An inexpensive, submersible, automatic water sampler

Jonathan B. Martin, Ray G Thomas, Kevin M Hartl

Limnol. Oceanogr. Methods 2:398-405 (2004) | DOI: 10.4319/lom.2004.2.398

ABSTRACT: Currently available water samplers are manually actuated, can only be deployed onshore, limiting their use to small or developed water bodies, or are designed for deployment in the deep sea, making them large and expensive. The automatic submersible water sampler described here is small, lightweight, actuated by a microprocessor, and inexpensively and easily constructed. The sampler consists of a pressure case, sample containers constructed of 10 spring-loaded 60 mL syringes connected to solenoid valves, and electronics to control opening and closing of the solenoid valves. Vacuum in the syringes keeps the springs compressed while the solenoid valves are closed. When a valve opens, the spring expands and draws water past a screen and/or filter into the syringe. Once the syringe is filled, the solenoid valve closes, storing the sample. More than one syringe can be opened simultaneously if more than 60 mL are required. Preservatives can be added to the syringe prior to deployment. Some environments where it could be used include karst aquifers, lakes, large rivers, and estuaries.