Abstract A new clean biopolymer-based fracturing fluid has been developed. The new fluid has high conductivity, stable viscosity, low pipe friction, excellent proppant transport, and the capability to be used with produced water. This fluid-system development effort was aided by the evolution of a new approach to proppant transport measurement as well as the operational deployment of a dry-polymer blender used to effectively hydrate the fluid system as part of an on-the-fly treatment. The new fluid has been field-trialed in 14 frac stages over four wells with about two million pounds of proppant placed. The application of the new fluid and experience of the field-trials are discussed. This new clean fluid is widely applicable to fracturing low-permeability reservoirs worldwide and can be used where both waterfrac and traditional gelled fluids are currently used. This fluid signals a dramatic shift in fracturing low-permeability unconventional reservoirs by coupling excellent proppant transport with high conductivity. Introduction Traditional guar-based fracturing fluids, as commonly used, give poor retained fracture conductivity. This has been shown in several studies in which the effective fracture length is a fraction of the modeled propped fracture length as shown by production history matching (Peles et al. 2002). Other types of fracturing fluids that have high retained fracture conductivity in tests can be cost prohibitive and often have poor proppant transport, for example, surfactant gels and water fracs, respectively. Another common issue is that the water must be fairly fresh for the fluid chemistry to work properly. A feasibility project was initiated to develop a fracturing fluid that would address the limitations of traditional guar systems. The design objectives of this feasibility project were to produce a fracturing fluid that would:○Provide good proppant conductivity (> 75% at 6,000 psi with 2 lb/ft2 30/50 ISP).○Have sufficient viscosity to created good fracture width (initial viscosity > 200 cP).○Provide good proppant transport○Have good fluid-loss characteristics○Provide a good viscosity break○Have stable viscosity at BHT of approximately 200°F○Be a simple system to operationally execute○Be within current economic bounds○Stay within current HSE guidelines Constant communications between R&D and the field were imperative to the dynamic nature of this technology development—at the outset, the target was to deliver a usable system to the field in less than one year. Weekly reviews were implemented to review lab results and guide the project along to expedite this timeline. (Development of a new fracturing fluid, as opposed to an improvement on an existing, can typically take years). The development team that was established for this project kept the end in sight and was able to produce a viable product, ready for field trial, in less than eight months. Several approaches were examined but were eventually dropped because of technical, operational, or economic considerations. It was concluded that an advanced biopolymer-based, linear-gel fluid system could meet all of the design objectives. Additionally, the new fluid system could provide viable viscosity without being crosslinked—consequently the fluid could be readily formulated with produced water. Since this feasibility project was completed, the applicable temperature range and conditions have been expanded and this fluid system is now a commercial product.