(200) WRi no. 7tf -1<8. ~--~11 AVAILABILITY OF GROUND WATER IN THE BRANCH RIVER BASIN, PROVIDENCE COUNTY, RHODE ISLAND U.S. GEOLOGICAL SURVEY. UP!:o j urc.e.> WATER-RESOURCES INVESTIGATIONS 18-74 ~-/ u_a_L-~·--~= V C) PREPARED IN COOPERATION WITH THE RHODE ISLAND WATER RESOURCES BOARD (._0'- _/ /,A..)((• fv'~J~- AVAILABILITY OF GROUND WATER IN THE BRANCH RIVER BASIN, PROVIDENCE COUNTY, RHODE ISLAND By H. E. Johnston and D. C. Dickerman U.S. GEOLOGICAL Water-Resources Investigations 18-74 Prepared in cooperation with the Rhode Island Water Resources Board December 1974 UNITED STATES DEPARTMENT OF THE INTERIOR Rogers C. B. Morton, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director Open-file report For additional information write to: U.S; Geological Survey Federal Bldg. and U.S.P.O., Room 224 Providence, Rl 02903 CONTENTS Page Abstract---------------------------------------------------------------­ 1 Introduction-----------------------------------------------------------­ 2 Previous studies--------------------------------------------------- 4 Definition of terms------------------------------------------------ 4 Acknowledgments---------------------------------------------------­ 6 Water use--------------------------------------------------------------­ 6 Streamf low- ------------------------------------------------------------- 6 Components of runoff----------------------------------------------­ 7 Effects of geology and topography on runoff------------------------ 12 Aquifers---------------------------------------------------------------­ 12 Bedrock aquifer---------------------------------------------------­ 12 Till aquifer------------------------------------------------------- 13 Stratified-drift aquifer------------------------------------------­ 13 Storage and transmission characteristics---------------------­ 14 Natural recharge and discharge-------------------------------­ 16 Recharge from induced infiltration---------------------------­ 17 Ground-water withdrawals and streamflow depletion------------- 18 Potential sustained yield of selected areas of the strat ified-drift aquifer------------------------------------------~-- 20 Slatersville area-------------------------------------------------­ 23 Oakland area------------------------------------------------------­ 26 Harrisville area--------------------------------------------------­ 28 Chepachet area----------------------------------------------------­ 30 Gazzav ille area---------------------------------------------------- 31 Chemical quality of water----------------------------------------------- 33 Conclusions------------------------------------------------------------­ 37 Selected references----------------------------------------------------- 38 iii ILLUSTRATIONS Page Plate l. Geohydrologic map of the Branch River basin, Rhode Island-----------------------------------------------In pocket Figure l. Map showing location of the Branch River basin---------------- 3 2. Duration curves of daily mean streamflow of the Branch, Chepachet, and Nipmuc Rivers, - 1941-68 water years------------- 8 3. Graph showing recurrence intervals of low f lows of the Branch River at Forestdale, 1941-67 water years--------------- 9 4. t~ap showing low-flow measurements at selected sites in the Branch River basin, August and September 1968------------- 10 5. Hydrographs showing separation of runoff into components of ground-water and surface runoff, average ground-water level, and precipitation-------------------------------------- ll 6. Graph showing relation between duration of pumping and percentage of pumpage being diverted from a source of recharge for selected values of aquifer transmissivity and distance between a well and a recharge boundary----------- 19 7. Map showing areas for which potential sustained yield was evaluated------------------------------------------------- 21 8. Diagram of mathematical model used to evaluate yield of Slatersville area------------------------------------------ 22 9. Sketch showing model aquifer of the Slatersville area--------- 25 10. Sketch showing model aquifer of the Oakland area-------------- 27 ll. Sketch showing model aquifer of the Harrisville a;·ea---------- 29 12. Sketch showing model aquifer of Chepachet area---------------- 32 13. t1ap showing water-quality classes proposed for stream reaches in the Branch River basin by the Rhode Island Department of Health and location of sampling sites for chemical analyses in tables 6 and 7--------------------------- 34 TABLES Page Table l. Transmissivity and average hydraulic conductivity of stratified-drift aquifer estimated from specific- capacity data and lithologic logs----------------------------- 15 2. Summary of data obtained from mathematical model of the Slatersville area at a