 4 CFS @ 12 . 10 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 .80 . 90_ 10. 00 . 1 . 1 . 1 . 1 . 1 . 2 .2 . 2 . 2 . 2 11 . 00 . 2 . 2 . 3 . 3 . 4 . 4 . 5 . 8 1 . 2 1 . 8 12 . 00 3 . 1 4 . 4 3 . 3 2 .4 1 . 8 1 . 3 .9 . 7 .6 . 6 13 . 00 . 5 . 5 . 4 . 4 . 4 .4 . 4 . 4 . 4 . 3 14 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 15 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 16 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 1 . 1 17 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20 . 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems JBCATCHMENT 12 DEVELOPED RUNOFF AREA 2 PERCENT CN 82 .00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 18 .00 74 GOOD OPEN SPACE TYPE III 24-HOUR 100 .00 94 RAINFALL= 4. 5 IN AREA= . 49 AC Tc= 6 MIN PEAK= 1 . 8 CFS @ 12 . 03 HRS VOLUME= . 13 AF SUBCATCHMENT 12 DEVELOPED RUNOFF AREA 2 RUNOFF PEAK= 1 . 8 CFS @ 12 . 03 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 2 . 2 . 2 . 2 . 3 . 5 . 7 1 . 0 12 . 00 1 . 8 1 . 6 1 . 0 . 7 . 5 . 3 . 3 . 2 . 2 . 2 13 . 00 . 2 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 14. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 0 . 0 0 . 0 0 . 0 17 . 00 0 . 0 0 . 0 0 . 0 0 . 0 0 .0 0. 0 0 . 0 0. 0 0. 0 0. 0 18 . 00 0. 0 0 . 0 0 . 0 0 . 0 0.0 0. 0 0. 0 0 . 0 0 . 0 0. 0 19 . 00 0. 0 0 . 0 0 . 0 0 . 0 0 .0 0. 0 0. 0 0 . 0 0 . 0 0 . 0 20 . 00 0 . 0 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc . 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems JBCATCHMENT 13 DEVELOPED RUNOFF AREA 3 PERCENT CN 76 .00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 24 .00 74 GOOD OPEN SPACE TYPE III 24-HOUR 100 .00 92 RAINFALL= 4 . 5 IN AREA= . 35 AC Tc= 6 MIN PEAK= 1 .3 CFS @ 12 .03 HRS VOLUME= .09 AF SUBCATCHMSNT 13 DEVELOPED RUNOFF AREA 3 RUNOFF PEAK= 1 . 3 CFS @ 12 . 03 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 .60 . 70 .80 . 90 10. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 1 . 1 . 1 . 2 . 2 . 3 . 5 . 6 12 . 00 1 . 2 1 . 1 . 7 . 5 .4 4 . 2 . 2 . 1 . 1 13 . 00 . 1 . 1 . 1 . 1 14. 00 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 . 1 0 . 0 0 .0 0 . 0 0 . 0 0 .0 16 . 00 0 . 0 0 . 0 0 . 0 0.0 0.0 0 .0 0.0 0.0 0. 0 0 .0 17 .00 0. 0 0 . 0 0 . 0 0.0 0.0 0. 0 0.0 0.0 0. 0 0 .0 18. 00 0.0 0 . 0 0. 0 0 .0 0.0 0 .0 0 .0 0 . 0 0. 0 0 .0 19 . 00 0.0 0 . 0 0 . 0 0 . 0 0 .0 0 .0 0 . 0 0. 0 0. 0 0 . 0 20. 00 0 . 0 Data for 99 RESTAURANT NORTH ANDOVER, HA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems 3ACH 11 DRAIN 1 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS ) 12" PIPE STOR-IND METHOD 0 . 0 0 . 0 0 . 0 MAX. DEPTH= .69 FT . 1 0 . 0 . 