LOCATION.-- Lat 41°58'27", long 87°42'22" (NAD of 1927), in NW1/4SW1/4 sec.12, T.40 N., R.13 E., Cook County, Hydrologic Unit 07120003, on right downstream side of bridge in West River Park in Chicago, 0.1 mi upstream from North Shore Channel, and at mile 43.4.

DRAINAGE AREA.-- 113 mi².

PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE

DISCHARGE: October 1989 to September 1998; June 2000 to current year.

STAGE: October 1994 to September 1998, June 2000 to current year.

GAGE.-- Water-stage recorder and phone telemeter. Datum of gage is 580.67 ft above NGVD of 1929.

EXTREMES FOR PERIOD OF RECORD.--

SURFACE-WATER DISCHARGE AND STAGE: Maximum discharge, 2,360 ft³/s, Feb. 21, 1997, gage height 6.81 ft; minimum discharge, 3.6 ft³/s, Aug. 5,6, 1993.

Table of Contents

Introduction

Station Descriptions

Surface-Water Data

Ground-Water Data

Meteorological Data

Biological Data