Learn & Explore/Habitats/Streams/Survey Data

Survey Data

DAR gathers survey data from streams and waterways to monitor and protect freshwater ecosystems.

Freshwater Survey Data Overview

The Division of Aquatic Resources (DAR) collects multiple types of data to monitor and protect Hawai‘i’s freshwater ecosystems. These surveys include:

  • Biological monitoring using the point quadrat count method, drift sampling, and larval trapping
  • Additional scientific surveys (e.g., insects, algae) conducted by DAR or partner institutions
  • Data use: monitoring, assessing, managing, and protecting freshwater aquatic resources across the State

Point Quadrat Count Method includes

  • Surveying stream biota
  • Recording native and introduced species of: Fish, Crustaceans, Mollusks, Insects, Algae
  • Documenting environmental conditions: Habitat type, Substrate type, Survey area, Temperature, Elevation
d3beaa1cf49053ee7d6d286ddc0e703c62b4b5ba

DAR Freshwater Database Overview

The Division of Aquatic Resources (DAR) Freshwater Database contains survey data for Hawai‘i’s freshwater systems, including: perennial and intermittent streams, reservoirs, lakes, ponds, ditches, and diversions.

Key Points About the Database

  • Historical data: Records date back to the early 1960s.
  • Hawai‘i  Stream Assessment (HSA): Developed in 1990 as a cooperative project involving:
    • Commission on Water Resource Management
    • Department of Land and Natural Resources
    • National Park Service Cooperative Park Studies Unit, University of Hawai‘i
    • National Park Service Rivers, Trails, and Conservation Assistance Program
  • Data search: Streams or water bodies can be located using an address, HSA code, or DAR code.

DAR Stream Coding System

DAR has its own 8-digit numeric coding system to track streams and tributaries. This system is based on the 7-digit HSA code with an extra digit added to incorporate intermittent streams and drainage basins.

DAR Code Breakdown (8 digits, 00000000)

1. First digit : Island

  • 2 = Kauai
  • 3 = Oahu
  • 4 = Molokai
  • 6 = Maui
  • 8 = Hawai‘i
 
45f088c6e302d12f48dbba470f358f8c2b808427

2. Second digit: Hydrographic Unit (HGU)

  • Regional drainage areas established in the 1970s by USGS and DOWALD

3. Third–fifth digits: Stream identifier

  • Expanded to 3 digits to include intermittent streams and drainage basins
  • Coding continues sequentially around the island

4. Sixth–eighth digits: Tributary segment identifier

  • Note: Knowing the island and HGU is necessary to locate a specific stream or tributary.
1a41e323f6b627ecfd1f905f2a139d8587e84842 (1)

Searching the Database

  • First-order streams (no tributaries): Search by stream name.
  • Streams with tributaries: Must know the tributary name.
  • Filtering in MS Access:
    • Highlight the correct HSA_code or DAR_code field
    • Use the funnel function to filter out irrelevant data

Reference for stream names: United States Department of Interior, Geological Survey; Topographic Quadrangle Maps, 7.5-minute series, 1983.