1 n= . 011 PEAK VELOCITY= 3 . 8 FPS . 2 . 1 . 2 LENGTH= 306 FT CONTACT TIME = 81 SEC . 3 . 2 . 5 SLOPE= .004 FT/FT Qin = 2.2 CFS @ 12 . 35 HRS . 7 . 6 2 . 2 Qout= 2 . 2 CFS @ 12. 38 HRS .8 . 7 2 .6 ATTEN= 0 % LAG= 1 . 9 MIN . 9 . 7 2. 8 IN/OUT= . 32 / . 32 AF .9 . 8 2 . 9 1 .0 . 8 2 . 8 1 .0 . 8 2 . 7 REACH 11 DRAIN 1 OUTFLOW PEAK= 2 . 2 CFS @ 12 . 38 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 0 . 0 0 . 0 0. 0 0 .0 0 . 0 0. 0 0 .0 0.0 0. 0 0 . 0 11 . 00 . 1 . 1 . 1 . 1 . 1 . 2 . 2 . 2 . 4 . 5 12 . 00 . 8 1 . 2 1 . 4 2 .0 2 . 2 1 . 7 1 . 5 1 . 5 1 . 4 1 . 3 13 . 00 1 . 2 1 . 2 1 . 1 1 .0 . 9 . 9 .8 . 7 . 6 .6 14. 00 . 5 . 5 . 5 .4 . 4 . 4 .4 . 4 . 3 .3 15 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 2 .2 16 . 00 . 2 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 .2 17 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems sACH 12 DRAIN 2 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS) 12" PIPE STOR-IND METHOD 0 .0 0 . 0 0 . 0 MAX. DEPTH= . 53 FT . 1 0 .0 . 1 n= . 011 PEAK VELOCITY= 4 . 0 FPS . 2 . 1 . 3 LENGTH= 114 FT CONTACT TIME = 29 SEC . 3 . 2 . 6 SLOPE= . 005 FT/FT Qin = 1 . 8 CFS @ 12 .03 HRS . 7 . 6 2 . 5 Qout= 1 . 8 CFS @ 12 . 05 HRS . 8 . 7 2 . 9 ATTEN= 2 % LAG= 1 . 0 MIN . 9 . 7 3 . 2 IN/OUT= . 13 / . 13 AF .9 . 8 3 . 2 1 .0 . 8 3. 2 1 . 0 . 8 3 . 0 REACH 12 DRAIN 2 OUTFLOW PEAK= 1 . 8 CFS @ 12 . 05 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 2 . 2 . 2 . 2 . 3 . 5 . 7 . 9 12 . 00 1 . 7 1 . 7 1 . 0 . 7 . 5 . 4 .3 . 2 . 2 . 2 13 . 00 . 2 . 2 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 14. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 0. 0 0 . 0 0 .0 17 . 00 0. 0 0. 0 0 . 0 0. 0 0 .0 0. 0 0 .0 0 .0 0 . 0 0 . 0 18 . 00 0. 0 0. 0 0 . 0 0 . 0 0 .0 0 . 0 0 .0 0. 0 0 . 0 0. 0 19. 00 0 . 0 0 . 0 0 . 0 0 . 0 0 .0 0 . 0 0 .0 0. 0 0 . 0 0 . 0 20. 00 0 . 0 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS , inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems !ACH 13 DRAIN 3 DEPTH END AREA DISCH _(FT) (SQ-FT) (CFS ) 12" PIPE STOR-IND METHOD 0 . 0 0 . 0 0. 0 MAX. DEPTH= . 79 FT . 1 0. 0 . 1 n= . 011 PEAK VELOCITY= 4 . 3 FPS . 2 . 1 . 3 LENGTH= 20 FT CONTACT TIME = 5 SEC . 3 . 2 . 6 SLOPE= .005 FT/FT Qin = 2 .9 CFS @ 12 .09 HRS . 7 . 6 2. 5 Qout= 2 .9 CFS @ 12 . 09 HRS . 8 . 7 2.9 ATTEN= 0 % LAG= . 1 MIN .9 . 7 3 . 2 IN/OUT= . 46 / . 46 AF . 9 . 8 3 . 2 1 . 0 . 8 3. 2 1 . 0 . 8 3 . 0 REACH 13 DRAIN 3 OUTFLOW PEAK= 2 . 9 CFS @ 12 . 09 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 2 . 2 11 . 00 . 2 . 2 . 3 . 3 . 3 . 4 . 5 . 7 1 .0 1 . 5 12 . 00 2 . 5 2 . 9 2 . 4 2 . 7 2 . 7 2 . 1 1 . 7 1 . 7 1 . 6 1 . 5 13 . 00 1 . 4 1 . 