withdrawal rate of 5.5 mgd------------- 24 3. Summary of data obtained from mathematical model of the Oakland area at a withdrawal rate of 3.4 mgd------------------ 26 4. Summary of data obtained from mathematical model of the Harrisville area at a withdrawal rate of 1.6 mgd-------------- 28 5. Summary of data obtained from mathematical model of the Chepachet area------------------------------------------------ 31 6. Chemical analyses of water from selected wells---------------- 35 7. Chemical analyses of water from selected streams-------------- 36 iv FACTORS FOR CONVERTING ENGLISH UNITS TO INTERNATIONAL SYSTEM {SI) UNITS Multiply English units By To obtain Sl units Length feet (ft) 0.3048 metres (m) miles (mi) 1 .609 kilometres (km) inches (in) 2.54 centimetres (em) Area acres • 00404 7 square k i 1omet res (km 2 ) 2 squaremiles (mi ) 2.590 square k i 1omet res (km 2 ) Volume gallons {gal) 3.785 1 i t res ( 1 ) 3 cubic feet (ft ) .02832 cubic met res {m3 ) Flow feet squared per day (ft2 /day) .0929 metres squared per day (m2 /day) cubic feet per second (ft3 /s) .02832 cubic metres per second (m3 /s) feet per day (ft/day) • 3048 metres per day (m/day) gallons per minute {gpm) .06309 litres per second (1/s) mill ion gal Ions per day (mgd) .04381 cubic metres per second (m3 /s) v AVAILABILITY OF GROUND WATER IN THE BRANCH RIVER BASIN, PROVIDENCE COUNTY, RHODE ISLAND By H. E. Johnston and D. C. Dickerman ABSTRACT Stratified g lacial drift consisting largely of sand and gravel constitutes the only aquifer capable of supporting continuous yields of 100 gpm (6.3 1/s) or more to individual we lls. The aquifer covers about a third of the 79 mi 2 2 (205 km ) study area, occurring main ly in stream valleys that are less than a mi le wide. Its saturated thickness is commonly 40 to 60ft (12 to 18 m); its transmissivity is commonly 5,000 to 8,000 ft 2 /day (460 to 740m2 /day). The aquifer is hydraulically connected to streams that cross it and much of the water from heavily pumped wells wi ll consist of infiltration induced from them. Potential sus tained yield from most parts of the aquifer is 1 imited chiefly by the rate at which infiltration can be induced from streams or low streamflow, whichever is smaller. Ground-water withdrawa ls deplete streamflow; and if large-scale development of ground water is not carefully planned and managed , periods of no streamflow may result during dry weather. Potential sustained yield varies with the scheme of well development, and is evaluated for selected areas by mathematically simulating pumping from assumed schemes of we! Is in models of the stream-aquifer system. Results indicate that sustained yields of 5.5, 3.4, 1.6, and 1.3 mgd (0.24, 0.15, 0.07, and 0.06 m3 /s) can be obtained from the stratified-drift aquifer near Slatersville, Oakland, Harrisville, and Chepachet, respectively. Pumping at these rates wil 1 not cause streams to go dry, if the water is returned to streams near points of withdrawal. A larger ground-water yield can be obtained, if periods of no streamflow along reaches of principal streams are acceptable. Inorganic chemical quality of water in the stream-aquifer system is suitable for most purposes; the water is soft, slightly acidic, and generally contains less than 100 mi lligrams per litre of dissolved sol ids. Continued good quality ground water depends on maintenance of good quality of water in streams, because much of the water pumped from we! Is wil 1 be infiltrated from streams. -1- INTRODUCTION This report deals with ground-water resources of the part of the Branch River basin in northwestern Rhode Island upstream from the U.S. Geological Survey gaging station at Forestdale, Rl, an area of 79 mi 2 or 205 km2 (fig. 1). It is one of a series prepared in cooperation with the Rhode Island Water Resources Board to provide quantitative information on the availability of large supplies of ground water in Rhode Island. The area is a thinly populated section where either surface-water or ground-water resources are available to meet long-term needs of public-supply systems. The area has several ponds, lakes, reservoirs, and a moderate amount of swampy area; it is drained by several perennial streams. Reservoirs that impound the principal streams originally were constructed to supply water for power generation, processing, and waste disposal for textile mills, but are used now largely for recreation. Two additional reservoirs have been proposed: one on Tarkiln Brook in the eastern part of the basin would provide 5.4 mgd (0.24 m3 /s); the other on Nipmuc River in the northern part of the basin would provide 9.0 mgd or 0.39 m3 /s (Metcalf and Eddy, 1967). Most of the water would augment public­ supply systems in northern Rhode Island. Neither site is in an area where large