3 1 . 2 1 . 1 1 . 1 1 . 0 . 9 . 8 . 8 . 7 14 . 00 . 7 . 6 . 6 . 5 . 5 . 5 . 5 . 5 .4 . 4 15 . 00 . 4 . 4 . 4 . 4 . 4 . 3 . 3 . 3 . 3 . 3 16 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 2 . 2 . 2 . 2 17 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 18 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20 . 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, HA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems iACH 14 EXISTING DRAIN DEPTH END AREA DISCH (FT) (SQ-FT) (CFS ) 12" PIPE STOR-IND METHOD 0 . 0 0 .0 0. 0 MAX. DEPTH= 1 .00 FT . 1 0 . 0 0. 0 n= . 024 PEAK VELOCITY= 2.8 FPS . 2 . 1 . 2 LENGTH= 100 FT CONTACT TIME = 36 SEC . 3 . 2 . 4 SLOPE= . 01 FT/FT Qin = 2 .9 CFS @ 12.09 HRS . 7 . 6 1 .6 Qout= 1 .9 CFS @ 12.00 HRS . 8 . 7 1 . 9 ATTEN= 33 % LAG= 0.0 MIN . 9 . 7 2 . 1 IN/OUT= . 46 / . 46 AF . 9 . 8 2 . 1 1 .0 . 8 2 . 1 1 . 0 . 8 1 .9 REACH 14 EXISTING DRAIN OUTFLOW PEAK= 1 . 9 CFS @ 12 . 00 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 0 . 0 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 2 . 2 11 .00 . 2 . 2 . 3 . 3 . 3 . 4 . 5 . 7 1 .0 1 . 4 12 . 00 1 . 9 1 . 9 1 . 9 1 .9 1 . 9 1 . 9 1 .9 1 . 9 1 .9 1 . 9 13 . 00 1 . 9 1 .9 1 . 9 1 . 9 1 . 1 1 . 0 .9 . 8 .8 . 7 14. 00 . 7 . 6 . 6 . 6 . 5 . 5 . 5 . 5 . 4 . 4 15 . 00 .4 .4 . 4 . 4 .4 . 3 . 3 . 3 .3 . 3 16 . 00 . 3 . 3 . 3 . 3 .3 . 3 . 2 . 2 .2 . 2 17 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 18 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 1 19. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20 . 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS , inc . 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems )ND 11 CATCH BASIN 1 STARTING ELEV= 94 . 7 FT FLOOD ELEV= 98 . 8 FT ELEVATION CUM.STOR STOR-IND METHOD (FT) (CF) PEAK ELEVATION= 96 . 6 FT 94. 7 0 PEAK STORAGE = 4554 CF 95 .9 4500 Qin = 4 . 4 CFS @ 12 . 10 HRS 97. 8 4644 Qout= 2 . 2 CFS @ 12 . 35 HRS 98. 0 5073 ATTEN= 50 % LAG= 14. 7 MIN 98. 2 5950 IN/OUT= . 34 / . 32 AF 98 . 4 7283 98 . 6 9158 98. 8 11680 INVERT (FT) OUTLET DEVICES 94. 7 8" ORIFICE Q= .6 PI r"2 SQR( 2g) SQR(H-r) TOTAL DISCHARGE vs ELEVATION FEET 0 .0 . 1 . 2 . 3 . 4 . 5 .6 . 7 . 8 . 9 94. 7 0 . 0 0 . 0 . 1 . 3 . 5 . 7 . 9 1 . 0 1 . 1 1 . 3 95 . 7 1 . 4 1 . 5 1 . 6 1 . 7 1 . 7 1 . 8 1 .9 2 . 0 2 . 0 2 . 1 96 . 7 2 . 2 2 . 2 2 . 3 2 . 4 2. 4 2 . 5 2 . 5 2 .6 2 . 6 2 . 7 97 . 7 2 . 7 2 . 8 2 . 8 2 . 9 2 .9 3 .0 3 .0 3 . 1 3 . 1 3. 2 98 . 7 3 . 2 3. 3 POND 11 CATCH BASIN 1 OUTFLOW PEAK= 2 . 2 CFS @ 12 .35 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 .80 .90 10. 00 0 . 0 0.0 0 . 0 0 . 0 0. 0 0 .0 0 .0 0 .0 0. 0 . 1 11 . 00 . 1 . 1 . 1 . 1 . 1 . 2 .2 . 3 . 4 . 6 12 . 00 . 9 1 . 2 1 . 5 2 . 1 2 . 1 1 .6 1 . 5 1 . 4 1 . 4 1 . 3 13 . 00 1 . 2 1 . 1 1 . 1 1 . 0 . 9 . 8 .8 . 7 . 6 .6 14. 00 . 5 . 5 . 5 . 4 . 4 . 4 . 4 . 4 . 3 . 3 15 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 2 .2 16 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 17 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 20.00 . 1 Data for 99 RESTAURANT NORTH ANDOVER., MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems )ND 12 CATCH BASIN 2 STARTING ELEV= 97 .0 FT FLOOD ELEV= 97 . 8 FT ELEVATION AREA INC.STOR CUM.STOR STOR-IND METHOD (FT) (SF) (CF) (CF) PEAK ELEVATION= 97. 2 FT 97 . 0 0 0 0 PEAK STORAGE = 19 CF 97 . 2 197 20 20 Qin = 1 . 8 CFS @ 12 . 03 HRS 97 . 4 789 99 118 Qout= 1 . 8 CFS @ 12 .03 HRS 97. 6 1776 256 375 ATTEN= 1 % LAG= . 3 MIN 97 . 8 3158 493 868 IN/OUT= . 13 / . 13 AF INVERT (FT) OUTLET DEVICES 97 . 0 grate capacity HEAD(FT) DISCH(CFS ) 0 . 0 0 . 0 . 1 . 6 . 2 1 . 8 . 3 3 . 3 . 4 5 .0 . 5 5 . 8 . 6 6 . 3 TOTAL DISCHARGE vs ELEVATION FEET 0 . 0 . 1 . 2 . 3 .4 . 5 .6 . 7 .8 . 9 97 . 0 0. 0 . 6 1 . 8 3 . 3 5 .0 5 . 8 6 . 3 6 .8 7 . 3 POND 12 CATCH BASIN 2 OUTFLOW PEAK= 1 . 8 CFS @ 12 . 03 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 . 1 . 1 . 2 . 2 . 2 . 2 . 3 . 5 . 7 .9 12. 00 1 . 8 1 . 6 1 . 0 . 7 . 5 . 4 . 2 . 2 . 2 . 2 13. 00 . 2 . 2 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 14.00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 0.0 0 .0 0 . 0 17. 00 0 .0 0 .0 0. 0 0. 0 0 .0 0.0 0.0 0.0 0 .0 0 . 0 18. 00 0. 0 0. 0 0. 0 0. 0 0 .0 0.0 0.0 0 .0 0.0 0. 0 19. 00 0.0 0. 0 0. 0 0.0 0 .0 0. 0 0.0 0.0 0.0 0. 0 20.00 0. 0 0) M N r-I l0 N ri O O ri r-I CO N r-I O O ri ri H �. N H O O ri Cl1 ri LoJ W U CA 10 Ln N N 0) W U fZ4 N r4 O O r-I 44 r-1 0) O z M aLn 110 d N N II �y N ri O O N W O W O � w rx r-I Ln d o W O N o C� m a w o x >+ Ln Cl) O w w O 'a N N O O Cl) r-I W r 1 ❑ O a N Ln O ("q O • r1 H N ra ri o Cl) O E-1 N r-I N l0 r-I 0) r4 .4 ri N rI M RS r-I +-) O H O 0) 00 N Ol N O ri r 1 Cl) H M H H ' z w x r-I N U H H H � a zz z H O o x o a a U H Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems IBCATCEDURNT 11 DEVELOPED SITE RUNOFF AREA 1 - 100 Year Storm PERCENT CN 38 . 00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 10 . 00 74 GOOD OPEN SPACE TYPE III 24-HOUR 52 .00 72 FAIR/GOOD WOODS RAINFALL= 7 .0 IN 100 . 00 82 PEAK= 8 .0 CFS @ 12 . 10 HRS AREA= 1 .68 AC Tc= 10 MIN VOLUME= .62 AF SUBCATCHMENT 11 DEVELOPED SITE RUNOFF AREA 1 RUNOFF PEAK= 8 . 0 CFS @ 12 . 10 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 .80 . 90 10. 00 . 3 . 3 . 3 . 3 . 3 . 4 .4 . 4 . 4 . 5 11 . 00 . 5 . 5 .6 . 7 . 8 . 9 1 . 1 1 . 7 2 . 5 3 . 4 12 . 00 5 . 9 8.0 5 . 9 4 . 2 3 . 2 2 . 2 1 . 5 1 . 2 1 . 1 1 . 0 13. 00 . 9 . 8 . 8 . 7 . 7 . 7 .7 . 6 . 6 . 6 14 . 00 . 6 . 5 . 5 . 5 . 5 . 5 . 5 . 5 . 4 . 4 15 . 00 . 4 . 4 . 4 . 4 . 4 . 4 . 3 . 3 . 3 . 3 16 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 2 . 2 17. 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 18. 00 . 2 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 . 2 19 . 00 . 2 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 1 . 1 20. 00 . 1 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems 93CATCE94ENT 12 DEVELOPED RUNOFF AREA 2 PERCENT CN 82 . 00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 18 . 00 74 GOOD OPEN SPACE TYPE III 24-HOUR 100 . 00 94 RAINFALL= 7 . 0 IN AREA= .49 AC To= 6 MIN PEAK= 2. 9 CFS @ 12 .03 HRS VOLUME= . 21 AF SUBCATCHMENT 12 DEVELOPED RUNOFF AREA 2 RUNOFF PEAK= 2 . 9 CFS @ 12 .03 HOURS HOUR 0 . 00 . 10 . 20 . 30 .40 . 50 . 60 . 70 . 80 . 90 10. 00 . 1 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 11 . 00 . 2 . 3 . 3 . 3 . 3 . 4 .6 . 8 1 . 1 1 . 5 12 .00 2 .9 2 . 5 1 . 5 1 . 1 . 8 . 5 .4 . 4 . 3 . 3 13 .00 . 3 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 14 . 00 . 2 . 2 . 2 . 2 . 2 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19 . 00 0. 0 0 . 0 0 . 0 0 . 0 0 . 0 0.0 0. 0 0. 0 0 . 0 0 . 0 20 . 00 0 . 0 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc . 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems JBCATCHNENT 13 DEVELOPED RUNOFF AREA 3 PERCENT CN 76 . 00 98 IMPERVIOUS SURFACES SCS TR-20 METHOD 24 .00 74 GOOD OPEN SPACE TYPE III 24-HOUR 100 . 00 92 RAINFALL= 7. 0 IN AREA= . 35 AC Tc= 6 MIN PEAK= 2 . 1 CFS @ 12.03 HRS VOLUME= . 15 AF SUBCATCHMENT 13 DEVELOPED RUNOFF AREA 3 RUNOFF PEAK= 2 . 1 CFS @ 12 .03 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 .90 10. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 11 . 00 .2 . 2 . 2 . 2 . 2 . 3 . 4 .6 .8 1 . 1 12 . 00 2 . 0 1 .8 1 . 1 . 8 . 6 . 4 . 3 . 3 . 2 . 2 13 . 00 . 2 . 2 . 2 . 2 . 2 . 2 . 1 . 1 . 1 . 1 14 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17 . 00 . 1 . 1 0 . 0 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 0 . 0 18 . 00 0 . 0 0. 0 0 . 0 0. 0 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0 . 0 19 . 00 0 . 0 0.0 0 . 0 0 . 0 0 . 0 0. 0 0 . 0 0. 0 0 .0 0 . 0 20 . 00 0 . 0 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 H.ydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems :ACH 11 DRAIN 1 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS) 12" PIPE STOR-IND METHOD 0 . 0 0 . 0 0 . 0 MAX. DEPTH= 1 .00 FT . 1 0 .0 . 1 n= . 011 PEAK VELOCITY= 3 . 9 FPS . 2 . 1 . 2 LENGTH= 306 FT CONTACT TIME = 79 SEC . 3 .2 . 5 SLOPE= . 004 FT/FT Qin = 3 . 1 CFS @ 12 . 41 HRS . 7 . 6 2 . 2 Qout= 2 . 7 CFS @ 12 . 20 HRS .8 . 7 2 .6 ATTEN= 15 % LAG= 0. 0 MIN .9 . 7 2 . 8 IN/OUT= . 60 / . 60 AF .9 . 8 2 . 9 1 .0 .8 2 . 8 1 .0 . 8 2. 7 REACH 11 DRAIN 1 OUTFLOW PEAK= 2 . 7 CFS @ 12 . 20 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 .90 10. 00 0 .0 0. 0 0 . 0 0. 0 0 .0 . 1 . 1 . 1 . 2 . 2 11 . 00 . 2 . 3 . 3 . 4 .4 . 5 . 6 . 7 . 9 1 . 1 12 . 00 1 . 5 2 . 6 2 . 7 2 . 7 2 . 7 2 . 7 2 . 7 2 .7 2 . 7 2 . 7 13. 00 2 . 7 2 . 7 2 . 7 2 . 7 2 . 2 1 . 1 1 . 3 1 . 1 1 . 1 1 . 1 14. 00 1 .0 .9 . 9 .8 . 8 . 7 . 7 .6 . 6 .6 15 . 00 . 6 . 5 . 5 . 5 . 5 . 5 .4 . 4 . 4 .4 16 . 00 . 4 . 4 . 4 . 3 . 3 . 3 . 3 . 3 . 3 . 3 17 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 2 . 2 . 2 . 2 18. 00 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 19 . 00 . 2 . 2 . 2 . 2 .2 . 2 . 2 .2 . 2 . 2 20. 00 .2 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems lACH 12 DRAIN 2 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS) 12" PIPE STOR-IND METHOD 0 . 0 0 . 0 0. 0 MAX. DEPTH= . 77 FT . 1 0 . 0 . 1 n= . 011 PEAK VELOCITY= 4. 3 FPS . 2 . 1 . 3 LENGTH= 114 FT CONTACT TIME = 27 SEC . 3 .2 . 6 SLOPE= . 005 FT/FT Qin = 2 . 8 CFS @ 12. 05 HRS . 7 . 6 2 . 5 Qout= 2. 9 CFS @ 12. 06 HRS .8 . 7 2 .9 ATTEN= 0 % LAG= . 9 MIN .9 . 7 3. 2 IN/OUT= . 21 / . 21 AF .9 . 8 3 . 2 1 .0 . 8 3 . 2 1 .0 . 8 3 . 0 REACH 12 DRAIN 2 OUTFLOW PEAK= 2 . 9 CFS @ 12 . 06 HOURS HOUR 0 . 00 . 10 . 20 . 30 . 40 . 50 .60 . 70 . 80 .90 10. 00 . 1 . 2 . 1 . 2 . 2 . 2 . 2 . 2 . 2 .2 11 . 00 . 2 . 2 . 3 . 3 . 3 . 4 . 5 . 8 1. 1 1 . 5 12 . 00 2 . 6 2 . 8 1 . 6 1 . 1 .9 . 6 . 4 . 3 . 3 .3 13 . 00 . 3 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 14. 00 . 2 . 2 . 2 . 2 .2 . 2 . 1 . 1 . 1 . 1 15. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16. 00 . 1 . 1 . 1 . 1 . l . 1 . 1 . 1 . 1 . 1 17 .00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19. 00 . 1 0 . 0 0. 0 0. 0 0 .0 0.0 0 . 0 0.0 0.0 0.0 20. 00 0 .0 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems 3ACH 13 DRAIN 3 DEPTH END AREA DISCH (FT) (SQ-FT) (CFS ) 12" PIPE STOR-IND METHOD 0 .0 0 . 0 0. 0 MAX. DEPTH= 1 .00 FT . 1 0 . 0 . 1 n= .011 PEAK VELOCITY= 4 . 3 FPS . 2 . 1 . 3 LENGTH= 20 FT CONTACT TIME = 5 SEC . 3 . 2 . 6 SLOPE= .005 FT/FT Qin = 5. 4 CFS @ 12. 10 HRS . 7 .6 2. 5 Qout= 3 . 0 CFS @ 12 . 00 HRS .8 . 7 2. 9 ATTEN= 45 % LAG= 0. 0 MIN .9 . 7 3 . 2 IN/OUT= . 81 / . 81 AF .9 .8 3 . 2 1 .0 .8 3 . 2 1 .0 .8 3 .0 REACH 13 DRAIN 3 OUTFLOW PEAK= 3 . 0 CFS @ 12 .00 HOURS HOUR 0 .00 . 10 . 20 . 30 . 40 . 50 . 60 . 70 . 80 . 90 10 . 00 . 1 . 2 . 2 . 2 . 2 . 3 . 3 . 3 . 4 . 4 11 .00 . 5 . 5 . 6 . 7 . 8 . 9 1 . 1 1 . 5 2 . 0 2 . 6 12 . 00 3 . 0 3 . 0 3 .0 3 . 0 3 .0 3 . 0 3 . 0 3 . 0 3 . 0 3 . 0 13 . 00 3 . 0 3 . 0 3 .0 3 .0 3 .0 3 . 0 3 .0 3 .0 2 . 3 1 . 2 14.00 1 . 2 1 . 1 1 .0 1 .0 . 9 . 9 .8 .8 . 7 . 7 15 .00 . 7 . 7 . 6 .6 . 6 . 6 . 5 . 5 . 5 . 5 16 . 00 . 5 . 5 . 4 . 4 . 4 . 4 . 4 .4 . 4 . 4 17 . 00 ; . 4 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 18 . 00 . 3 . 3 . 3 . 3 . 3 . 3 . 2 . 2 . 2 . 2 19 . 00 ; . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 . 2 20.00 . 2 Data fo.r 99 RESTAURANT NORTH ANDOVER, PRA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems 3ACH 14 EXISTING DRAIN DEPTH END AREA DISCH (FT) (SQ-FT) (CFS) 12" PIPE STOR-IND METHOD 0 . 0 0. 0 0 . 0 MAX. DEPTH= 1 .00 FT . 1 0 .0 0.0 n= .024 PEAK VELOCITY= 2. 8 FPS . 2 . 1 . 2 LENGTH= 100 FT CONTACT TIME = 36 SEC . 3 . 2 . 4 SLOPE= . 01 FT/FT Qin = 3.0 CFS @ 12 . 00 HRS . 7 . 6 1 . 6 Qout= 2. 0 CFS @ 11 . 84 HRS . 8 . 7 1 . 9 ATTEN= 32 % LAG= 0. 0 MIN . 9 . 7 2 . 1 IN/OUT= . 81 / . 81 AF .9 .8 2. 1 1 . 0 . 8 2 . 1 1 .0 . 8 1 . 9 REACH 14 EXISTING DRAIN OUTFLOW PEAK= 2 . 0 CFS @ 11 . 84 HOURS HOUR 0 . 00 . 10 . 20 . 30 .40 . 50 .60 . 70 .80 .90 10 . 00 . 1 . 2 . 2 . 2 . 2 . 2 . 3 . 3 . 4 . 4 11 . 00 . 5 . 5 . 6 . 7 . 8 . 9 1 . 1 1 . 5 2 . 0 1 .9 12. 00 1 . 9 1 . 9 1 . 9 1 .9 1 .9 1 . 9 1 .9 1 .9 1 . 9 1 . 9 13 . 00 1 . 9 1 . 9 1 . 9 1 .9 1 .9 1 . 9 1 .9 1 .9 1 . 9 1 . 9 14. 00 1 . 9 1 . 9 1 . 9 1 . 9 1 .9 1 . 9 1 .9 1 . 9 1 . 9 1 . 9 15 . 00 1 .9 1 . 9 1 . 9 1 . 9 1 . 9 1 . 9 1 .9 . 7 . 4 .6 16. 00 . 4 . 5 . 4 . 4 . 4 . 4 . 4 .4 . 4 .4 17 . 00 . 4 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 18. 00 . 3 . 3 . 3 . 3 . 3 . 3 .2 . 2 . 2 . 2 19 . 00 . 2 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 .2 20. 00 . 2 Data for 99 RESTAURANT NORTH ANDOVER, HA Prepared by DANA F. PERKINS, inc. 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems JND 11 CATCH BASIN 1 STARTING ELEV= 94 . 7 FT FLOOD ELEV= 98.8 FT ELEVATION CUM.STOR STOR-IND METHOD (FT) (CF) PEAK ELEVATION= 98 . 5 FT 94. 7 0 PEAK STORAGE = 8362 CF 95. 9 4500 Qin = 8 .0 CFS @ 12 . 10 HRS 97 . 8 4644 Qout= 3 . 1 CFS @ 12 .41 HRS 98. 0 5073 ATTEN= 61 % LAG= 18. 5 MIN 98. 2 5950 IN/OUT= .62 / .60 AF 98 . 4 7283 98 . 6 9158 98. 8 11680 INVERT (FT) OUTLET DEVICES 94. 7 8" ORIFICE Q=.6 PI r"2 SQR( 2g) SQR(H-r) TOTAL DISCHARGE vs ELEVATION FEET 0.0 . 1 . 2 . 3 . 4 . 5 .6 . 7 .8 . 9 94 . 7 0 . 0 0.0 . 1 . 3 . 5 . 7 .9 1 .0 1 . 1 1 . 3 95 . 7 1 . 4 1 . 5 1 . 6 1 . 7 1 . 7 1 . 8 1 . 9 2. 0 2 .0 2. 1 96 . 7 2 . 2 2 . 2 2 . 3 2 . 4 2 . 4 2 . 5 2 . 5 2 .6 2 .6 2. 7 97 . 7 2 . 7 2 . 8 2 . 8 2 .9 2.9 3 . 0 3 .0 3 . 1 3 . 1 3. 2 98 . 7 3 . 2 3 . 3 POND 11 CATCH BASIN 1 OUTFLOW PEAK= 3 . 1 CFS @ 12 . 41 HOURS HOUR 0 .00 . 10 . 20 . 30 .40 . 50 . 60 . 70 . 80 .90 10 . 00 0. 0 0. 0 0 .0 0 .0 . 1 . 1 . 1 . 1 . 2 . 2 11 . 00 . 3 . 3 . 3 .4 .4 . 5 .6 . 7 1 .0 1 . 2 12 . 00 1 . 5 3 . 0 3 . 1 3 . 1 3 . 1 3 . 1 3 . 1 3 . 1 3 .0 3.0 13 . 00 2 .9 1 . 7 1 . 5 1 . 4 1 . 4 1 . 3 1 .2 1 . 2 1 . 1 1.0 14 .00 1 .0 . 9 .9 .8 .8 . 7 .7 .6 .6 . 6 15 . 00 . 5 . 5 . 5 . 5 . 5 .4 .4 . 4 . 4 . 4 16 . 00 .4 . 4 . 3 . 3 . 3 . 3 . 3 . 3 . 3 . 3 17 . 00 . 3 . 3 . 3 . 3 . 3 . 2 .2 .2 .2 . 2 18.00 . 2 . 2 . 2 .2 .2 . 2 .2 . 2 . 2 . 2 19 . 00 . 2 . 2 . 2 . 2 . 2 .2 . 2 .2 . 2 . 2 20. 00 . 2 Data for 99 RESTAURANT NORTH ANDOVER, MA Prepared by DANA F. PERKINS, inc . 5 Nov 91 HydroCAD Release 2 . 40 (c) 1986 , 1990 Applied Microcomputer Systems 3ND 12 CATCH BASIN 2 STARTING ELEV= 97 .0 FT FLOOD ELEV= 97 .8 FT ELEVATION AREA INC.STOR CUM.STOR STOR-IND METHOD (FT) (SF) (CF) (CF) PEAK ELEVATION= 97 .3 FT 97 .0 0 0 0 PEAK STORAGE = 50 CF 97 . 2 197 20 20 Qin = 2 . 9 CFS @ 12 .03 HRS 97 . 4 789 99 118 Qout= 2 . 8 CFS @ 12 .05 HRS 97 . 6 1776 256 375 ATTEN= 3 % LAG= 1 . 2 MIN 97 . 8 3158 493 868 IN/OUT= . 21 / . 21 AF INVERT (FT) OUTLET DEVICES 97 . 0 grate capacity HEAD(FT) DISCH(CFS) 0.0 0. 0 . 1 . 6 . 2 1 . 8 . 3 3 . 3 . 4 5 . 0 . 5 5 . 8 . 6 6. 3 TOTAL DISCHARGE vs ELEVATION FEET 0 .0 . 1 . 2 . 3 . 4 . 5 .6 . 7 . 8 .9 97 .0 0. 0 . 6 1 . 8 3 . 3 5 . 0 5 .8 6 . 3 6 . 8 7 . 3 FOND 12 CATCH BASIN 2 OUTFLOW PEAK= 2 . 8 CFS @ 12 .05 HOURS HOUR 0 .00 . 10 . 20 . 30 .40 . 50 . 60 . 70 .80 . 90 10. 00 . 1 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 . 2 11 . 00 . 2 . 3 . 3 . 3 . 3 . 4 . 6 . 8 1 . 1 1 . 5 12 .00 2. 7 2 . 7 1 . 5 1 . 2 . 8 . 6 . 4 . 4 . 3 . 3 13. 00 . 3 . 2 . 2 . 2 . 2 . 2 .2 . 2 . 2 . 2 14. 00 . 2 . 2 . 2 . 2 . 2 . 1 . 1 . 1 . 1 . 1 15 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 16 . 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 17 . 00 . 1 . 1 . 1 . 1 . 1 . l . 1 . 1 . 1 . 1 18. 00 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 . 1 19.00 0. 0 0 . 0 0 . 0 0 .0 0.0 0.0 0.0 0.0 0. 0 0.0 20.00 0. 0 Ol O M N In N M O O M r-I OO O M N Ll N M O O M r-I rl l� ri d' M CD N .. N Cl) O O M U] '-i @� w U 00 l0 r-I 'ct' M rZ4 • M U (s+ N M O O O r4 LO ri t� LO � x ri ko o � M o O U) a aa � H m �' N o � r4 o o a >4 O x rI o w Cl) co H N a O > N M r- O r-I w r{ rd O � a N H to H O �i r-I E-4 C4 C4 ll N O P is q r-I o r, W LO N M N 1- !, O E-+ O U1 1, O N is N ri N N 10 ri M r--1 E1 z w rl N U ri H E+ z z CUA H O O �D O P4 a P i I I i I I i i i i i i i I i E t i i I i I I I i i i I